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The Ultimate 3D Print Quality Troubleshooting Guide 2018

You’re here because you’ve either just had a complete 3D print failure, or your prints aren’t quite perfect. We don’t settle for less than perfect, so we don’t expect you to either. Rest assured the problems and solutions to every 3D printing issue you could experience are explained in this tips & fixes-packed guide to 3D printing.


Each issue has a clear high resolution photograph, a detailed explanation of the subject and a problem solving checklist for how to improve 3D print quality. This includes instructions for software settings and even best practices for specific prints and materials, where applicable.


To use the guide, you can view the expandable contents list, and click on the problem you’re experiencing to jump to that section. Hover over or the thumbnails to view a supersize image if you’re not sure of the issue you’re looking for. If you can’t see the issue from the content thumbnails, just take your time and scan through the guide to find the section you wish to read up on. We hope you’ll find this guide invaluable!

First Layer Issues
The first layer of your print is prob...
Print Not Sticking To The Bed
This is one of the most common issues...
Prints Sticking Too Much
Maybe less common than the opposite p...
Warping

Warping occurs when the physical f...

Inconsistent Extrusion: How To Fix Under Extrusion

3D printing under extrusion is one...

Extruding Wrong Amount Of Plastic

In previous chapter, we looked at ...

Filament Not Feeding Properly

Proper operation depends on your e...

Extruder Is Grinding Filament

The picture on the left shows a se...

Extruder Is Crushing Filament

This piece of filament in the pict...

Other Filament Issues
The quality and state of your filamen...
Clogged Nozzle
Clogged extruders happen. Here are wh...
Other Blockages

Unfortunately, the nozzle isn’t th...

Stringing and Oozing
3D Printer Stringing and nozzle oozin...
Overheating

The tip of this (supposed) spike g...

Elephants Foot

Classic problem in 3D printing. We...

Walls Caving In

In this picture, we’re looking at ...

Curling and Rough Corners

This beams corners in the picture ...

Cracking or Layer Separation

Cracking occurs when 3D printing l...

Layers Shifting & Misaligned Layers
Some 3D printing issues appear as com...
Layers Missing or Skipped Layers

Most likely the layer isn’t missin...

Weak or Under-Extruded Infill

Your 3D printing infill looks weak...

Deformed Infill
Infill is usually printed in a regula...
Insufficient Retractions

It may be tempting here to improve...

Blobs and 3D Printing Zits
Blobs and 3D print zits on the outsid...
Infill Poking Through Outline

At a first glance, the blobs in th...

Scratches on Top Layers

The long scratch visible on the to...

Gaps & Holes
This is a common fault and there are ...
Small Parts & Features Not Printing

When trying to print with a 0.4mm ...

Lines On The Side Of Your Prints

Above pictures shows wobbly walls ...

Temperature Variations

These variations in layers are of...

Vibrations and 3D Printing Ringing
Good 3D printers are like good speake...
Dimensional Accuracy Of Your Prints
To achieve true dimensional accuracy ...
Circles Are Not Round

Oval circles instead of round ones...

Leaning Prints

This print is leaning to the right...

Poor Surface Quality Above Supports

We’re looking at the bottom of an ...

Failing Supports

In this picture we see several ind...

Poor Bridging

Saggy lines in this picture show p...

Stringy & Droopy Overhangs

Here we’re looking at a droopy ove...

Molten/Deformed Prints
If the prints coming from your printe...
Burnt Stuff Dripping On Your Print
See the drop of brown molten ooze on ...
Popping Noises Coming From Your Nozzle
Are you sure it is popping from the n...
Steam/Smoke Coming Out Of Your Nozzle

This is basically a continuation ...

Clicking Motors

If you hear a motor clicking it’s ...

I Cannot Print Model X

Places like Thingiverse, Youmagine...


First Layer Issues

First Layer Issues
The first layer of your print is probably the most important layer. As foundation to your whole print, it is essential in providing proper adhesion to the build plate. Many common 3D printing problems stem from a poor first layer. If your adhesion is lacking, you might end up with warped print – or no print at all besides a huge mess of tangled filament on your bed. There’s a couple of things that can wrong when printing your first layer.

First Layer Issues

The first layer of your print is probably the most important layer. As foundation to your whole print, it is...
The first layer of your print is probably the most important layer. As foundation to your whole print, it is essential in providing proper adhesion to the build plate. Many common 3D printing problems stem from a poor first layer. If your adhesion is lacking, you might end up with warped print – or no print at all besides a huge mess of tangled filament on your bed. There’s a couple of things that can wrong when printing your first layer.

Nozzle too close to the bed

Signs that your nozzle might be too close to the bed:
  • Printed line is way thinner than desired. It might get so thin it turns transparent.
  • Excess filament is squished upwards at the edges of the currently printing line creating a rough surface and wavy patterns. (You can feel the roughness when touching it carefully even during the print).
  • Filament is getting torn off the bed when the next neighbouring line is printed.
  • Finished prints are hard to remove from the print bed.
Description:
  • If your nozzle is too close to the bed, there is not enough space between nozzle and the bed to extrude the proper amount of filament. Excess filament is either squished upwards between individual printed lines or isn’t extruded at all creating additional pressure in the HotEnd.
  • Excess filament that gets squished to the sides and upwards might get torn off the bed on the next pass by the nozzle destroying adhesion and making the top of your first layer very rough to the touch.
  • Excess filament might also get picked up by the nozzle and might drip back on your print later. This is especially common for PETG.
  • If filament backs up in the HotEnd because it cannot get extruded due to the nozzle being too close to the bed, your extruder might even get jammed and start clicking.
  • Squishing your first layer too much into the bed can lead to prints that are almost impossible to remove from the build plate when done.
How to fix:
  • Adjust nozzle to bed distance either by tightening the 3 or 4 levelling screws of your printer and using thicker paper stock for manual bed levelling or by adjusting your z-offset value when using a bed levelling sensor. Make sure you’re not pressing down on your bed when levelling it.

Nozzle too far away from the print bed

Signs that your nozzle is too far away from the print bed
  • When looking at the bottom of your printed object, you can clearly make out individual lines with a noticeable gap between each line.
  • During printing the first layer, the individual lines are not touching each other.
  • There’s small gaps where the lines of the infill are not touching the outlines of the wall.
  • The shape of the extruding line is very round. With the proper distance, extruded line is slightly squished, pancake shaped.
  • Individual printed lines are barely sticking to the build plate.
  • Parts are warping off the build plate or become loose during the prints.
Description:

If your nozzle is too far from the bed there is not enough filament extruded to properly fill the space between nozzle and bed. The line currently extruding is barely making contact with the bed. Individual lines making up the first layer are not connected to their neighbours and they’re not touching the outlines of your objects wall. All this usually this leads to poor adhesion problems like warping or detaching of your object mid print.

How to fix:
  • Adjust nozzle to bed distance either by loosening the 3 or 4 levelling screws of your printer and using thinner paper stock (receipt paper is good) for manual bed levelling or by adjusting your z-offset value when using a bed levelling sensor. Make sure you’re not pressing the bed upwards while levelling manually.

Printer specific tips

  • Prusa MK2/MK2S: The Prusa’s PINDA sensor is temperature sensitive and will give false readings if the probe is heated before the mesh bed levelling. Raise your probe a good distance off the bed during the preheat before mesh levelling at the beginning of a print.
  • Creality CR10/Tevo Tornado: Both printers come with a fairly large bed. And they’re not necessarily the flattest. Try leveling the bed not at the outermost corners but rather a bit further in.
  • Wanhao i3: keep your hands well away from the bed while feeling the paper dragging during the levelling process. The stock bed frame is rather flimsy and looking at it sternly screws up the results. Repeat levelling procedure at least 3-4 times or more to make sure it stays level. Try levelling at full printing temp, use Preheat in the menu.
  • Tevo Tarantula: green stock SN04 sensor is unreliable. Level manually and keep your hands well away from the bed while feeling the paper dragging during the levelling process. The stock bed frame is rather flimsy and looking at it sternly screws up the results. Repeat levelling procedure at least 3-4 times or more to make sure it stays level. Try levelling at full printing temp, use Preheat in the menu.
  • Ultimaker 2/2+: The bed carrier flexes a lot when turning the levelling screws, especially the ones in the front. Keep hands clear. Don’t bother with the bed level assistant, just run through it and do the rest manually.

Filament specific tips

  • PLA likes to be squished more into the bed than other filament types to provide good adhesion.
  • PETG usually prints better with a higher nozzle to bed distance to avoid the nozzle picking up filament that might drip on your print later during the print. Also, the extra distance helps prevent excessive adhesion issue that for example might occur when printing on glass or PEI beds.
  • TPU and Flexible PLA will also adhere stronger than you might like if printed too close to a PEI or specialist bed surface (such as BuildTak).


Prints Sticking Too Much

Prints Sticking Too Much
Maybe less common than the opposite problem with prints not sticking or warping, but prints sticking excessively to your print bed may happen. Possible reasons and fixes include:

Prints Sticking Too Much

Maybe less common than the opposite problem with prints not sticking or warping, but prints sticking excessively to your print...
Maybe less common than the opposite problem with prints not sticking or warping, but prints sticking excessively to your print bed may happen. Possible reasons and fixes include:

Increase the nozzle to bed distance

Cooler bed

Consider printing the first layer faster and or colder, try a colder heat bed.

Reduce bed adhesion

Before printing especially sticky filaments like flex material or PETG, rub some talcum or baby powder onto your bed.

Use a release agent

Use glue stick or hairspray coating to act as “release agent”. Adding this additional film between your bed and the print will ensure that the print will detach taking away the coating with it instead of tearing up the bed surface. PETG is known to be strong enough to rip chunks out of glass plates when cooling down after a print or bonding permanently to a PEI bed.

Flexible Filaments

Flexible filaments have a habit of sticking way to well to certain bed surfaces. Add Kapton tape for flexible filaments. Peel the Kapton tape from the bed, then the tape from the bottom of your print to minimize the risk of damaging your print when trying to pry it off your bed.

Decrease extrusion multiplier

Decrease extrusion multiplier. Less presser with the material flow on the bed will lower the adhesion of the print.

Freeze it

If all else fails, put the affixed print and bed into a freezer for a few hours. The print should pop off with some light tapping once cool enough.

Warping

Warping

Warping occurs when the physical forces that come into play when a material is cooling down exceeds the adhesion strength of the printed object holding it onto your build plate. Usually it starts in corners and doesn’t stop there. Warping is increased the higher the temperature difference is within the printed object and/or the higher the difference is between printed temperature and room temperature.

To fight warping:

  • See [Print not sticking to the bed].
  • Print less hot (less temperature difference = less warping).
  • Print thinner layers.
  • Make sure you’re not setting your bed temperature above the glass transition temperature of your filament.
  • When printing ABS, use an enclosure or even a heated build chamber to increase ambient temperature, requires a heated bed
  • When printing ASA, consider using an enclosure to shield the print from drafts. Significantly reduce part cooling fans (5-10% power). ASA requires a heated bed.

If you need more info on warping, causes and fixes, you can view our article on preventing warping here.

Warping

Warping occurs when the physical forces that come into play when a material is cooling down exceeds the adhesion strength...

Warping occurs when the physical forces that come into play when a material is cooling down exceeds the adhesion strength of the printed object holding it onto your build plate. Usually it starts in corners and doesn’t stop there. Warping is increased the higher the temperature difference is within the printed object and/or the higher the difference is between printed temperature and room temperature.

To fight warping:

  • See [Print not sticking to the bed].
  • Print less hot (less temperature difference = less warping).
  • Print thinner layers.
  • Make sure you’re not setting your bed temperature above the glass transition temperature of your filament.
  • When printing ABS, use an enclosure or even a heated build chamber to increase ambient temperature, requires a heated bed
  • When printing ASA, consider using an enclosure to shield the print from drafts. Significantly reduce part cooling fans (5-10% power). ASA requires a heated bed.

If you need more info on warping, causes and fixes, you can view our article on preventing warping here.


Inconsistent Extrusion: How To Fix Under Extrusion

Inconsistent Extrusion: How To Fix Under Extrusion

3D printing under extrusion is one form of inconsistent extrusion (the other being over extrusion). The term is used when the printer fails to extrude the proper amount of filament at any given time. Unfortunately, it can have a myriad of causes. No 3d printer troubleshooting guide would be complete without the full list of causes.

The symptoms are easy to spot: you end up with weak prints that crumble, crack or tear under even slight stress, you have visible gaps in your objects, walls start becoming see through because solid areas show spongy patches instead. Here’s an attempt to classify and list possible reasons and fixes. We also have a dedicated article on under extrusion issues here.

Inconsistent Extrusion: How To Fix Under Extrusion

3D printing under extrusion is one form of inconsistent extrusion (the other being over extrusion). The term is used when...

3D printing under extrusion is one form of inconsistent extrusion (the other being over extrusion). The term is used when the printer fails to extrude the proper amount of filament at any given time. Unfortunately, it can have a myriad of causes. No 3d printer troubleshooting guide would be complete without the full list of causes.

The symptoms are easy to spot: you end up with weak prints that crumble, crack or tear under even slight stress, you have visible gaps in your objects, walls start becoming see through because solid areas show spongy patches instead. Here’s an attempt to classify and list possible reasons and fixes. We also have a dedicated article on under extrusion issues here.

Under-extrusion in general

  • Make sure your filament can unspool freely from the reel.
  • Check the filament path for any blockages or areas of strong friction.
  • Verify the filament diameter is consistent. Especially very cheap filaments suffer from fluctuations in filament diameter. Too thin and there isn’t enough filament fed into the HotEnd, too thick and there might be too much friction to push through the extruder and the related filament path.
  • Check the extrusion settings in your slicer, namely filament diameter, extrusion multiplier.
  • Check proper print temperature and speed. Try printing hotter and slower.
  • Also see [filament not feeding properly].

3D printer not extruding mid-print

You’ve come back to find your 3D printer not printing anymore. This along with coming back to find a ‘birdsnest’ are the two most cliche versions of failed 3D prints. For some reason or another, your 3D printer stops extruding mid print:

  • Filament has stripped or is blocked in the extruder.
  • Filament is kinked, snapped or ran out. The filament has twisted or you got a knot on the reel.
  • Filament diameter isn’t consistent. Especially very cheap filaments suffer from fluctuations in filament diameter. Too thin and there isn’t enough filament fed into the HotEnd, to thick and there might be too much friction to push it in through the extruder and the related filament path.
  • You’re trying to print a part with too aggressive retraction 3D printing settings or excessive amount of retractions in a short period of time. Check your 3D printer retraction settings and lower total amount of retractions occurring and/or reduce retraction distance. Sometimes loosening the feeder gear idler pressure onto the filament can help.
  • Overheated stepper drivers. A lot of tinkerers like to increase the Vref of their stepper drivers, often needlessly. This could lead to overheated steppers. Also, when printing high temperature filaments in an enclosed or heated build chamber steppers tend to get considerably hotter.
  • Nozzle clogged mid print. This again can have a lot of different causes.
  • If it happens very early in the print, it might be too much back pressure because the nozzle is too close to the bed. See [nozzle too close].
  • In general: Try printing hotter or slower. But do not exceed the maximum print temperature of the filament, as it might start to deteriorate in your nozzle and clog. Very common error is to boil rigid ink PLA by exceeding the maximum print temperature.
  • Check for warping. Warped areas are closer to the nozzle increasing back pressure.
  • Monitor nozzle temperature while printing, check for high drops in print temperature.
  • Keep your nozzle clean, especially after switching between different filament types.
  • When using particle filled filaments, consider using a bigger nozzle.
  • Flex filament got stuck. Flexible filaments are difficult to print with most extruders out there, as they tend to escape the intended filament path and simply get stuck. Try printing way slower, try printing hotter (within the recommended range) and maybe even consider upgrading to a different extruder design specialised in printing flexible filaments.
  • Also see [filament not feeding properly].

Under-extrusion at the beginning of a print

Under-extrusion at the beginning of a print is common and to a point to be considered normal. It can a take a bit to get the flow of filament going, this is where using a skirt if no brim is required comes in handy.

  • Consider using a skirt as this will show how consistently the material is being laid down before you waste filament on the printed object itself.
  • Modify your start code in your slicer to add some extra priming. While you’re checking the codes, make sure you don’t have an excessive retract in your end code.
  • Often, not extruding properly at the beginning of a print is a result of the nozzle being too close to the bed or issues mentioned in the sections above.
  • Check print temperature, you might be printing too cold.
  • Also see [filament not feeding properly].

Extruding Wrong Amount Of Plastic

Extruding Wrong Amount Of Plastic

In previous chapter, we looked at [inconsistent extrusions]. Here are some more extrusion issues:

Extruding Wrong Amount Of Plastic

In previous chapter, we looked at [inconsistent extrusions]. Here are some more extrusion issues:

In previous chapter, we looked at [inconsistent extrusions]. Here are some more extrusion issues:

Constant over-extrusion

If you’re finding your 3D printer over extruding constantly, that is: it is pushing too much plastic, it is best to recalibrate the steps/mm value of your extruder to ensure your extruder delivers the proper amount of filament requested. Once the steps per mm are set correctly, the next step to a proper calibration is to set your extrusion multiplier (also called feed rate) properly to combat over extrusion 3D printing.

Both steps/mm as well as extrusion multipliers are filament dependent and might even change over time. Or it could simply be a matter of you changed the extrusion multiplier for a recent print and forgot to reset it in your slicer.

Temperature can play a factor in 3D printing over extrusion, so as always ensure you’re printing at the cooler end of the spectrum for your material.

Constant under-extrusion

If you printer is constantly under-extruding, that is it is not pushing enough plastic, it is best to recalibrate the steps/mm value of your extruder to ensure your extruder delivers the proper amount of filament requested. Once the steps per mm are set correctly, the next step to a proper calibration is to set your extrusion multiplier (also called feed rate) properly. Both steps/mm as well as extrusion multipliers are filament dependent and might even change over time.

Or it could simply be a matter of you changed the extrusion multiplier for a recent print and forgot to reset it in your slicer. Also, very often the root cause for constant under-extrusion is partially clogged nozzle. Cleaning out your nozzle would be a good start. Also check the previous chapters [inconsistent extrusion] and [filament not feeding properly].

Temporary under-extrusion

We’re under-extruding causing gaps in 3D print, but only sporadically here and there during the print. Sometimes even so little it is hard to notice at all. Still, check the previous chapters [inconsistent extrusion] and [filament not feeding properly].

Under-extrusion after retraction

During a 3D printing retraction, especially with very aggressive retract settings, there could be not enough filament in the nozzle to properly start the print again at the end of the travel move. To fix:

  • Lower your retraction length.
  • Give it a bit a extra restart distance to prime the nozzle after the retraction.

A series of very fast retracts can chew up a filament so that the feeder gear can slip on the damaged filament once you start extruding again. To fix:

  • Slow down the retraction speed.
  • Check that the feeder pinch wheel tension is correct.

Filament Not Feeding Properly

Filament Not Feeding Properly

Proper operation depends on your extruder being able to feed the correct amount of material at any given time. Any messing with the feed of filament will likely ruin your print. Here’s what to look out for. But, first, listen closely to the noise your extruder motor is making, it’ll give you a clue.

Filament Not Feeding Properly

Proper operation depends on your extruder being able to feed the correct amount of material at any given time. Any...

Proper operation depends on your extruder being able to feed the correct amount of material at any given time. Any messing with the feed of filament will likely ruin your print. Here’s what to look out for. But, first, listen closely to the noise your extruder motor is making, it’ll give you a clue.

Extruder motor is clicking

A stepper motor will start clicking when it is skipping steps. That is in the case of an extruder motor when the force required to push the filament further is higher than the motors strength. Possible reasons include:

Deformed filament

Remove the filament from the extruder and check how it looks. Is it deformed, as in no longer round but crushed so that its diameter is now wider than it should be? If so you might want to try to decrease the idler pressure on your feeder gear.

Conversely, if the filament is not crushed, but just has a gouge taken out of it where the hob gear has repeatedly slipped, increasing the idler pressure may restore correct filament feeding. Just don’t overdo it or the problems listed above will likely happen.

Reduce strain
This problem is made worse when you’re trying to print something that requires a lot of retractions in a short amount of time. Try to reduce the amount of retractions or set your retracts to be less aggressive.
Reduce friction
Check your filament path for excess friction.
Worn PTFE liner
A lot of HotEnds, even in direct extruders, include a PTFE liner, i.e. a short piece of Bowden tube somewhere between nozzle and heat break. In most Bowden style extruders, the tube extends all the way from the extruder down into the HotEnd. If this inner tube is worn or degraded (happens when printing too hot, usually above 260°C) the friction increases and might be too much for the extruder stepper motor to overcome.
Check PTFE liner gap

If the HotEnd uses a PTFE liner and it is frayed or has been cut at an angle. Any gap there will lead to clogs sooner or later as the melted filament will leak out around the outside of the liner causing the liner’s inner diameter to deform and reduce.

When using an Ultimaker: check the PTFE coupler in your HotEnd. It is considered consumable and will need replacement on a regular basis.

Nozzle clogged
Your nozzle or HotEnd is clogged. This could be any of the benign reasons like printing too cold, or too hot, or too fast, using too much retraction or nozzle to close to the bed, etc. But there are also some mechanical things to look into, especially if the problem reappears after you cleaned it.
To note:
If your HotEnd wasn’t assembled properly, a common point of failure here is if the nozzle is tightened against the heater block instead of tightening it against the heat break.
Pro tip:
Increase the Vref of the extruder stepper, giving it a little more power to maybe push a bit stronger without skipping. But do keep an eye on the motor and driver temperatures if you do.

Bowden tube issues

If you’re using a Bowden extruder, these are also common points of failure:

  • There’s debris in the Bowden tube.
  • The Bowden tube is worn in the inside and has increased friction.
  • The bend radius of the Bowden tube is too high. Consider a longer tube or straighten its path.
  • A common issue with Bowden style extruders is when the tubing isn’t pushed all the way into the HotEnd. Or the end of the tube is frayed or has been cut at an angle. Any gap there will lead to clogs sooner or later as the melted filament leaks out around the tube causing it to deform.

If the extruder isn’t clicking

But still no filament is coming out of the nozzle it is very likely we have a problem right around the feeder part of the extruder.

Check extruder is clear
Remove the filament from the extruder. Could be a bit tricky. Check its shape. Chances are the feeder gear has eaten away a good part of the filament and dug itself in, i.e. no filament can be transported, as there is nothing left for the gear to grip. This is usually a consequence of a blockage that happened before. So, once you cleaned this feeder section of the extruder of any debris and fed fresh filament in, you’ll still have to find the cause for the blockage that was responsible for this in the first place.
Adjust idler pressure spring
Another reason why filament might not get transported properly if the idler isn’t exerting enough pressure to push the filament against the feeder gear. A lot of feeders have a spring that can be tensioned to increase the idler pressure. Or this spring might be missing, broken or collapsed.
Check feeder gear

While at it, check that the teeth of the feeder gear haven’t worn. A lot of these gears are made from brass and won’t last forever. Teeth might even be missing entirely.

Also, the teeth could be gunked up with debris stripped from the filament during normal operation and need to be cleaned - small brass wire brush is ideal for this - but PLEASE, for your own sanity, make sure that no pieces of the brush or debris get into the HotEnd or the path leading to it. Metal particles in a HotEnd and nozzle are not something you ever want to happen.

Check thermister
Most firmware versions today will deactivate the extruder motor if the nozzle is not up to temperature. So, it won’t click and not feed anything either. Take a peek at your nozzle temperature, maybe your thermistor stopped working?

Motor is wildly turning back and forth even with no filament loaded:

This could be a sign of a loose motor cable either at the board or the motor end, a broken cable or broken or loose pin in the connector. Or a failed motor. Or wrong cable configuration with leads swapped. If this happens, stop what the printer is doing immediately, let it cool down and power it off!

A broken wire on a stepper can easily destroy a driver chip by creating high voltage spikes as the stepper is connected and disconnected (the same damage can occur if you manually disconnect or reconnect a stepper motor while the printer is powered-up).


Extruder Is Grinding Filament

Extruder Is Grinding Filament

The picture on the left shows a section of filament after it was manually pulled out of the extruder. You can see the dent where the drive gear dug in deep into the filament, making further transport of this filament impossible. It had to be removed manually with a bit of force.

This usually happens when the pressure inside the HotEnd gets too high or if there is anything blocking filament transport. 3D printer filament grinding can be caused by:

  • Deformed filament or filament diameter too thick.
  • Filament not unspooling from the spool, kinked, knotted or twisted on the spool.
  • Too much friction in filament path (especially common with worn or dirty Bowden tubes).
  • Trying to extrude too much material for the nozzle size.
  • Partial (or full) clog in the nozzle or HotEnd .
  • The nozzle being too close to the bed (bed levelling is off) or too close to the previously printed layer (warping).
  • Trying to print too cold.
  • Trying to print too fast.

Extruder Is Grinding Filament

The picture on the left shows a section of filament after it was manually pulled out of the extruder. You...

The picture on the left shows a section of filament after it was manually pulled out of the extruder. You can see the dent where the drive gear dug in deep into the filament, making further transport of this filament impossible. It had to be removed manually with a bit of force.

This usually happens when the pressure inside the HotEnd gets too high or if there is anything blocking filament transport. 3D printer filament grinding can be caused by:

  • Deformed filament or filament diameter too thick.
  • Filament not unspooling from the spool, kinked, knotted or twisted on the spool.
  • Too much friction in filament path (especially common with worn or dirty Bowden tubes).
  • Trying to extrude too much material for the nozzle size.
  • Partial (or full) clog in the nozzle or HotEnd .
  • The nozzle being too close to the bed (bed levelling is off) or too close to the previously printed layer (warping).
  • Trying to print too cold.
  • Trying to print too fast.

Extruder Is Crushing Filament

Extruder Is Crushing Filament

This piece of filament in the picture on the left is clearly deformed, it is no longer round. It was crushed between the idler and feeder drive gear. This problem is related to [Extruder grinding filament] and is usually a precursor of that. This happens a lot when:

  • The feeder gear idler pressure is way too high, deforming the filament while it passes through the feeder.
  • The same part of filament is getting retracted, pushed forward, retracted multiple times. Printing something with a lot of retractions in short order will wreak havoc on the filament, especially if the feeder idler pressure is squeezing the filament a bit too tight.

Extruder Is Crushing Filament

This piece of filament in the picture on the left is clearly deformed, it is no longer round. It was...

This piece of filament in the picture on the left is clearly deformed, it is no longer round. It was crushed between the idler and feeder drive gear. This problem is related to [Extruder grinding filament] and is usually a precursor of that. This happens a lot when:

  • The feeder gear idler pressure is way too high, deforming the filament while it passes through the feeder.
  • The same part of filament is getting retracted, pushed forward, retracted multiple times. Printing something with a lot of retractions in short order will wreak havoc on the filament, especially if the feeder idler pressure is squeezing the filament a bit too tight.

Other Filament Issues

Other Filament Issues
The quality and state of your filament plays a vital role to the success and quality of your prints. Here are some common issues with filament to look out for:

Other Filament Issues

The quality and state of your filament plays a vital role to the success and quality of your prints. Here...
The quality and state of your filament plays a vital role to the success and quality of your prints. Here are some common issues with filament to look out for:

Inconsistent diameter

If your filament diameter is not consistent, you’ll notice it in your prints. Sections that are too thin will produce under-extrusions or fail to get gripped and transported by the drive gear. Parts that are too thick will over-extrude or even get stuck somewhere along the filament path. High quality filament has a consistent diameter from beginning to the end of the spool.

Filament slipping

There could be a thin section on a spool with inconsistent diameter. Or maybe your extruder’s feeder idler pressure is not high enough or possibly the drive gears teeth are worn or gunked up.

Moisture absorbtion

Filament will absorb moisture, Nylons and PVA especially, but it can also happen with ‘normal’ filament, even PLA, it just takes longer. Make sure you store your filament in sealed bags with freshly charged desiccant.

Stale filament

Filament can go stale, especially after it absorbed moisture or was exposed to UV/sunlight for quite a while.

Brittle filament

Brittle filament, breaking or snapping - Stale filament, but also some of the more brittle formulas, especially for PLA or PMMA, might snap when it is passing the drive gear or is bent for example in a Bowden tube at a higher angle. [A good test for the ‘freshness’ of PLA filament is to bend it to 90 degrees (at room temperature ~20°C) with your fingers. If it snaps, it is stale. Pull 10-15 meters off the reel and try again. You might be lucky - it may only be the top layers that have gone stale]

Clogged Nozzle

Clogged Nozzle
Clogged extruders happen. Here are why they happen, how to prevent them and what to do if you have one.

Clogged Nozzle

Clogged extruders happen. Here are why they happen, how to prevent them and what to do if you have one....
Clogged extruders happen. Here are why they happen, how to prevent them and what to do if you have one.

Why extruders clog

  • Either you printed too hot or had your nozzle distance to close to your bed.
  • You forgot and left your printer sitting idle with a heated nozzle.
  • You might have had dust & dirt pulled into the now clogged extruder HotEnd.
  • You received some contaminated filament (some cheap stuff is full of things that shouldn’t be in there).
  • You tried to print with Wood filament (we had some of the best clogs ever when printing with wood filament!).
  • Prevent clogged extruder

    Here is some advice that will help you avoid these problems:

    • Prevent any accumulation in your nozzle by doing preemptive maintenance.
    • Use a filament filter. You can print your own, it’s simple.
    • Make sure never to exceed the recommended HotEnd temperature for whatever filament you’re trying to use. Cooked filament blocks nozzles.
    • Use particle filled filaments in nozzle with at least 0.5mm diameter or greater.
    • We recommend Floss, a high-performance cleaning filament, to make preventive maintenance easy. Extrude a bit of rigid.ink Floss on a regular basis, like between material changes and the risk of clogs should be lessened drastically. Especially when switching from a high temp material to low temp one , or when cleaning up after particle filled filaments.

    Unblock the nozzle

    Prevention only gets you so far. If you do have a fully blocked nozzle, things will get a bit trickier. Here are some tips to help get your nozzle going again – but do check for your printer manufacturer’s recommendations first:

    • You can try to dislodge the block in your nozzle with an acupuncture needle, hypodermic needle or an uncoated high-e guitar string. Once you got the clog dislodged, try cleaning filament.
    • A highly effective yet brutal (if done improperly) way to clean a blockage are so call cold pulls or the “atomic method”. We’ve got an article on nozzle cleaning methods here.
    • Another equally brutal way is to torch your nozzle with a blowtorch (after removing it from the printer first!).
    • With ABS you could try to soak it in an acetone bath overnight.
    • You can do the same for PLA with a bath of ethyl acetate.

    Other Blockages

    Unfortunately, the nozzle isn’t the only place where clogs might occur. If no filament is coming out of the nozzle anymore the actual blockage might not be in the nozzle itself. You’ll have to check the whole filament path, starting from the feeder to the nozzle.

    • Often, blockages occur right after the drive gear, especially when using flexible filaments.
    • Bowden tubes like to gather debris, increasing friction, causing blockages. Inspect, clean and replace as needed.
    • Another notorious spot is where the Bowden tube in Bowden extruders (or the PTFE liner tube in certain HotEnds) meets up with the metal bits. If the tip of the tube is frayed, dented, carbonised or cut at anything but a 90° angle, this is inviting trouble. Also make sure your tube is seated firmly as far in as possible. If the tube moves, for example during retractions, chances for a blockage increase.
    • Right around the heat break. Usually a sign of insufficient HotEnd cooling or too high of a retraction distance.

    Also read our chapter [Filament not feeding properly]

    Other Blockages

    Unfortunately, the nozzle isn’t the only place where clogs might occur. If no filament is coming out of the nozzle...

    Unfortunately, the nozzle isn’t the only place where clogs might occur. If no filament is coming out of the nozzle anymore the actual blockage might not be in the nozzle itself. You’ll have to check the whole filament path, starting from the feeder to the nozzle.

    • Often, blockages occur right after the drive gear, especially when using flexible filaments.
    • Bowden tubes like to gather debris, increasing friction, causing blockages. Inspect, clean and replace as needed.
    • Another notorious spot is where the Bowden tube in Bowden extruders (or the PTFE liner tube in certain HotEnds) meets up with the metal bits. If the tip of the tube is frayed, dented, carbonised or cut at anything but a 90° angle, this is inviting trouble. Also make sure your tube is seated firmly as far in as possible. If the tube moves, for example during retractions, chances for a blockage increase.
    • Right around the heat break. Usually a sign of insufficient HotEnd cooling or too high of a retraction distance.

    Also read our chapter [Filament not feeding properly]


    Stringing and Oozing

    Stringing and Oozing
    3D Printer Stringing and nozzle oozing are two common 3D printer problems that usually share the same root cause. Printing too hot and using inadequate retraction settings. In general: printing colder helps stringy 3D prints. Here’s what else you can do to eliminate both:

    Stringing and Oozing

    3D Printer Stringing and nozzle oozing are two common 3D printer problems that usually share the same root cause. Printing...
    3D Printer Stringing and nozzle oozing are two common 3D printer problems that usually share the same root cause. Printing too hot and using inadequate retraction settings. In general: printing colder helps stringy 3D prints. Here’s what else you can do to eliminate both:

    Increase retraction distance

    Increase the retraction distance in your slicer. There’s usually a limit for how far up you can retract filament before you’re running into other issues, but as a general rule of thumb: up to 3mm is ok for most direct extruders, 4-6mm should be ok for long Bowden systems.

    Increase retraction speed

    Increase the retraction speed. Maximum speed depends entirely on your extruder, so it is hard to come up with a valid recommendation, when in doubt try up to 40mm/s. Check with your printer manufacturer.

    Arrange prints closer

    Long travel distances tend to make your 3D print stringy, so if you can rearrange the objects on the bed, this could help against stringing 3D printing.

    Increase travel speed

    Try increasing your travel speed in your slicer. Less time to ooze between layer points.

    Calibrate steps & multiplier

    Whenever you encounter any sort of extrusion issues, make sure your basics are covered - properly calibrated extruder steps/mm and extrusion multiplier are key to nice prints. Over-extrusion encourages 3D print stringing.

    Increase cooling

    Up those cooling fans, works especially well to combat PLA stringing.
    If all else fails, try printing single objects instead of placing multiple objects on the build plate. This eliminates all travel moves between multiple objects and will cut down on 3D printing stringing & oozing between multiple objects.

    Overheating

    Overheating

    The tip of this (supposed) spike got molten because of overheating. Or lack of cooling. Here’s how to fix one of the ugliest form of bad 3D prints:

    • The main cause of the problem is insufficient cooling. If you can, turn the part cooling fan speed up higher. Usually, especially with PLA this is not an option, because we’re generally already printing at 100% fan speed.
    • Try printing colder to begin with.
    • Print slower, giving the print more time to cool down. Consider the 15 second rule: the time for the nozzle coming back to the same point on your object should not be less than 15s.
    • If your slicer supports it, set a minimum time per layer to ensure proper cooling. This usually results in the slicer dynamically slowing down the print speed to ensure the minimum layer time, which, in this particular case, won’t help all that much.
    • Pro tip: you could add a pause to the layer change script and park the nozzle away from the object for a few seconds.
    • Workaround: try printing two copies of the object at the same time, the travel moves between the 2 objects will increase the layer time and allow for more cooling.

    Overheating

    The tip of this (supposed) spike got molten because of overheating. Or lack of cooling. Here’s how to fix one...

    The tip of this (supposed) spike got molten because of overheating. Or lack of cooling. Here’s how to fix one of the ugliest form of bad 3D prints:

    • The main cause of the problem is insufficient cooling. If you can, turn the part cooling fan speed up higher. Usually, especially with PLA this is not an option, because we’re generally already printing at 100% fan speed.
    • Try printing colder to begin with.
    • Print slower, giving the print more time to cool down. Consider the 15 second rule: the time for the nozzle coming back to the same point on your object should not be less than 15s.
    • If your slicer supports it, set a minimum time per layer to ensure proper cooling. This usually results in the slicer dynamically slowing down the print speed to ensure the minimum layer time, which, in this particular case, won’t help all that much.
    • Pro tip: you could add a pause to the layer change script and park the nozzle away from the object for a few seconds.
    • Workaround: try printing two copies of the object at the same time, the travel moves between the 2 objects will increase the layer time and allow for more cooling.

    Elephants Foot

    Elephants Foot

    Classic problem in 3D printing. We have a flared out 1st layer, making our parts too big. Followed by a concave indentation of the next few lines before things straighten out as the heat radiating from the heat bed diminishes.

    • Increase nozzle to bed distance slightly.
    • Maybe reduce extrusion width for the first layer.
    • Lower the bed temperature (stay well below glass transition temperature of the filament you’re printing, i.e. no more than 50°C for rigid.ink PLA).

    Elephants Foot

    Classic problem in 3D printing. We have a flared out 1st layer, making our parts too big. Followed by a...

    Classic problem in 3D printing. We have a flared out 1st layer, making our parts too big. Followed by a concave indentation of the next few lines before things straighten out as the heat radiating from the heat bed diminishes.

    • Increase nozzle to bed distance slightly.
    • Maybe reduce extrusion width for the first layer.
    • Lower the bed temperature (stay well below glass transition temperature of the filament you’re printing, i.e. no more than 50°C for rigid.ink PLA).

    Walls Caving In

    Walls Caving In

    In this picture, we’re looking at a part of a wall that has been crushed inwards. In essence, this is the same problem as Elephants foot, sans the flared out first layer. This was a single 0.4mm outline wall printed a tad too hot with a heat bed set at an excessive 60°C. The weight of the subsequent layers crushed the lower layers that never had a change to fully harden.

    • Print cooler.
    • Lower bed temperature (stay well below glass transition temperature of the filament you’re printing, i.e. no more than 55°C for rigid.ink PLA).
    • You might try to increase the cooling fan speed if you can.

    Walls Caving In

    In this picture, we’re looking at a part of a wall that has been crushed inwards. In essence, this is...

    In this picture, we’re looking at a part of a wall that has been crushed inwards. In essence, this is the same problem as Elephants foot, sans the flared out first layer. This was a single 0.4mm outline wall printed a tad too hot with a heat bed set at an excessive 60°C. The weight of the subsequent layers crushed the lower layers that never had a change to fully harden.

    • Print cooler.
    • Lower bed temperature (stay well below glass transition temperature of the filament you’re printing, i.e. no more than 55°C for rigid.ink PLA).
    • You might try to increase the cooling fan speed if you can.

    Curling and Rough Corners

    Curling and Rough Corners

    This beams corners in the picture to the left is the classic test case to demonstrate 3D print curling. Curling as well as rough corners are another symptom of printing to hot – or insufficient cooling. Printer curling happens a lot when printing overhangs – or in corners. Rough corners are basically corners that are curling upwards.

    To fix 3D printing curling:

    • Print colder.
    • Print slower to give the printed line more time too cool.
    • Increase your fan speed.
    • When printing in an enclosure: open all doors/panels to lower ambient temperature.
    • Workaround: Try a different layer height. In the classic benchy case, printing the benchy at a 0.2mm layer height usually makes the problem disappear while it is really apparent when printing the benchy with 0.1mm layers. In other cases, a lower layer height works better.
    • Pro tip: Increase overall cooling capabilities by adding more fans, optimizing fan duct design.

    Curling and Rough Corners

    This beams corners in the picture to the left is the classic test case to demonstrate 3D print curling. Curling...

    This beams corners in the picture to the left is the classic test case to demonstrate 3D print curling. Curling as well as rough corners are another symptom of printing to hot – or insufficient cooling. Printer curling happens a lot when printing overhangs – or in corners. Rough corners are basically corners that are curling upwards.

    To fix 3D printing curling:

    • Print colder.
    • Print slower to give the printed line more time too cool.
    • Increase your fan speed.
    • When printing in an enclosure: open all doors/panels to lower ambient temperature.
    • Workaround: Try a different layer height. In the classic benchy case, printing the benchy at a 0.2mm layer height usually makes the problem disappear while it is really apparent when printing the benchy with 0.1mm layers. In other cases, a lower layer height works better.
    • Pro tip: Increase overall cooling capabilities by adding more fans, optimizing fan duct design.

    Cracking or Layer Separation

    Cracking or Layer Separation

    Cracking occurs when 3D printing layers separate because of the forces exerted on the print when layers cool at a different rate. Warping forces exceed the layer adhesion strength and the layers simply separate. When printing high temperature materials like ABS or ASA, layers not sticking together are often caused by cold air hitting the print. Whereas if you’re finding lower temp materials like PLA layers not sticking together, this poor layer adhesion is likely caused by printing too cold.

    On a first glance, it can be tricky to differentiate between cracking and temporary under-extrusion , as both leave gaps in layers or leave the print looking like it’s missing layers. Best way to tell them apart is: cracked layers are clean cuts and might show a bit of an upwards bend or warp, while under-extrusion tends to leave a spongy material deposition in the cracks. Possible resolutions for 3D printing layer separation include:

    Cracking or Layer Separation

    Cracking occurs when 3D printing layers separate because of the forces exerted on the print when layers cool at a...

    Cracking occurs when 3D printing layers separate because of the forces exerted on the print when layers cool at a different rate. Warping forces exceed the layer adhesion strength and the layers simply separate. When printing high temperature materials like ABS or ASA, layers not sticking together are often caused by cold air hitting the print. Whereas if you’re finding lower temp materials like PLA layers not sticking together, this poor layer adhesion is likely caused by printing too cold.

    On a first glance, it can be tricky to differentiate between cracking and temporary under-extrusion , as both leave gaps in layers or leave the print looking like it’s missing layers. Best way to tell them apart is: cracked layers are clean cuts and might show a bit of an upwards bend or warp, while under-extrusion tends to leave a spongy material deposition in the cracks. Possible resolutions for 3D printing layer separation include:

    Lower layer height

    You could be trying to print using a layer height that is too high for your nozzle. Maximum layer height should not exceed 75% of your nozzle size (i.e. 0,3mm for a 0,4mm nozzle).

    Increase temperature

    Getting ABS poor layer adhesion or other higher temperature materials? You are printing too cold. Increase printing temperature.

    Reduce cooling

    Slow down or turn off your part cooling fan speed. Avoid sudden large increases in fan speed like when going into bridging mode. We want to avoid drastic temperature changes.

    Use an enclosure

    Protect your print from drafts of cold air. If you’re not using a printer that is enclosed, build your own enclosure around it. This works especially well for ABS and ASA.

    Especially ABS and ASA are highly susceptible to 3D printer layer separation due to cold air hitting the print before it has cooled down fully. When printing rigid.ink ASA, use minimal fans at around 5-20% fan speed.

    No fans for rigid.ink ABS. rigid.ink ABS prints best in a fully enclosed and even heated chamber. rigid.ink ASA is less demanding and works fine in an unheated enclosure or even on an open printer with a simple draft shield.

    Round the edges

    If after these changes you’re still getting 3D print problems with layers separating it may be worth reducing the stress on the corners of the print by rounding the model, reducing the stress on the edges. You’ll notice sharp corners (like in the image above) will crack first as the stress here is greater.

    Change filament

    Still getting poor layer adhesion PLA? Some filaments simply have less layer adhesion than others. If you’ve tried all the tips above you may need to seek better quality filament that has solid 3D printing layer adhesion.

    Layers Shifting & Misaligned Layers

    Layers Shifting & Misaligned Layers
    Some 3D printing issues appear as completely random and isolated events. While printing this object, 3 layer shifts occurred. The whole print shifted to the right, causing misaligned layers and ruining the print. Here are the likely resolutions for your 3D printer shifting layers:

    Layers Shifting & Misaligned Layers

    Some 3D printing issues appear as completely random and isolated events. While printing this object, 3 layer shifts occurred. The...
    Some 3D printing issues appear as completely random and isolated events. While printing this object, 3 layer shifts occurred. The whole print shifted to the right, causing misaligned layers and ruining the print. Here are the likely resolutions for your 3D printer shifting layers:

    Slow it down

    You’re printing too fast. Trying to print too fast will cause the motors to skip, resulting in 3D printing layer shifting.

    Pro tip: check your jerk and acceleration settings as well.

    If also warping or curling

    If you’re also experiencing warping or curling, it could be that the HotEnd simply crashed into a section that has curled upwards. This picture however does not show any signs of warping or curling.

    Check filament is free

    A temporary problem with the filament not unspooling cleanly (a knot or tangles on the spool) might have blocked the movement of the (direct drive) extruder causing your 3D printer shifting layers.

    Printer lubrication

    You’ve got mechanical friction on this axis (the X-axis in this picture). Check if your printer moves freely along this axis, clean and lubricate the mechanical parts like smooth rods, lead-screws or rails and check for broken bearings.

    Check belts & pulleys

    Check your belts and pulleys for proper tension.

    Pro tip:

    Increase the Vref for this stepper motor to give it a bit more strength

    Prusa MK2 Specific:

    If you’re using a Prusa MK2(S) disable silent mode to avoid 3D printing errors like these.

    Layers Missing or Skipped Layers

    Layers Missing or Skipped Layers

    Most likely the layer isn’t missing, but due to a mechanical issue with your Z-axis, there was an uneven step when moving up to the next layer. Can easily be mistaken for [under-extrusion] or [cracking]. Here's what you can do about it:

    • Reduce the Z-axis movement speed in your slicer settings.
    • Make sure your Z-axis can travel freely. In some case, if the filament doesn’t unspool smoothly from the reel, Z-axis travel can be blocked or in a direct drive extruder setup the extruder motor might yank the extruder upwards.
    • Check your Z-axis, Clean and lubricate your smooth rods, rails, lead-screw etc. and look for broken bearings. If the error occurs exactly on the same layer in repeated prints, there could also be an issue with a bent or misaligned lead screw.
    • Pro Tip: check acceleration and jerk settings for the Z-axis.
    • Check the exact resolution of your Z-axis (motor steps and properties of the lead-screw) and set layer heights to use full steps. Sometimes, a 0.12 layer prints nicer than a 0.1mm.
    • If this is a newly assembled DIY printer kit, look into the microstepping behaviour of your stepper drivers. If this is a pre-built machine, contact the manufacturer for hardware support.

    Layers Missing or Skipped Layers

    Most likely the layer isn’t missing, but due to a mechanical issue with your Z-axis, there was an uneven step...

    Most likely the layer isn’t missing, but due to a mechanical issue with your Z-axis, there was an uneven step when moving up to the next layer. Can easily be mistaken for [under-extrusion] or [cracking]. Here's what you can do about it:

    • Reduce the Z-axis movement speed in your slicer settings.
    • Make sure your Z-axis can travel freely. In some case, if the filament doesn’t unspool smoothly from the reel, Z-axis travel can be blocked or in a direct drive extruder setup the extruder motor might yank the extruder upwards.
    • Check your Z-axis, Clean and lubricate your smooth rods, rails, lead-screw etc. and look for broken bearings. If the error occurs exactly on the same layer in repeated prints, there could also be an issue with a bent or misaligned lead screw.
    • Pro Tip: check acceleration and jerk settings for the Z-axis.
    • Check the exact resolution of your Z-axis (motor steps and properties of the lead-screw) and set layer heights to use full steps. Sometimes, a 0.12 layer prints nicer than a 0.1mm.
    • If this is a newly assembled DIY printer kit, look into the microstepping behaviour of your stepper drivers. If this is a pre-built machine, contact the manufacturer for hardware support.

    Weak or Under-Extruded Infill

    Weak or Under-Extruded Infill

    Your 3D printing infill looks weak or under-extruded (spongy in appearance). While you may get away with poor infill not affecting the external appearance of your 3D print quality, but it provides almost no stability to the print.

    So although in some instances it could be one of those problems with 3D printing that you can live with, it can be an early warning sign of worsening under extrusion.

    Weak or Under-Extruded Infill

    Your 3D printing infill looks weak or under-extruded (spongy in appearance). While you may get away with poor infill not...

    Your 3D printing infill looks weak or under-extruded (spongy in appearance). While you may get away with poor infill not affecting the external appearance of your 3D print quality, but it provides almost no stability to the print.

    So although in some instances it could be one of those problems with 3D printing that you can live with, it can be an early warning sign of worsening under extrusion.

    Reduce extrusion settings

    Most slicers increase the infill 3D printing speed or using a bigger extrusion multiplier or line width than regular outlines. This setting is often proportionally set by applying a multiplier to your general 3D printer settings.

    If you’re pushing your printer to its limits in speed and extrusion volume, the infill is the most likely place where it starts to fail first. Therefore, either reduce your general extrusion settings, or find the modifier for the infill and reduce that.

    Increase heat on faster prints

    You’re printing too cold for the desired print speed. Printing faster or at higher extrusion rates requires more heat to melt the proper amount of plastic in time.

    Lower layer height

    You’re trying to use a layer height that is too high for your nozzle or extruder. Stick to a maximum layer height of 75% of your nozzle size (i.e. 0.3mm for a 0.4mm nozzle).

    Deformed Infill

    Deformed Infill
    Infill is usually printed in a regular pattern, like in a grid, or boxes or even honeycomb structures. If you notice your infill printing deformed:

    Deformed Infill

    Infill is usually printed in a regular pattern, like in a grid, or boxes or even honeycomb structures. If you...
    Infill is usually printed in a regular pattern, like in a grid, or boxes or even honeycomb structures. If you notice your infill printing deformed:

    Infill is printed fastest

    Lower your print speed, you might be printing too fast. With most slicers, the infill is printed at the highest print speed specified, while outlines for example are printed slower. So, the first place to notice too high print speeds is often the infill.

    Decrease skip

    You may have set the infill to skip layers. If the infill deforms, decrease the skip amount.

    Increase infill extrusion width

    Your infill extrusion width may be still be set at a reduced amount (if you were trying to save weight on a previous print). Set it to 100% (or higher) to see if that helps.

    Insert diaphragm

    Some slicers allow a solid diaphragm to be printed every so many layers. This can be used to support subsequent infill layers (and as a by-product, they can increase the rigidity of the structure significantly).
    Try increasing the print temperature, printing faster requires increasing your print temperature to melt enough plastic in time.

    Tighten belts & pulleys

    Loose belts or pulleys could be responsible for a printer’s inability to perform sharp directional changes at higher speeds which could result in deformed infill patterns, especially if it consists of sharp angles.

    Insufficient Retractions

    Insufficient Retractions

    It may be tempting here to improve 3D print quality by sanding or cutting these sections from the print, and while that’s an OK fix, prevention is always the best way to fix 3D print issues.

    There’s a limit how far you can push your extruder to do retractions. If, after maxing out your retraction settings as described in the [stringing and 3D printer oozing chapter], you’re still seeing signs of insufficient retractions, you might want to consider:

    • Using non-stationary retractions in your slicer software.
    • Use an additional restart distance.
    • Print colder.
    • Try a different spool of filament.

    Insufficient Retractions

    It may be tempting here to improve 3D print quality by sanding or cutting these sections from the print, and...

    It may be tempting here to improve 3D print quality by sanding or cutting these sections from the print, and while that’s an OK fix, prevention is always the best way to fix 3D print issues.

    There’s a limit how far you can push your extruder to do retractions. If, after maxing out your retraction settings as described in the [stringing and 3D printer oozing chapter], you’re still seeing signs of insufficient retractions, you might want to consider:

    • Using non-stationary retractions in your slicer software.
    • Use an additional restart distance.
    • Print colder.
    • Try a different spool of filament.

    Blobs and 3D Printing Zits

    Blobs and 3D Printing Zits
    Blobs and 3D print zits on the outside of your model can seriously affect the looks of print. Here are a few possible causes how you can cut down on these 3D printing artefacts:

    Blobs and 3D Printing Zits

    Blobs and 3D print zits on the outside of your model can seriously affect the looks of print. Here are...
    Blobs and 3D print zits on the outside of your model can seriously affect the looks of print. Here are a few possible causes how you can cut down on these 3D printing artefacts:

    Z-Hop

    Z-Hop (lift nozzle before retraction/travel), a very popular feature in most of today’s slicers can encourage blobs right at the retraction point. There’s two ways to go about this: either try increasing your retraction or disable the Z-hop.

    Z-Scar

    At the point where the layer change happens, a small blob will appear, the so-called Z-scar (or ‘Zipper’). It is not always possible to eliminate the Z-scar entirely by adjusting retraction settings, but modern slicers give you some choices where this Z-scar appears: the default is usually for the Z-scar to appear randomly or where the slicer thinks it would be best to optimise print speed.

    Usually you get a way cleaner looking print if you instead pick a specific less noticeable location for the Z-scar yourself. Like in a corner of a print, or at least somewhere in the back. Also choosing a specific location for the Z-scar will prevent the z-scar from splattering 3D printing blobs all over the print and confines them in more or less straight line along the Z-axis.

    Dents

    3D printer blobs and zits also appear on the surface of your print in random locations if your filament absorbed too much moisture. The steam building up inside the nozzle will make the filament pop at random times which will squirt out additional plastic (then followed by a dent because of lack of filament in the nozzle).

    Infill Poking Through Outline

    Infill Poking Through Outline

    At a first glance, the blobs in the picture above might look just like your standard blobs from improper extrusion. On a second look, you’ll notice that the blobs in this picture actually match with where the infill pattern meets up with the outside wall. We’ve got infill poking through the outlines and here’s how you can get rid of it:

    • Use more outlines.
    • Tell your slicer to print the outlines before doing the infill.
    • The blobs itself are usually a result of the retraction that is occurring at this point. So, optimizing your retraction settings as well as calibrating basic extrusion parameters will help as well.
    • Reduce the infill overlap amount in your slicer.

    Infill Poking Through Outline

    At a first glance, the blobs in the picture above might look just like your standard blobs from improper extrusion....

    At a first glance, the blobs in the picture above might look just like your standard blobs from improper extrusion. On a second look, you’ll notice that the blobs in this picture actually match with where the infill pattern meets up with the outside wall. We’ve got infill poking through the outlines and here’s how you can get rid of it:

    • Use more outlines.
    • Tell your slicer to print the outlines before doing the infill.
    • The blobs itself are usually a result of the retraction that is occurring at this point. So, optimizing your retraction settings as well as calibrating basic extrusion parameters will help as well.
    • Reduce the infill overlap amount in your slicer.

    Scratches on Top Layers

    Scratches on Top Layers

    The long scratch visible on the top layer in the picture above was caused by the nozzle dragging across the top layer when moving across to go on printing the rest of the frame around it. Most likely, the 3D printing surface of that layer is over-extruded (or slightly warped or pillowed) and that’s why the nozzle scratched it in the move.

    If it indeed is a scratch. Sometimes it is hard to tell if it is really a scratch or if the line was in fact caused by the nozzle oozing onto the top surface during the move. Time to get out the magnifying glass to check.

    • One approach would be to try and fix the over-extrusion or the warp.
    • Another is to use the Z-Hop feature of your slicer. Z-Hop will lift the nozzle up a certain amount before moving across to prevent the scratch.
    • Use combing (also known as “avoid crossing outline”). With combing, the nozzle will travel along the outline instead of crossing it and going straight across your print, which will often avoid this issue entirely (though not necessarily in this example).

    Scratches on Top Layers

    The long scratch visible on the top layer in the picture above was caused by the nozzle dragging across the...

    The long scratch visible on the top layer in the picture above was caused by the nozzle dragging across the top layer when moving across to go on printing the rest of the frame around it. Most likely, the 3D printing surface of that layer is over-extruded (or slightly warped or pillowed) and that’s why the nozzle scratched it in the move.

    If it indeed is a scratch. Sometimes it is hard to tell if it is really a scratch or if the line was in fact caused by the nozzle oozing onto the top surface during the move. Time to get out the magnifying glass to check.

    • One approach would be to try and fix the over-extrusion or the warp.
    • Another is to use the Z-Hop feature of your slicer. Z-Hop will lift the nozzle up a certain amount before moving across to prevent the scratch.
    • Use combing (also known as “avoid crossing outline”). With combing, the nozzle will travel along the outline instead of crossing it and going straight across your print, which will often avoid this issue entirely (though not necessarily in this example).

    Gaps & Holes

    Gaps & Holes
    This is a common fault and there are many reasons for gaps in your print, depending on where they're located. It's worth checking all the options in this section so that you don't miss the exact cause.

    Gaps & Holes

    This is a common fault and there are many reasons for gaps in your print, depending on where they're located....
    This is a common fault and there are many reasons for gaps in your print, depending on where they're located. It's worth checking all the options in this section so that you don't miss the exact cause.

    In The Top Layer/Pillowing

    3D printer pillowing occurs when trying to print a solid layer over a coarse infill grid. Depending on your infill percentage and your layer height, it may take a lot of layers to fully close the top surface over infill to produce a nice, smooth surface. Figure at least 1mm of combined layers for your top layer as a rule of thumb. So, if you’re printing with a layer height of 0.2mm use at least 5 top layers to play it safe. Other ways to reduce 3d printing pillowing are:
    Print cooler
    Print colder or increase fan speeds. Better cooling improves bridging performance, and that’s basically what we’re doing when printing over infill.
    Higher infill percentage
    Use a higher infill percentage. More infill means smaller gaps, which are easier to cover.
    Under extrusion
    Another possible cause for gaps in your top layer is under-extrusion . See [Temporary Under-extrusion].

    Holes and gaps in floor corners

    These 3D printer errors happen where a horizontal surface meets an inclined one. The top layer(s) look like the printer could not be bothered to print all the way to the edge. Its causes are similar in nature to pillowing, but it can be more annoying to nail the exact cause when everything else is looking great!

    There are a lot of possible causes of this problem and solutions:

    Under-extrusion
    Under-extrusion - increase the extrusion multiplier /feed rate.
    Increase top layers
    Not enough top layers -increase the top layers count so you are printing at least 1mm thick.
    Print cooler
    Printing too hot - print at a lower temperature so the plastic sets in position faster. [also, see below].
    Print slower
    Printing too fast - slow down the print speed. This allows the extruded plastic to cool more before the next pass of the nozzle. If kept too warm, the layer will peel back from where it was printed.
    Increase cooling
    Not enough cooling - if at all possible, increase cooling during the printing of these parts of the object.
    More infill
    Too little infill - increasing the infill percentage will help. Also look at the Minimum Infill Length in your slicer and reduce this to allow smaller runs of infill to be printed at the edges of an object instead of being ignored.
    Infill overlap
    The infill outline overlap is too small - all slicers can set how much the infill overlaps the outlines/perimeters of the object being printed. This setting makes sure they go all the way to the edge and fuse together and so help support the layers above. Try increasing this and note the result (Too much and you will likely see the infill pattern poking through the object’s visible walls and other such surfaces).
    Outlines & Perimeters
    Not enough outlines/perimeters - these also have a support role to fill, so increase these if at all possible.
    Reduce Retraction
    Too much retraction - causes there to be gaps in positions where retractions take place, so reduce this.

    Between Infill and Outlines

    If this happens on your first layer, chances are your nozzle to bed distance is not set properly. Your nozzle is probably too far away from the bed. See chapter [First Layer Issues]. If it happens later in the print:

    • This could be a result of printing too fast.
    • It could be a sign of (temporary) under extrusion.
    • Another possibility is wrong extrusion settings in your slicer.
    • Increase your extrusion multiplier Simplify3D.
    • Increase extrusion width.
    • Increase overlap settings.

    Gaps Between Thin Walls

    When trying to print thin walls that are not multiples of your nozzle width in thickness, there is a common problem with slicers leaving a gap inside walls, severely weakening the structural strength of your wall. It is rather straightforward issue: if you’re trying to print a wall that is 0.9mm thick with a 0.4mm nozzle, an average slicer might end up using 2 lines at 0.4mm each and leave a gap of 0.1mm, as it doesn’t know a way to close the remaining 0.1mm.

    Therefore you should always strife to stick to a multiple of your nozzle width when designing thin walls to help alleviate the issue:

    Thin wall options
    A lot of slicers today have special thin wall options, make yourself familiar with them and see where they can take you.
    Adjust line width
    Adjust (not necessarily increase) line width or the amount of outlines to force your slicer to construct your wall differently.
    Increase extrusion multiplier
    You can try increasing your extrusion multiplier to close the gap by intentionally over-extruding.
    Set narrower nozzle in slicer
    You can also set a narrower nozzle diameter in your slicer settings than you actually have fitted. If used with care and balanced against the extrusion multiplier, this can overcome some situations that your favourite slicer cannot cope with.

    Small Parts & Features Not Printing

    Small Parts & Features Not Printing

    When trying to print with a 0.4mm nozzle it is hard to draw a 0.1mm line. Slicers usually give up at one point or another and won’t even try to print features that are way smaller than your nozzle width (if placed on the XY plane). Here’s what you can try to improve 3d printer quality on smaller features:

    • Check your slicer settings for thin wall options.
    • Rotate the part so the fine details are on the Z-plane and reduce your layer height if necessary.
    • Get a finer nozzle.
    • Redesign the part or scale it up so the features are big enough to be printed. There is specialised software out there that will increase wall width without changing overall part dimension, might be worth a look, especially for architectural prints this comes in handy often.

    Small Parts & Features Not Printing

    When trying to print with a 0.4mm nozzle it is hard to draw a 0.1mm line. Slicers usually give up...

    When trying to print with a 0.4mm nozzle it is hard to draw a 0.1mm line. Slicers usually give up at one point or another and won’t even try to print features that are way smaller than your nozzle width (if placed on the XY plane). Here’s what you can try to improve 3d printer quality on smaller features:

    • Check your slicer settings for thin wall options.
    • Rotate the part so the fine details are on the Z-plane and reduce your layer height if necessary.
    • Get a finer nozzle.
    • Redesign the part or scale it up so the features are big enough to be printed. There is specialised software out there that will increase wall width without changing overall part dimension, might be worth a look, especially for architectural prints this comes in handy often.

    Lines On The Side Of Your Prints

    Lines On The Side Of Your Prints

    Above pictures shows wobbly walls and very apparent layers lines almost like ripples. Besides trying to print way too fast (incl. too high acceleration and jerk settings), the root cause of these 3D printing errors are often of mechanical nature.

    • Bent or misaligned Z-axis assembly.
    • Lose pulleys.
    • Check belt tension of your X & Y axes.
    • Friction on the axes (clean and grease or oil).

    Additionally, these would be possible causes as well:

    • Big variations in temperature during printing.
    • Inconsistent extrusion.

    Lines On The Side Of Your Prints

    Above pictures shows wobbly walls and very apparent layers lines almost like ripples. Besides trying to print way too fast...

    Above pictures shows wobbly walls and very apparent layers lines almost like ripples. Besides trying to print way too fast (incl. too high acceleration and jerk settings), the root cause of these 3D printing errors are often of mechanical nature.

    • Bent or misaligned Z-axis assembly.
    • Lose pulleys.
    • Check belt tension of your X & Y axes.
    • Friction on the axes (clean and grease or oil).

    Additionally, these would be possible causes as well:

    • Big variations in temperature during printing.
    • Inconsistent extrusion.

    Temperature Variations

    These variations in layers are often a result of temperature fluctuations, while unlikely to result in a failed 3D print, they’re unsightly. You can diagnose this from layers with uneven extrusion: over extrusion and under extrusion. Best would be to try a few tethered prints while running a monitoring software like for example the free and open source Pronterface to graph the exact temperature at the nozzle during to print.

    To fix the issue:

    • Try some PID Tuning. Check YouTube, there are tons of tutorials on how to do PID tuning on various printers.
    • Check the heater cartridge leads for any breaks or lose connectors.
    • Check the Thermocouple leads for any breaks or lose connectors.
    • On E3D HotEnds, check the black Molex connector for the thermistor, or better yet, remove that connector and crimp/solder the leads instead.

    Temperature Variations

    These variations in layers are often a result of temperature fluctuations, while unlikely to result in a failed 3D...

    These variations in layers are often a result of temperature fluctuations, while unlikely to result in a failed 3D print, they’re unsightly. You can diagnose this from layers with uneven extrusion: over extrusion and under extrusion. Best would be to try a few tethered prints while running a monitoring software like for example the free and open source Pronterface to graph the exact temperature at the nozzle during to print.

    To fix the issue:

    • Try some PID Tuning. Check YouTube, there are tons of tutorials on how to do PID tuning on various printers.
    • Check the heater cartridge leads for any breaks or lose connectors.
    • Check the Thermocouple leads for any breaks or lose connectors.
    • On E3D HotEnds, check the black Molex connector for the thermistor, or better yet, remove that connector and crimp/solder the leads instead.

    Vibrations and 3D Printing Ringing

    Vibrations and 3D Printing Ringing
    Good 3D printers are like good speakers, solid and heavy, with some dampening.

    Vibrations and 3D Printing Ringing

    Good 3D printers are like good speakers, solid and heavy, with some dampening.
    Good 3D printers are like good speakers, solid and heavy, with some dampening.

    Resolutions based on settings

    • Artefacts of vibration or ringing/ghosting is usually related to printing too fast.
    • Also, could be an indication that your acceleration and jerk settings are too high. The higher the mass of your extruder, the more susceptible it is to these artefacts when printing at higher speeds. This is where Bowden extruders shine.
  • Mechanical issues

    • Loose belts or pulleys.
    • Backlash in your motion system.
    • Worn or dirty bearings or rods that cause friction in the travel.
    • The so called “stick slip” issue with linear bushings.
    • Vibration might be reduced by installing NEMA dampeners.
    • Artefacts introduced by the stepper drivers can be reduced by installing smoothers or different stepper drivers.

    Dimensional Accuracy Of Your Prints

    Dimensional Accuracy Of Your Prints
    To achieve true dimensional accuracy is one of those 3D printer issues that is not easy and requires a very well-tuned printer, solid motion systems and flawless mechanics. Here are the key factors to achieving perfect 3D printer tuning:

    Dimensional Accuracy Of Your Prints

    To achieve true dimensional accuracy is one of those 3D printer issues that is not easy and requires a very...
    To achieve true dimensional accuracy is one of those 3D printer issues that is not easy and requires a very well-tuned printer, solid motion systems and flawless mechanics. Here are the key factors to achieving perfect 3D printer tuning:

    Design considerations

    FFF 3D prints squish layers down, making them slightly wider than the 3D model. So be aware holes will be smaller and external surfaces will be slightly larger on the printed object than the CAD model.

    First layer

    Squishing your first layer into the bed will have a small impact on accuracy along the Z-axis.

    Extrusion multiplier

    Over or under-extrusion as well as an improper extrusion multiplier can cause slight dimensional inaccuracies. Get your extrusion dialed in properly. These inaccuracies are usually rather constant, i.e. independent from the size of the printed object.

    Steps / mm settings

    An increasing dimensional error (increasing with the size of the print) is usually a sign of improper steps/mm settings for your X,Y or Z axes. This can be calibrated and corrected in firmware or the printers menu.

    Printer frame

    Check the rigidity and proper alignment of your printer frame. If your frame is not true, your prints won’t be either.

    A common trend today seems to throw more and more sensor and computing power at trying to fix poor frame geometry. No amount of software beats a well setup printer. Make sure your frame is aligned well.


    Circles Are Not Round

    Circles Are Not Round

    Oval circles instead of round ones is usually a mechanical problem. Check axes, belt tension, pulleys and gears. On tiny circles only a few mm in diameter, blobs usually along the Z-scar might cause the circle to look oval instead.

    Occasionally it can be down to having differing steps/mm values entered for the X and Y axes. This can happen (rarely) by EEPROM value corruption, but usually comes down to a user-induced fault.

    Either the user has accidentally entered a different steps/mm in their slicer for one of the axes (script, or just by accident), or someone has had a bit of ‘finger-trouble’ and entered a new setting via the printer’s manual front-panel controls.

    Circles Are Not Round

    Oval circles instead of round ones is usually a mechanical problem. Check axes, belt tension, pulleys and gears. On tiny...

    Oval circles instead of round ones is usually a mechanical problem. Check axes, belt tension, pulleys and gears. On tiny circles only a few mm in diameter, blobs usually along the Z-scar might cause the circle to look oval instead.

    Occasionally it can be down to having differing steps/mm values entered for the X and Y axes. This can happen (rarely) by EEPROM value corruption, but usually comes down to a user-induced fault.

    Either the user has accidentally entered a different steps/mm in their slicer for one of the axes (script, or just by accident), or someone has had a bit of ‘finger-trouble’ and entered a new setting via the printer’s manual front-panel controls.


    Leaning Prints

    Leaning Prints

    This print is leaning to the right. It starts out ever so slightly, but increases in “momentum”. This is not layer shifting, this problem got nicknamed “Leaning”. Usually a very slight but constant or proportionally increasing deviation along one axis. In contrast: a layer shift is a sudden singular(ish) occurrence at a much bigger scale. Prints that are leaning to one side are usually caused by mechanical issues.

    • Slipping pulleys or gears or belts can cause the print to slightly shift and start leaning.
    • Friction along the axis might cause it to lose steps. Just a few steps here and there, enough to make it lean.
    • A misaligned printer frame or bed will result in a leaning print as well.

    Leaning Prints

    This print is leaning to the right. It starts out ever so slightly, but increases in “momentum”. This is not...

    This print is leaning to the right. It starts out ever so slightly, but increases in “momentum”. This is not layer shifting, this problem got nicknamed “Leaning”. Usually a very slight but constant or proportionally increasing deviation along one axis. In contrast: a layer shift is a sudden singular(ish) occurrence at a much bigger scale. Prints that are leaning to one side are usually caused by mechanical issues.

    • Slipping pulleys or gears or belts can cause the print to slightly shift and start leaning.
    • Friction along the axis might cause it to lose steps. Just a few steps here and there, enough to make it lean.
    • A misaligned printer frame or bed will result in a leaning print as well.

    Poor Surface Quality Above Supports

    Poor Surface Quality Above Supports

    We’re looking at the bottom of an object that was printed above a slicer generated support structure. It looks rough, even a bit droopy. Sometimes it is enough to print at a lower layer height to get better 3D printing quality surfaces over supports, increasing cooling or lower printing temps. Anything that increases bridging performance will help here as well, as bridging is what we’re in fact doing.

    What is actually happening there?

    Poor Surface Quality Above Supports

    We’re looking at the bottom of an object that was printed above a slicer generated support structure. It looks rough,...

    We’re looking at the bottom of an object that was printed above a slicer generated support structure. It looks rough, even a bit droopy. Sometimes it is enough to print at a lower layer height to get better 3D printing quality surfaces over supports, increasing cooling or lower printing temps. Anything that increases bridging performance will help here as well, as bridging is what we’re in fact doing.

    What is actually happening there?

    Adjust Support Gap

    Normal support structures for single extruder systems are designed in such a way so they are easy to break away from the finished print. Therefore, they intentionally leave a small gap between the support structure and the actual model that sits on top of it. The height of this gap is usually adjustable in your slicer settings. Less gap means better quality but also harder to remove.

    If the gap is too close, breaking off the supports will damage the surface of your actual object.

    Dual extrusion

    If you find yourself suffering from this problem a lot, you might want to think about getting a dual extrusion system. Printing with water soluble rigid.ink PVA or the easy to remove rigid.ink Break-Away will allow you to transition seamlessly from support to the actual model completely eliminating the gap and the problems it entails.

    Increase support density

    Support structures are usually not printed solid, but rather, like infill, use a percentage, often called support density. Increase this density to improve the surface quality of the part printed above the support.

    Rotate model

    Often, the object to be printed can be rotated on the bed so less supports are needed. Or you could split the model in half using a plane cut tool and avoid the supports entirely.

    Custom supports

    If you designed the model yourself, read up on design guidelines to reduce the need for supports in the first place, or how to place your own supports at design time.

    Failing Supports

    Failing Supports

    In this picture we see several independently failed supports. This happens. Support pillars, especially when setup using a low support density are not the most stable things and will be in increasing danger of toppling over the taller they get. Here’s what you can do:

    • Avoid isolated towers, place your supports in bigger groups.
    • Reduce printing speed for support.
    • Use higher support density and if your slicer supports it - a different support pattern.
    • If your slicer supports it, have a brim or a solid bottom layer added to your supports.

    Failing Supports

    In this picture we see several independently failed supports. This happens. Support pillars, especially when setup using a low support...

    In this picture we see several independently failed supports. This happens. Support pillars, especially when setup using a low support density are not the most stable things and will be in increasing danger of toppling over the taller they get. Here’s what you can do:

    • Avoid isolated towers, place your supports in bigger groups.
    • Reduce printing speed for support.
    • Use higher support density and if your slicer supports it - a different support pattern.
    • If your slicer supports it, have a brim or a solid bottom layer added to your supports.

    Poor Bridging

    Poor Bridging

    Saggy lines in this picture show poor bridging performance. Bridging, i.e. printing more or less long distances unsupported over thin air is tricky business. It requires different settings than regular printing, usually speed and cooling is key to the success.

    Advanced slicer software detects when bridging is required and will allow you to apply different settings for the bridge.

    • Increase extrusion multiplier for the bridge.
    • Try different speeds, slower is usually better, but results may vary.
    • Increase your fan speed for bridges. We want the material to harden quickly without drooping.
    • Make sure your slicer is actually using bridging mode. If you’re using Simplify3D, make sure bridging of outlines is enables.
    • More advanced bridging options like direction of the lines that make up your bridge or increasing the start and end zone of a bridge can help as well.
    • Better than trying to optimise bridging performance is trying to avoid bridges to begin with. If possible, reorient your part on the build plate so less bridges are required or add supports to your bridges. With supports under your bridge, it won’t be able to droop as much.

    Poor Bridging

    Saggy lines in this picture show poor bridging performance. Bridging, i.e. printing more or less long distances unsupported over thin...

    Saggy lines in this picture show poor bridging performance. Bridging, i.e. printing more or less long distances unsupported over thin air is tricky business. It requires different settings than regular printing, usually speed and cooling is key to the success.

    Advanced slicer software detects when bridging is required and will allow you to apply different settings for the bridge.

    • Increase extrusion multiplier for the bridge.
    • Try different speeds, slower is usually better, but results may vary.
    • Increase your fan speed for bridges. We want the material to harden quickly without drooping.
    • Make sure your slicer is actually using bridging mode. If you’re using Simplify3D, make sure bridging of outlines is enables.
    • More advanced bridging options like direction of the lines that make up your bridge or increasing the start and end zone of a bridge can help as well.
    • Better than trying to optimise bridging performance is trying to avoid bridges to begin with. If possible, reorient your part on the build plate so less bridges are required or add supports to your bridges. With supports under your bridge, it won’t be able to droop as much.

    Stringy & Droopy Overhangs

    Stringy & Droopy Overhangs

    Here we’re looking at a droopy overhang. Stringy prints or droopy overhangs are usually a result of printing too hot or insufficient cooling. In a way overhangs are even worse to print than bridges. As bridges have a supported start and landing zone. The overhang doesn’t, it just clings to the neighbouring line. Bonus points for recognising the 3D Benchy troubleshooting theme image above.

    • Reduce your printing temperature.
    • Increasing cooling (fan speed).
    • Tell your slicer to print the inner perimeters first before printing the outlines.
    • If you design your model yourself, avoid overhangs at an angle greater than 45°.
    • If the overhang cannot be avoided, consider using supports to hold them up.
    • Check your extrusion settings. Do the basic extrusion calibration of extruder steps/mm and extrusion multiplier.

    Stringy & Droopy Overhangs

    Here we’re looking at a droopy overhang. Stringy prints or droopy overhangs are usually a result of printing too hot...

    Here we’re looking at a droopy overhang. Stringy prints or droopy overhangs are usually a result of printing too hot or insufficient cooling. In a way overhangs are even worse to print than bridges. As bridges have a supported start and landing zone. The overhang doesn’t, it just clings to the neighbouring line. Bonus points for recognising the 3D Benchy troubleshooting theme image above.

    • Reduce your printing temperature.
    • Increasing cooling (fan speed).
    • Tell your slicer to print the inner perimeters first before printing the outlines.
    • If you design your model yourself, avoid overhangs at an angle greater than 45°.
    • If the overhang cannot be avoided, consider using supports to hold them up.
    • Check your extrusion settings. Do the basic extrusion calibration of extruder steps/mm and extrusion multiplier.

    Molten/Deformed Prints

    Molten/Deformed Prints
    If the prints coming from your printer look like somebody held a blowtorch to it, chances are you’re printing too hot. Or you do not have sufficient cooling.

    Molten/Deformed Prints

    If the prints coming from your printer look like somebody held a blowtorch to it, chances are you’re printing too...
    If the prints coming from your printer look like somebody held a blowtorch to it, chances are you’re printing too hot. Or you do not have sufficient cooling.

    Print colder. One if not the most common problem we see in tech support is people printing way too hot. We’re not sure why this is; some presume hotter temperatures will improve flow rate. Sure, there’s a bit of a give here and there especially with thermistors not being the most accurate critters to begin with, but your first check should be - are you exceeding the print temperature recommendation for the filament used?

    Check with the filament manufacturer's documentation to make sure. Just because it says “PLA” on the box, it does not mean they are all print the same! There are hundreds, possibly thousands, of different types of PLA produced across the world.

    Print Slower. Printing slower allows the heat building up in the printed object to dissipate before the next pass of the nozzle over the same area of the print.

    Check / increase fans

    Make sure your fans are working. You can try to switch to fans that are pushing more air or add more fans. Sometimes, using a desk fan as a workaround can help you untill a more streamlined solution is found.

    Cooler ambient

    Ambient temperature is too high. If your printer is enclosed, open all doors, side panels or top covers to keep the ambient temperature down. Even the best fans are inefficient if all they’re doing is moving hot air around.