Bridgeport BOSS Series 1 Rigid conversion

I'm a hobbyist with a Boss Series 1 stepper machine that I've converted to servo/VFD. It's a Series 1 Rigid Ram 16" x 42" with the QC#30 spindle. Once upon a time the machine lived in a college machine shop but saw very little use due to problems with the Textron system. As a result it sat for a <long> time not running but is in spectacular condition given its age.
I ran my first project on the machine this weekend and noticed the quill got warm - the laser measured max 110* on a 98* day running 3K RPM for about ~60 minutes total on and off. It seems reasonable to expect the spindle bearing grease is dry and caked up. The spindle makes no funny noises and the machine runs quietly. No clunking or chatter. It could probably use a new VariDrive belt as this one has a bit of a lump from sitting. Turns easily by hand.
I haven't gotten the way oiling system added in yet - that is my next stop on the build - but the way oiler doesn't lubricate the spindle from what I have read. I manually lubricated everything for the one job I've run.

Assuming the bearings are still in good shape (and I suspect that they are...), should I be dropping the spindle to re-grease them before continuing? What is my most reasonable course of action?

Thanks!
-Todd

A 12°F rise in temperature @ 3K RPM is nothing to worry about. Well within the normal operating range, in fact I would expect more rise. Your bearing grease is fine.

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Originally Posted by Jim Dawson

A 12°F rise in temperature @ 3K RPM is nothing to worry about. Well within the normal operating range, in fact I would expect more rise. Your bearing grease is fine.

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:cheers: That's great to hear!
For future reference, what kind of temperature change would make you concerned?

If the spindle is getting up to maybe 135°F+ I might start getting a little concerned. I would never expect to see this at 3K, maybe at 6K, which on that machine is outside the normal operating range as I recall. Just after I had my BP clone spindle rebuilt, it did get pretty warm (uncomfortable to put your hand on) when running at high speeds. But after running for a few hours it settled down to a nice comfortable temperature at any speed. When running at 6K RPM for extended periods, my Haas spindle gets pretty warm to the touch, but I have never measured the temperature.

I have a series 1 bridgeport all wired up on a vfd. Want to know how to wire speed controll n brake so I can play with the best peed to keep it at for the vfd. How do I wire selioniods to play with the original speed controls or maybe for low torque applications??

I'm fairly new at restoration. just jumped into this. Just got selanoid n coolant motor left to figure out. Using breakout board n mach3 program on this old bridgeport series 1 cnc mill

Any tips help on how to hook up appreciated thanks for your responses