Re: Z axis drive

--- In CAD_CAM_EDM_DRO@yahoogroups.com, R Rogers <rogersmach@y...>
wrote:

>
> Both of my Bridgeports drive the knee for Z axis and they are in

excess of 1000 pounds (knee, table, saddle, ballscrews, 2 servos, 2
mounts and vise). Getting 60 ipm Z rapids on both and use no assist
whatsoever. 40 lb-in DC brush servo 2.5:1 reduction on a G320 Gecko.
I ran one job recently on one of these that consisted of 1280 .875"
reamed holes 3 inches deep in 1018 steel. Alot of pecking. The servo
would have to rest every 4 hours to cool a bit. The Gecko would've
run continually it seems. Great job Mariss..

>
> During the retrofit and setting up the electronics, I had

determined that drilling for prolonged periods would be out of the
question. I was wrong.

>
> Ron

Since there is plenty of room under the knee on a Bridgeport and the
travel isn't too far, you might benefit by sticking a good sized
(bore) pneumatic cylinder under there connected to a small tank and
regulator. Take some of the load off the leadscrew and you should get
better performance and less heating for very little cost.

Pete C.