Originally Posted by
Haitham
Hello all
Iam planning to build a 5 axis cnc for making 3d sculptures in wax or foam. I need a very very accurate machine that can get me very fine details and very smooth surface finish. I am planning to make it 150 cm X axis, 150cm Y axis and 125 cm Z axis. I ned to know which is better to get me the best results, ballscrew, precison rack pinion or belt drive.
Thanks
For what it is worth if I was building such a machine I would go with ball screws. Remeber this is my opinion.
I would also consider a moving table in the x axis so the tall z could be rigidly mounted to the supporting structure of the machine and would allow for a very wide stance. Since you are going to need 125 cm/50" I would consider having the uprights either be very wide monolithic pieces of say aluminum or use braces that approach 45 degrees as this will give a very wide stance.
If you use 150 mm/60" as the base of the uprights, this will give a 33 degree angle which should be rigid enough.
The other consideration is what type of accuracy you are looking for?
+-.010 should be doable, +-.001 is going to be expensive and anything less will most likely be out of reach for the average do it yourself guy.
Mike
Warning: DIY CNC may cause extreme hair loss due to you pulling your hair out.