Carbon Fiber Dual Extruder Advice

Hello all,

I finally got my dual extruder working with the new door + fan and am ready to move on to something else. I want to use this 25% carbon fiber and 75% nylon filament I have and looking at the defaults in Luban it says to use a fan speed of 0%. Is this correct? Has anyone tried this? I’ve never used carbon fiber before and am looking for advice on print speeds, retraction distances, etc., especially since the dual extruder seems fickle. I would use the single extruder module but I require support structures.

Any help would be appreciated.


Nylon and PE need either very hot environment (+80°C bed) and print temps (+250°C), as i know from my filaments.
Recommened speeds are more on the slow side like 40mm/s.

But i printed only a few small functional parts lomg time ago…

I’ve printed with all variants of eSun’s Carbon fibre reinforced nylon with little trouble. I get some stringing but otherwise the suggested settings work fine. I’ve also used 3DXtech carbon reinforced PETG and it works well. As I type I have eSun’s PA12-CF in the printer and I’m impressed with the results.

My most surprising finding is the eSun white PLA+ makes an excellent support material for both nylon and PETG CF filaments. Much cheaper than soluble filaments if your model is simple enough.

I should add that even a hardened steel nozzle doesn’t last that long. I’m using a .6mm Diamond tipped nozzle.


I have been printing about 2kg of sainsmart epaCF (PA6), which supposedly is the exact same as esun epaCF so far and didnt see any wear on my 0.4 brozzl steel nozzle and no clogs so far. Fan at 0 is not mandatory, but if you turn up the fan, you will get bad layer adhesion.
Same with speed. You can print relatively fast up to 60mm/s, but layer adhesion improves if you go slower. I print most at 30mm/s
Recommend printing on a glass bed with magigoo PA, that stuff is really good.

@david3 I wanted to try epa12CF for a while now but was hesitant because the PA6 parts that I printed became very soft when wet and expanded to a degree, that dimensional accuracy is completely off.
Even though PVA supports work great in print, I cant get them off, because the parts start warping as soon as I put them in water…

PA12 is supposed to be better in that regard, whats your experience with that?

I had similar results as you with PLA supports, but native Nylon supports work equally well.

Something that I tried, that also looks promising, is Nylon with PLA (SUNLU PLA-CF) infill. Nice way to get stiffer parts with beautiful surface. The adhesion is on the weaker side, but sufficient for smaller parts. I can separate the skin and the infill when I tear a part down, but in normal use, I can see no problems.

If surface quality is your main goal, I would recommend Prusament PC-Blend CF, that stuff is remarkable, worked flawless on first try.

Extrudr xPETG CF is also a nice material that doesnt string much, and gets a deeper black than nylon and PC, those are rather dark grey.

Printing on an Artisan btw. The image is PC-Blend CF at 0.16 layerheight, still a work in progress though…
No warping with any of the mentioned materials.

Sage advice regarding speed - I just had an 8 hour print shear off about half way through. I was printing a 50mm/s so it seems it likes it slower.

Most manufacturers of carbon fibre reinforced filaments seem to suggest a .6mm nozzle (not all) but they all suggest layer heights >= .2mm. I assume that’s for strength but I’ve not tested different layer heights for strength. Like you I’ve had no issue with clogging at .16mm. I’m using an A350.

That’s a very nice finish on what I assume is a camera body.


I know, but I didnt bother get a new nozzle and had no problems with 0.4mm so far. 0.12mm layerheight works equally well, but the difference in surface quality is not really big. There is a video somewhere on youtube where some guy tested strength of different layer heights. Wasnt really a big difference as far as i remember. If there are no angled sections, 0.2 is all you ever need, but I got some sloped and angled sections, where the steps are nicer with 0.16mm layerheight

You only need a single interface layer, 2 at the most.

But then you still waste your equally expensive nylon…