Hi Jack & others - I use epoxy or contact cement. Contact cement has advantages, cheaper and strong. Up to you. And yes you laminate the ply yourself. You can rough the sheet down to size then laminate then finish cut and drill. Use a hard spec aluminium. Not soft stuff. Soft tempers will crush under bolt loads. About 2mm thick is a good starting thickness... Also can laminate extra bits on where local stiffness needed. Laminated metal is common in aircraft industry look up "GLARE" Peter
https://en.wikipedia.org/wiki/GLARE
Hi V0dka - As an aside and since your happy to work in plywood and since your CAD skills are very good I suggest you consider a UHPC machine. Making mdf moulds is straightforward and then you can design and build parts that are more suitable for the job. Your machine has 100's of bolts, brackets spacers, All of these can be consolidated into 2 or 3 simple parts. There are high performance grouts available that are as good as aluminium. Where your heading is a complex, inefficient structure. It can be much simpler, plus concrete & mdf is cheap.. The two vids use epoxy granite but my current costing on UHPC concrete comes out half the price of using epoxy...Peter
https://www.youtube.com/watch?v=GzBAJTgo3QU
https://www.youtube.com/watch?v=2woA1BxZ7Pg
in parallel of the machine design itself, I'm also diving into the control box design.
I'm planning to use shielded cable either inside the control box. To wire the stepper driver to the control board, I would like to use FTP cable Cat 6 : 4 twisted pairs ( EN, DIR, PULSE and ALARM). Would the cable gauge be enough ? I think so because these have hust to drive opto coupled inputs. What do you think ?
My build is going on... I've almost finished the Z Axis.
I followed the advice of @peteeng about plywood + alu sheets. I didn't any affordable 2 mm alu sheets near my home, so I chose 0.8mm steel sheets (i guled them with neopren glue) : I'm happy with the result: it seems rigid as h***.
For the threaded holes, I' used wood inserts, inserted from the back side. So I can tightened really hard with any risks of tearing off.
I've also add a steel plate (5mm thick and 45mm wide) on each side of the Z plate to increase the rigidity (screwed and glued with epoxy glue) : seems promising
Hi VO - Looking very good... Peter
May I ask what motor mount you are using for your Z axis?