printing with carbon fiber reinforced filament

[richnormand]

Could not find a previous post here about the subject from the forum search feature.

There might be some interest in this. It also mentions a response by J. Prusa.

https://hackaday.com/2024/08/07/on-carbon-fiber-types-and-their-carcinogenic-risks/

I print some special holders with carbon conductive PLA filament to use in my SEM but the situation described here seems quite different.

[thm_w]

If you need some sort of conductive filament fine, I assume you are using something like this with carbon black additive?
https://cdn.shopify.com/s/files/1/0717/9095/files/TDS__Conductive_PLA_1.0.1.pdf?1771

Hobbyists using carbon fiber filament for its physical properties is just stupid.

[richnormand]

Thanks for the link. As shown in your first link, indeed it is the ProtoPasta filament that I am using !

No, definitively not using it for strength.
As the specs sheets points out, it contains amorphous carbon black/polymer to create an electric conductive 3D print.
I use it to make non-standard sample holders for my scanning electron microscope (SEM).
The sample needs to be conductive and the sample holder also, otherwise the electron beam will create an accumulation of charge that deflects the backscattered electrons and distorts and blooms the resultant image and EDS results.

The Hackaday article I was pointing out to however are using carbon fibers and tubes to strengthen the print but, as you can see in the SEM pictures the small size and sharpness of particles could have health effects.
So, some caution might be appropriate until further studies are done with that particular type.

Cheers.

[dferyance]

Hobbyists using carbon fiber filament for its physical properties is just stupid.

There are many different kinds of material properties. Yeah PLA is damned strong. But in different scenarios a different material is better. I print some things in CF-Nylon. Not a lot, but it has it's place. I need something flexible. PLA is strong but isn't flexible, it is very brittle. PETG is flexible but not very strong. I generally print nylon in this case. However, sometimes nylon is too pliable. There are different variants of nylon filament and some flex more than others. When I need a nylon filament that can both flex and have some spring to it, but also is stiffer than normal nylon, a fiber-filled nylon works well.

I'm sure there are people using more specialized filaments than they need in different situations but that doesn't mean there aren't merits to them. The most important factor in strength is layer adhesion so this really only makes sense if you have strong layer adhesion. With careful tuning and drying my filament, I can get near-perfect layer adhesion with cf-nylon. This is better than what I've seen with other materials e.g. ABS, ASA, PETG. PLA is generally great an is the exception.