Re: [CAD_CAM_EDM_DRO] Re: photo section broken? (works now, more on rotary axis)

Hello Rick..

Wednesday, October 22, 2003, 3:15:27 PM, you wrote:

s> The photo section seems to be working now. You did an AMAZING job
s> with that rotary 4th axis conversion! I have lots of questions, but
s> if you could just answer three it would help quite a bit:

s> 1) Where did you get the 3 jaw chuck that seems to mount so nicely
s> (or did you modify it?)

The chuck is a standard flat back 8 inch import. I just made up three tee nuts of
the correct size to fits the slots and bolted the check on.

s> 2) Why did you go with a further reduction gear on the handwheel
s> shaft? Is there quite a bit of friction? I noticed you mounted the
s> servo encoder on the handwheel shaft - great idea since belt stretch
s> would then be irrelevant.

There is some friction as I adjusted the worm as tight as practical to reduce
backlash. Also the motor is fairly high speed so the belt reduction helps a bit
there. Yes, the encoder on the shaft eliminates one source of error. It is a 1000
line (4000 count encoder) which, with the 90:1 ratio, gives a resolution of 1/1000
degree - exactly what my control wants.

s> 3) If that is a 10 inch table, is it impossible to lift without a
s> crane?

Not impossible to lift, I just don't like to strain my back. Also, since I have an
overhead gantry hoist built into the shop, I make use of it. I also use it to move
vises from the milling machines. With the hoist, you can gently set the rotary table or vise
on the mill table rather than heaving it up there and then trying to set it down
without dinging something.

s> Thanks for the pics!

You are welcome. If you need (want) any further details, feel free to contact me off
list..
s> Rick


--
Best regards,
Larry