First design - Few questions

[9designs]

Thanks for the encouragement, I did read and appreciate the little rant. I guess you could say I’m into engineering, apprenticeship trained and qualified, working as a mechanical engineer for the last 25+ years :)
So my gut instinct was telling pretty much want your posts have been leading to.

Anyway to try and put some fact & data to it and to defend some use of wood haha.
I compared two beams, one steel 50x50x4mm 1400 long. Constrained both ends and applied a 750N load in the middle. Deflection = 0.225mm

The same applied to a Marine Plywood 25x200mm beam. Deflection = 0.0345mm







OK the steel is the same in Z and Y.... The Ply only in Z. So perpendicular bracing required. (Ply also has lower thermal expansion and once sealed should be OK for humidity).

What would be a suitable spindle motor, single phase, from where? I can then look to see if I can adapt the mounting to take it.

OK some rendered shots of my hybrid Aluminum/Wooden wonder.... :)









Gantry assembly complete comes in at around 77Kg. The center of mass is between the spindle and the Section8 cross beam. Cutter is inboard of the gantry end plates which are 275mm wide with two HGW25HC per side.

Width between gantry is 900mm, give a cutting width little over 700mm.
Bed length is just under 1400mm. Z clearance 130mm.

I'm sure it will raise a few eyebows