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Extruder Diameter Issues


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We are having some hard time getting consistent filament diameter.

The diameter we are aiming for is 1.75mm

The pellets we are working with are ULTRAMID B3S uncoloured HP Poly amide, I am unsure about what grade this is. 

The PA6 has been dried overnight in a vacuum oven. 

The best setting I have found are:

Heaters: 228 225 223 226

4.5 RMP

Fans: 0%

If the fans are running (even angled down) the nylon will quickly start sticking to the nozzle, causing it to form blobs. Because the fans are off the filament flattens slightly as it goes through the pullers.

Are there some recommended settings for PA6? The extruder doesn't seem to have inbuilt for this.  

Any advice would be greatly appreciated.

Thank you in advance.



Dear Victor,

Each grade of plastic is different, and unfortunately we have never worked with Ultramid B3S so we do not have settings for this.


- If the material starts sticking to the nozzle, this usually means that the nozzle is too cold.
This could be because heater 1 is set too low, the filament fans are pointed at the nozzle and cool it down, or the nozzle is not insulated properly. If the nozzle is too cold, it is also very difficult to get a consistent filament output.
The first things to check is making sure the fans are pointed downwards away from the nozzle, the insulation wool is properly placed around the nozzle, and the magnetic nozzle plate (black metal plate) is mounted properly.


- Flattening between the wheels : this happens when the filament is too soft when reaching the puller. In order to fix this, you can increase the fan speed and/or decrease the extrusion speed (giving more time for cooling) and/or decrease the temperature (in that case H1 mostly). In all three cases, the filament should be more solid when reaching the puller : it will keep its shape better.


- Sticking to the wheel : this also happens when the plastic is too hot. The ways to fix that are identical.


Did you make a datalog during the process? If you could send me this, it will give me much more insight in the process, so I might be able to give you better guidance in finding the correct settings. A datalog can be made with our free Devovision software which can be downloaded here: .


Let me know if the above information helped you to solve the issues.

Kind regards,


This post was modified 2 years ago 2 times by timo

Best regards,