Topic: Colorfabb XT-CF20 quick review
So I grabbed a sample of Colorfabb's XT-CF20 when I was placing an order from printedsolid. I was interested in trying it out since I had not really heard of this XT filament before. My understanding is that XT is a type of polyester and this has 20% carbon fiber filaments mixed in. I printed it on an E3D V6 with no nozzle fan, although if I get one setup I will see if it makes any different (it probably won't except on small layers). They say that the carbon fiber can be abrasive and wear out your nozzles faster but I only have a little sample to see how I liked it so I didn't see the need to invest in a stainless steel nozzle just yet. They are somewhat pricey, about $25 each.
I printed it at 245 C hot end and 60 C heated bed as recommended. It had absolutely no warping, stuck very well to the build plate, and no layer delamination, even when printed at with the case open. I just printed a carabiner and a box to test it out and both are very solid feeling. The density of this is given as 1.37 g/cm3 which is noticably denser than ABS at about 1.0 g/cm3. The printed parts are very rigid, but I did print fairly thick objects. The filament itself is fairly brittle prior to printing, I snapped it in one spot trying to get it onto the spool but if you buy a whole spool you won't have to worry about this.
Similar to the various filled PLA filaments available, I have to assume it is not any stronger than plain XT filament. I would really be interested in a lab test to find the tensile and comprehensive strengths of the printed parts. Based only on my visual evaluation and touching it, I feel that it might be stronger than ABS. If any has access to the lab equipment, PM me and I'll send you some part samples to destructively test.
I don't have any pictures because honestly, it looks just like a matte PLA or ABS filament in pictures. The texture of the finished part is very nice and even a lay person could probably identify it as carbon fiber based. It is a fairly expensive filament, printedsolid has it for $70 for 750 grams and keep in mind because of the density it will be less length than you are expecting. Doing a little math, you can see it comes out to 412% the cost of ABS when measured per cm3 (assume $31/ kg for octave ABS on amazon). Also factor in a new stainless steel nozzle or 2 and you are looking at about $100 to really get into printing this stuff.
You won't be disappointed in the strength, the texture is very satisfying, and it is easy to print. I might make some bezels or cases out of it and if you were into such a thing... it could make a pretty cool liberator pistol to hang on the shelf and show your buddies. If you're not worried about the cost, I would say give it a try and you will have one more material to impress your non-printing friends and family.