Experiences with PETG-CF  

Experiences with PETG-CF

I'm interested in sharing experiences with using PETG-CF. I just started using the Prusament version of this material. I am using a 0.4mm obxidian nozzle.

Observations so far:

• printing with it is very easy. Bed adhesion is about the same as PETG using the MK4 profile provided by Prusa.
• the surface texture is quite rough. I read a description of another PETG-CF giving little hairs like peach fuzz, and what I get is not as extreme as that. However, it is too rough for mechanical parts without post-processing.
• it sands down really easily, and then you get a super smooth surface. Use a dust mask, of course! It's also very easy to trim brim etc off with a scalpel.
• it seems to print a little larger than PLA. I have one part (an axle with a gear that slides along it) which perfectly dimensioned with printed with PLA, but has to be reduced by in size by about 4% with PETG-CF. This is based both on the fit of the parts and from measuring them. The surface roughness accounts for some, but not all of this. Maybe reducing the extrusion multiplier would be another way of dealing with it.
• the main reason for using it over PLA was to reduce bowing of the shaft under load, and it definitely is stiffer than PLA.