[Thunderhorse]

Hi everyone,

I'm planning to build a double sided 3 axis CNC machine capable of doubled sided incremental sheet forming.

Has anyone built anything like this before?
Is it best to use guide rods/ dovetail slides/ rollers?
How easy will the control system be? Each lead screw on each axis will move simultaneously.

Thanks!

[awerby]

I have to confess I've never heard of this before, but I found a few articles on it: A Mixed Double-Sided Incremental Forming Toolpath Strategy for Improved Geometric Accuracy | Journal of Manufacturing Science and Engineering | ASME DC

It does seem like an interesting idea. But offhand, I'd say that unless the sheet you're planning to form was fairly thin, the forces this machine would need to withstand would vastly exceed the forces we deal with in the typical gantry routers that most of the discussion on this site revolves around. I don't recall any threads here about building anything like that. A couple of very beefy milling machines or industrial robots butted up against each other would be more like what's required to deform steel sheet of 16 gauge or more. I don't think the typical guide rods or profile rails used in DIY routers would be much use; heavy-duty dovetails in massive iron castings would be more to the point. Using rollers at the point of contact instead of simple hemispheres might help reduce the forces needed to move them laterally, but the force required to move them perpendicular to the sheet would still have to be massive, like that exerted by the ram in a hydraulic press. The control system would have to accommodate two different 3-axis toolpaths running simultaneously, and you might have to write the software to generate those paths yourself, since I don't think any available commercial software will do that. But this paper http://www.uni-obuda.hu/journal/Paniti_Somlo_53.pdf has some hints as to how that software might work. Good luck, and please write back if you get anywhere with this project.

[Thunderhorse]

Thanks for the reply Andrew, you have given me a lot to think about. You made some very interesting points and given me some ideas to work with.

Thanks a lot, I'll be sure to update you on my progress!