Thoughts about the new carbon fiber filament from Colorfabb



Soon after @ released their flagship (in my opinion) filament, the XT-CF20, I got a few spools to test it in our coming product to be commercialized in few days from this date: a new drone racer with dynamic titling arms and mostly 3D printed with the XT-CF20.

Find info on the development on forum and in the official product web

The XT-CF20 is a blend of the Co-polyester filament called Amphora 3D from Eastman Chemical and chopped carbon fibers (not less than 20% of fibers). During the material research and testing for our drone, I got other carbon fiber blend filaments like ABS-CF and PLA-CF from other brands and I must say the XT-CF20 has the proper stiffness, toughness and manufacturability properties. The latter is especially important because unlike the XT-CF20, the ABS-CF and PLA-CF are very rigid already before processing therefore, I had serious issues when printing with them as they didn’t allow much flexing of the filament and broke several times in the middle of prints. This didn’t happen with the XT-CF20 at all, not a single time.

The extrusion of the XT-CF20 is a bit special though: first, Colorfabb recommends using stainless steel or hardened copper nozzles because the CF fibers wear the typical brass nozzles. Second, printing on nozzles with 0.5 mm bore or smaller provokes that sometimes the material gets stuck in the nozzle. Use 0.6-0.8 mm nozzles to avoid that. You can still print on 0.4-0-5 mm nozzles but you might get bad areas in the print due to some difficulties extruding.

I’ve been using the max temp recommended by Colorfabb: 260 degrees Celsius. Lower than that is supposed to work too but I didn’t get good results. Probably you can print at 250 or a bit lower in nozzles of 0.7-0.8 mm since the material has less difficulties to flow through it.

Surprisingly, the XT-CF20 has almost no warp (the part in the pictures below is the main drone plate: up to 8 mm thick part and almost 30 cm long) even at just 60 degrees bed temperature. I like it a lot, so much that I haven’t print with PLA and ABS since I got it, even for random parts, I use this filament or plain XT (which is softer than PLA and ABS but very easy to print with and good mech properties in some of my other applications).

Summarizing, I strongly recommend the XT-CF20 but first, get steel or copper nozzles of proper bore size.

For further questions do not hesitate to contact me at in Twitter or in Facebook

Happy printing!


Two more links to know how you can use this material:


Hi there !

I’m planning to upgrade my printer from a proprietary hotend that only accepts brass nozzles, to the e3d chimera in combination with stainless steel nozzles. However I heard, that stainless steel nozzles don’t transfer as much heat/time to the filament, meaning you have to print slower in order to heat the material properly.

Now to my question: How much volume/sec did you use while still getting good results ?

The formular is: layer heigth x layer width x printspeed in mm/s = volume/sec

Also I’d like to know, if the carbon fibre influences the way, that XT handles overhangs and bridges.

For example the metal blends by colorfabb (i love those, have gotten 1,5kg brass recently):

Due to the metal in the material the filament heats up quicker and cools down faster, the faster heating means that higher speed is possible and the faster cooling means, that overhangs of up to 80° (in my testing, small parts managed even 85°) will still work out, also longer bridges are possible.

Wood and bamboo don’t really influence these characteristics of the normal material, however maybe the carbon fibres do.

So the second question is: Do you see differences in printing overhangs/bridges or other specialities when comparing XT to XT CF-20 ?

Lastly I’d like to know, how the material behaves when sanding or drilling it. I’ve printed alot (5kg within 4 months) with XT Clear and it’s sandable, drillable etc. does XT CF-20 behave differently ? Also it would be nice to know how the optic changes when sanding the material.

I hope you can answer some of those questions, if not that’s no problem as I can contact the Colorfabb support, however they want to sell their product so it’s more reliable to ask independent testers, that know the everyday-struggle of 3d printing and have experience with (maybe) other materials, beside the Colorfabb ones.

Those drones look great, good luck with that !




Thanks for an awesome post, Pau! It’s great seeing the @ XT-CF20 at work :slight_smile: Cheers!


We’ve gone through 2 rolls so far and here’s what I’ve learned.


  • Love the strength
  • Surface finish and overhang/bridge support is the best of any filament I’ve ever used.
  • Prints well, with almost no warp (70º build plate and glue stick)


  • VERY ABRASIVE! If you are using brass you will be constantly re-leveling the bed due to nozzle wear. We made it through a roll with one nozzle and it took off about 0.5mm.
  • It seems a bit “stickier” than PLA or regular XT filament while printing.

I’ve been experimenting with nickel plated nozzles with some success.


Nice findings, @Molly_2, thanks for sharing! Feel free to start a new thread with these learnings, maybe share some prints to see the actual results? We really want to see more of what you guys are doing with the XT-CF20. Cheers


You’re welcome! We keep experimenting and finding good quality results.


Interesting questions Marius! In some way you might have got further than me :slight_smile:

To your questions now: first, my machine is limited by software to 15 mm/s (yes, a turtle would catch up the extruder without much effort) so I think my volumetric printing value will be of little use. I haven’t printed much with overhangs but the few horizontal, cylindric, bores I printed of 8 and 10 mm diameter, where clearly heliptical being the minor axis vertical. I’m talking of a bout 1 mm axes’ length difference (not good at all). So , I guess I had to increase the support density (used medium value) and/or print support closer to the lateral walls (1 mm distance so far). I didnt have time to test more than that.

However, abrassive postprocessing (sanding) and drilling are AWESOME. With little that you sand the part, the results is supper smooth and layers disappears. Is super nice to work with it (see pictures of my first test cube before calibrating the machine). Warping is also inexistent as you can see in that big drone plate.

And thanks for the drone comment, keep an eye on how things develop at, we launched yesterday and response is awesome!


Hi guys, I have switched to Oo-kuma CF0 which is carbon-fibers in ABS but it is the most different one I have used up to now.

Still tough with higher mechanical modulus and hardness interestingly with no brittleness!

I could advise using that



It sounds like the CF filament is definitely more durable and possibly lighter than than generic ABS or PLA. It probably won’t stack up to CF weave… but I’m still curious of the durability. Can a quantitative test be setup to compare / contrast the durability (and weight) to ABS of the same thickness? Maybe a 20x40x2.5mm plate with something like a torque wrench to gauge force required to twist / deflect? Or maybe a simple stress test with screw and weights to gauge when the the screw hole (2mm from edge) breaks…


hi, I have tried it with performanceABS and carbon-fiberABS CF0 (both from same vendor) and did a lab test in tensile and bending. both gave higher results for CF0 while the toughness was almost close (only performanceABS had a slight more elongation upon load).

most simple practical way is to hold the filaments at hand and bend it, if it breaks in 10cm diameter of wrapping than most likely your prints will. only CF0 didnot break in this condition and carried tests further where the results showed the same.



I bought a sample of 3dx TECH carbon fiber PLA. I can say I had a good experience with it.

Its very brittle, i feel like its a lot sticky that regular PLA, and its super abrasive(like 40 grit sandpaper). While make a test print it caused an insane jam about halfway up my printer. It was not very easy to get it out. Another thing I noticed is that it ruffed up the bore of my hot end. And I have a stainless steel hot end.

The only plus I would say is the it had a great matte finish after it printed. I really liked the matte finish!!

I might have to look into getting XTCF-20


if you can work with ABS than should try CF0 from oo-kuma. All the positive



@PauInkonova This is some supercool, detailed insight into the new colorfabb cf material. Sounds like a great functional material for folks with heated beds and custom larger bore/harder nozzles. Though proto-pasta cfpla is a bit less abrasive and processable at lower temps, it still wears nozzles more quickly. We’ve certainly been self critical of that fact and have recently introduced hard coated brass nozzles, starting with makerbot and flashforge style machines. Though we’d like folks to use them with proto-pasta materials, I bet they would work well for colorfabb as well ;-). Check 'em at and even use your hubperks to get a discount!


Im having trouble printing with colorfabbs carbon fiber. Its just sitting in my room now. I bought the stainless steel nozzle. .07mm and When it prints, it will print the first 2 or 3 layers and just stop extruding. If I push the filament, it will continue printing but it just has trouble extruding. Any idea?
I am using makerbot rep 2x also. I followed all your settings.


I’m printing the planes found at

Do you think the carbon filament would work in this configuration. The skin is only 1 layer thick so adhesion is key. My concern would be the noted brittleness as many parts of this aircraft are slightly flexible to the touch but don’t break or split seams in the layers with PLA.

One other thing I’ve been unable to track down on the web. Is this stuff lighter/less density due to the carbon influx? Weight savings is key for that airframe and if the carbon filament is lighter than standard PLA is would be a great advantage.


@Bob_Martz This is a super-cool link! Thanks for sharing!!! I can tell you that Proto-pasta Carbon Fiber has excellent layer adhesion, and while more stiff is also more brittle than standard PLA. The density of CF materials is not really less but something about it gives the perception of less weight (maybe the increased stiffness). Proto-pasta CF is amazingly easy to print and now only $29.99/spool so i encourage you to give it a try. You might also consider our high temp PLA which is more tough than standard PLA and when heat treated thermally out preforms ABS and PET, but with the ease of PLA printing (low temps/warp)!


Hi @TangibleCR -

First, a stainless steel nozzle is not the ideal choice for this material. Your Rep2x already requires near max temps for printing PET-like materials such as XT and the SS does not transfer heat well (or increase wear resistance that much). Instead, can I suggest instead our hard plated nozzles with better wear characteristics than and thermal performance close to the stock brass:

At $14.99, it’s the best, low-cost upgrade you can make to your printer. 0.4mm is the stock Makerbot orfice size, but increasing to 0.6mm can also further improve the reliability of your flow and printing success :

I don’t think you’ll have great luck with Makerware and a non-standard nozzle size, so I also suggest upgrading to Simplify3D. Powerful software for only $150!

Finally, if you want a more straightforward, reliable printing carbon fiber material, please give Proto-pasta a try. It was the first on the market 2 years ago and is still the best printing - and now also the most affordable at $29.99/spool:

Hoping all this feedback helps! You can use your Hub Perks discount or the code PRINTWITHPASTA for $7 off at :slight_smile:


Proto-pasta has a new Carbon Fiber Filament, HTPLA-CF. Check it out:


i love carbonfil from form futura . it’s petg or hd glass with 20% carbon fibre. prints really really well too