Ep9: Epoxy Granite CNC Design - Filling Taig with Epoxy Granite

Ep 9: I finish with the experiments on the Taig. The Taig is filled with epoxy granite. I show the Taig fully together and discuss what I learned from it, with the intent to apply to the epoxy granite scratch built design.
*Re-upload with better editing to get rid of dead air*
I'm designing an epoxy granite CNC machine, benchtop sized. The focus on this series will be on the "why" of the CNC machine design. The CAD software I'm using is Onshape. I'm a mechanical engineer, but I don't have CNC design experience, so I'll be learning as I'm going.

[@raindeergames6104]

Good job man. I just finished filling my 6060 gantry frame. About 600lbs of epoxy went into the base and the bed

[@billsmith5166]

Cool! I don't think you need to add any metal to increase strength, but it would provide additional damping simply from the added mass. The heavier the better with one exception. If you were to move the mill, a filled column, say with lead wheel weights and epoxy, would add a LOT of stress on the bolts {and your back}. I've always wondered why the connection between the column and base aren't substantially wider and with more screws. At some point, the column would, for all practical purposes, become part of the base. Not only that, the tramming would be much more precise. Glad I found your channel!

[@nickp4793]

Yeah, I'm trying to balance weight with performance. I actually just moved this Taig mill from my dayjob to my apartment living room 1 month ago. The apartment I had to go up 2 flights of stairs. I ended up leaving it all assembled. It was about the limit of what I could carry up the stairs by myself.

Of all the ways I've seen it done, my choice would be 3 set screws to tram the column and channels to inject epoxy between surfaces to perfect contact because I believe it may be important for vibrations.

[@nickp4793]

Thanks. What would you do for clamping? Would you use 4 bolts? Or 3, one on top of each leveling screw? I have to figure out how much the epoxy shrinks once it cures. I think the clamp screws might need to be tightened after curing, but I'm uncertain.

[@raindeergames6104]

I also like the idea of adjustment set screws and then injecting epoxy.

[@tugrulcagr7640]

@@nickp4793 Hi Nick did you watch Stefan Gotteswinter's video "Tramming a milling machine with epoxy" ? He uses a speciality epoxy.

[@nickp4793]

@@tugrulcagr7640 Yes I did, and I read all 400 or so comments on it! ha ha. The diamond paste he used has a distributor close to me, but I have not bought any yet.

[@paulxander5970]

yum...