I can see strengths and limitations of of either an on-the-table or a beside-the-table 4th axis.
On-the-table would require more Z clearance which introduces rigidity problems for the Z axis, but reduces the space needed for the machine in the X or Y dimension.
Beside-the-table requires extra desk or floor space for the machine, but does not require the extra Z height. I guess my preference would be for this arrangement, but I am open to either option.
Are there control systems that can recognize if/when steps are lost and then reorient itself to a known position before it starts cutting again?
An ultimate machine would never need maintenance, or at least be self-lubricating and self-cleaning. It would keep track of hours and play in the system and let me know when and which parts need replacing.
How about an optional air drill or laser that could rotate 90 degrees to drill holes either from the top or on the sides of material...
- Randall Newcomb
10 fingers in, 10 fingers out - another good day in the shop