Hi All, So I built my CNC machine last year and it works okay, Why I say that is that it gets bogged down a bit due to all of the weight I added. This mainly happed becase I used 4.5mm stainless steel plates for everything. And that adds like 40lbs to the machine. So this is my question. I have found someone to make me the same parts that I made in stainless before but this time in 4.5mm 3K carbon fiber. The replacement of the parts would e a simple swap in and out. The motors would run a lot better. But my question is would the 4.5mm carbon fiber be stiff enough for this kind of applicatiion. Has anyone else done something like this and had positive results ?? Thansk Steven
I would have the parts remade using aluminum. I do not think that the carbon fiber sheets could take the long term stress that they would be put under. Maybe someone else could give you a more definitive answer, mine is just a gut feeling.
Yes, I can attest to the strength of CF plate! I've made a few things from 5mm plate in our shop and it is almost un-bendable in any configuration and extremely light. As for failure modes, keep in mind that CF is a composite material and thus highly ansiotropic and is prone to catastrophic failure if overstressed. Basically meaning it doesn't fail on a gradient, it will go from 100% strength to nothing very quickly unlike metal which will typically warp an bend before breaking. (this is why CF is typically layered with multiple types of aluminum and titanium in aircraft to enhance its strengths and minimize its weaknesses.) My 2c on CF.
Here's a good video showing it, once it starts to splinter it's basically finished. last test they show kinda speaks for itself. CF is incredibly strong...up until it's not.... lol
It's light, strong, and "brittle". Goes just about straight to catastrophic like you said. There's a nice CF F1 drive shaft torsion test on YT.