Thanks @Pencilfish for the suggestions. Yes, I am going to use the old nema 34 motors and the spindle on the new machine that's why I bought the bigger one to use them later. The old machine I made just in a week so I regret about the design specifications and table size but it was a great experience. Due to the lack of actual loading data I made it overspec.
I didn't expect that I will be getting so much work on CNC. Now I left my job nd started my woodworking business. Took the 1000sqft shop on rent.
Basically I am going use this machine for making hardwood and plywood doors, wood carving, acrylic and foam board cutting. Wooden/Foam Pattern making for plastic moulding(For this i need good accuracy and precision). And machine speed should be comparable to the commercial CNC Routers.
Now my biggest concerns are about the table+gantry design and drive selection (Rotating nut Ball screw/ Rack and
pinion). Just trying to contact the Hiwin ball screw suppliers if they have the rotating nut assembly which comes with outer angular contact bearings; It would save my time. For the rack and pinion Backlash is the main devil.
How is the performance of aluminium extrusion for gantry? It will be light weight. But will it give the necessary stiffness and damping against the vibrations? The aluminium profiles are very costly but there won't be another option if I am not able to find the facility to machine the steel frame. After finalizing all the basic specifications I will try to do the FEA analysis just to cross-check the design and make some optimization.
This will be a very costly project for me that's why I don't want to leave any stone unturned. So any assistance you can provide would be greatly appreciated.
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