Re: Drill-Mill CNC conversion design.

CADMAN:

Good models. I'm not sure I understand all the parts and pieces
though. Anyway here are a few thoughs for what they are worth.

I didn't see a method for tensioning the belts. I think this is needed, to
get the right tension and thus minimize backlash.

Will the posts which mount the motor plate to the bearing plate be stiff
enough? I'd make these of large diameter for back and forth stability or
build spacers which connect two or three holes (kinda triangulate the
posts). I'd worry a little about flex and also any resulting vibration.

It would be cool if you can sneak the Z-axis into the casting. Others have
mentioned the bearing set up on this. However, if you separate the
bearings top and bottom it may be difficult to allign these and the spindle
clamp. Doable though.

Is the X-axis thrust taken in your bearings or on the other end? My mill
has the thrust taken at the left end.

I can't see how you are mounting the pulleys. I've decided to use a tapper
lock (Fenner transtorque) to avoid any backlash in keyways and problems
with loosening set screws.

I don't know if this is applicable, I can't see your mill set-up well. On
mine I've decided to reverse the Y-axis motor and move it under the
knee. On yours this would put the motor under the table. But I'm keeping
the handwheels and thought the motor sticking out would get in the
way. Just a thought.

All in all it looks great. Please keep us updated on progress. Thanks.

Hugh Currin
Klamath Falls, OR

At 03:35 PM 5/30/01 +0000, CADMAN wrote:

>Try http://24.12.163.105/cnc/ballscrew.htm