Experiencing heat creep in your 3D printer isn’t fun, but there are definitely some fixes that you can try to fix this issue. This article will aim to help those going through this problem, giving the causes and solutions behind 3D printer heat creep.
The best way to fix heat creep in your 3D printer is to reduce the printing temperature, decrease your retraction length so it doesn’t pull the heated filament so far back, check that your cooling fans are working properly, increase your printing speed, and make sure the heatsink is clean.
There are some other important facts to know about heat creep to prevent it from happening in the future, so keep reading to get on top of this issue.
What is Heat Creep in 3D Printing?
Heat creep is the process of an unsteady transfer of heat throughout the hotend which interrupts the right way of the filament to melt and extrude. This may result in many issues such as clogging the extrusion path or thermal barrier tube.
Improper settings or device configurations result in increased temperature in the wrong places, which can cause the filament to soften prematurely and become swollen.
The video below does a great job of explaining clogs & jams within your 3D printer’s hotend. It closely relates to problems of heat creep in your 3D printer, so you can definitely learn a thing or two.
What Are the Causes of 3D Printer Heat Creep?
You may face the heat creep problem anytime while printing, it is important to know the causes behind this problem to get rid of it properly. Major causes of heat creep include:
- Hot Bed Temperature is Too High
- Cooling Fan is Broken or Not Working Properly
- Too High Retraction Length
- Heat sink is Dusty
- Printing Speed is Too Low
How Do I Fix 3D Printer Heat Creep?
To get rid of this problem it is recommended to reduce the heat at the beginning because its results may cause bigger problems.
Where high print temperatures is a huge problem, other factors such as printing speed and retraction length should also be calibrated perfectly to get the best results.
Even if you buy another hotend which is completely new, there are possibilities that heat creep may occur due to wrong adjustments.
All-metal hotends are proved to be more sensitive to heat creep because they lack the thermal barrier PTFE coating in the heat-resistant protection that protects the filament from extreme heat.
Therefore, it is recommended to not use all-metal hotend if you are new to the world of 3D printing.
After you find out the actual reason behind the problem, you need to fix it in the right way. Below are the solutions to each of the above-mentioned causes that may help you out.
- Reduce the Heat Bed or Printing Temperature
- Fix or Calibrate the Extruder Cooling Fan
- Reduce Retraction Length
- Clean the Heatsink
- Increase the Printing Speed
1. Reduce the Hot Bed or Printing Temperature
A lot of heat coming from the printer’s hotbed can increase the temperature to a great extent and it is recommended to decrease the temperature a little to fix the heat creeps especially when you are printing with PLA
You can change the temperature from your slicer or the printer’s filament setting which allows you to increase or decrease the temperature.
The ideal temperature with 3D printing is the coolest temperature that you can still adequately melt and extrude the filament. You don’t usually want to apply too much heat to your nozzle, especially if experiencing heat creep.
2. Fix, Replace or Calibrate the Extruder Cooling Fan
Cooling the heatsink is key to avoiding or fixing heat creep. When you can properly control the way air passes around your heatsink, it does a good job in reducing heat creep.
Sometimes the positioning of the fan and airflow doesn’t allow it to effectively pass through the heatsink. This can happen when the back mounting plate is too close, so you can try fixing a spacer between to give more space.
The cooling fan should work perfectly all the time as it is essential to provide the required air to the heatsink.
If your fan is running but still, you are facing the heat creep, check that whether the fan is tilted backward because you have to assemble the fan in a way that it throws air inside not the outside.
Go to the printer’s fan settings and check that the extruder fan is running at a high speed.
Experts suggest that the RPM (Rotations per Minute) should not be less than 4,000.
Sometimes if your fan isn’t doing its job, it’s a good idea to just replace the stock fan to something more premium. You can’t go wrong with the Noctua NF-A4x20 Fan from Amazon.
It has an award-winning design with flow acceleration channels and advanced acoustic optimization frame for very quiet operation and amazing cooling performance.
3. Reduce Retraction Length
Retraction is the process of pulling the filament back to the hotend to improve print quality. If the retraction length is set too high it is possible that melted filament which has been affected by the heat may stick to the walls of the heatsink.
If this is the actual cause, reduce the retraction length in your slicer settings. Tweak the reaction length by 1mm and see at which spot the issue is resolved. The retraction settings could be different for different types of printing materials.
I wrote a guide detailing How to Get the Best Retraction Length & Speed Settings which you might find useful with this issue. The default retraction length in Cura is 5mm, so gradually reduce that and see whether it solves the problem.
4. Clean the Dust From Heatsink and Fan
The basic function of a heatsink is to make sure that the temperature for the filament should not rise up to an extreme level. After some rounds of the printing process, the heatsink and fan can collect dust which affects its function of maintaining the temperature causing heat creep problem.
The airflow in your 3D printer, especially at the extruder needs to be freely flowing.
To fix this problem and to prevent it from happening in the future, you can remove the hotend cooling fan and clean out the dust by blowing it or using a can of pressured air to blow the dust away.
The Falcon Dust-Off Compressed Gas Duster from Amazon is a great choice to go with. It has several thousand positive ratings and has many uses around the house such as cleaning your laptop, collectibles, window blinds, and general items.
Canned air is an effective solution to remove microscopic contaminants, dust, lint, and other dirt or metal particles that may not only cause heat creep but can damage the sensitive electronic components as well.
5. Increase Printing Speed
Printing at a speed too low can cause heat creep because if the filament is flowing through the nozzle at a higher speed, there is a lack of consistency between the extruded filament from the nozzle and within the extrusion system.
To help with consistency in the flow rates, it’s a good idea to increase your printing speed gradually, then check whether this solves your problem of heat creep.
Make sure that the printing speed is calibrated perfectly because both low and high print speed can cause many printing issues.
A good idea to help calibrate your printing speed is to use a speed tower, where you can adjust different printing speeds within the same print to see the effects on model quality and other things.
Fixing 3D Printer Clogged Heat Break
Heat break can get clogged due to different reasons but fixing it is not that hard. Most of the time it can be fixed just by a simple step. Below are some of the most effective and easy to implement a solution that will help up out.
Remove the Heat Break to Push Out the Stuck Material
The video above shows an unorthodox method of clearing the clog by securing a drill bit in a vice a pushing the heatbreak’s hole through the vice.
Remove the heat break from the printer and use a drill that fits in its hole but should not be too tight. Now put the drill into the vise grip so that it doesn’t move and allow you to put high pressure on it.
Push the heat break hard on the drill until the drill passes through the hole thoroughly. After removing the stuck material use a wire brush to clean the heat break and then assemble it again at the right place.
You could also use something like a plank to secure the drill bit and do the same method.
Make sure that you are keeping safety in mind here since a lot of pressure is being used! There is also a risk of damaging the smooth inside the heatbreak.
Use High Heat to Melt the Plastic
Some people mentioned that using something like butane gas to heat up the plastic and melt it. Another user actually set the extruder temperature and removed the nozzle, then twisted a drill bit into the soft plastic which could then be pulled out in one piece.
Again, you are working with high heats here so be careful.