DIY CNC Router legs

[Madclicker]

Yes, that's why I didn't use it this way. My pipe rails are supported by al channel, which is supported by hardwood. Just have to be sure you use the materials where they work the best. Anyone who has used mdf knows how weak the edges are. I just don't trust the edges as a bearing surface.

[Madclicker]

Originally Posted by Lionclaw Wouldn't this make it unsuitable for use in making tools? Edit: NM, I just read in your build log that you used hardwood up against the pipes. Would you consider baltic birch plywood (not the veneered stuff) superior for making machines? I'm considering switching to building my machines from the veneered birch to baltic birch. The cost would be significantly higher, but if there's a demand for it then I suppose it's worth it.

Andy,

As much as I like baltic birch ply for some stuff, I wouldn't use it to make torsion boxes for a cnc machine. You can't beat mdf for stability. Laminate it, and it will last.

[ViperTX]

studysession.....do you have access to a Mig welder....steel is very cheap....probably cheaper then 3 or 4 inch posts......you could also bolt the steel together....

[Lionclaw]

Originally Posted by Madclicker Andy, As much as I like baltic birch ply for some stuff, I wouldn't use it to make torsion boxes for a cnc machine. You can't beat mdf for stability. Laminate it, and it will last.

I really don't mean to argue this here (I know this thread isn't the place), and I know you've worked with wood for probably longer than I've been alive, but I really still don't see why good quality plywoods are bad for torsion boxes and other parts of the CNC.

I've had my current machine up and running for more than a year now. It isn't even sealed or painted, and I haven't had a single problem with warping, bending, or anything else related to the material.

On the other hand, my JGRO machine which was build entirely from 5/8" MDF had numerous problems, granted it might have been slightly better if I had sealed it. The MDF seemed to get softer and weaker the older it got. If I tightened a bolt into it, or pressed it hard with a clamp, it would just begin to disintigrate and flake apart.

Could you explain your position?

[studysession]

I am curious as well. I see a lot of people on this forum using either MDF or plywood or something else. I want to use what works and not warp. Thanks