Thanks!
I believe the machine is from the early 1940's, it didn't have a motor when we recieved it, but I am pretty sure it was electric. The machine came to us from a shipyard (the original owner) and was exclusively used for straightening prop shafts and had been replaced by another machine many years before. Other than a little clean-up it was ready ready for use... its amazing how excellent old fabrication is.
The servos are Panasonic 750W (1 H.P.) 3P 230V units with matching drivers. I am using Parker 50:1 gear boxes on both axis. Because most of the cuts on this machine are slow (20 R.P.M. low gear and about 164 on high gear) and deep (we regularly did 15mm cuts manually before the conversion), we decided to add the 50:1 gearboxes to increase the feed torque at the low feed rates required (approx. 15mm/min low gear and up to 40mm/min in high gear). So far it looks like that was a good idea, the only draw back is that my max shuttle speed is roughly 25 cm/min on X and 50 cm/min on Z. But even at that speeds its WORLDS better than the 5 minutes it would take to shuttle the saddle BY-HAND from one end to the other!
The ballscrews are .75" diam/5mm pitch on X and 2.5" diam/10mm pitch on Y.
The timing belt and pulleys were a last minute thing, my father was concerned that having the X axis servo and gear box straight out from the saddle would risk it being ripped out by a careless forklift operator, falling part etc.
Hood, you are certainly right about the chatter being a pain, but its not from the saddle flexing, its from the play on the ways when the X axis out past the Z ways, the way guides need to be very well adjusted for play. It doesn't happen very often, but when you start to see chatter (see pic) its almost always because the X or Z way guide needs to be tightened. We also fabbed the tool post and holder ourselves because the original one wasn't sturdy enough for the wheels (another thing that caused chatter). I'll post a pic of the original tool post in the afternoon.
Frank
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