Bridgeport Manual to CNC conversion...

[Davek0974]

I have read some tales as its a US motor and a bit awkward to dismantle, to find bearings size i would have to strip down which risks disturbing old and fragile varnished wiring etc. Not a big issue but could end up in a trashed motor.

The extended/custom shaft makes replacements a total bugger - practically impossible to fit a new motor and re-use the Reeves vari-speed drive system as new motor shafts are far too short.

This was the reason Bridgeport motors are stupid expensive.

So, options - strip and attempt repair.

Fit a servo and dump the Reeves drive but retain back-gear ?

The budget for this job went silly a long time ago - i was not intending on replacing all the ball bearings etc and some of them are £££ so it seems now that an extra £300 or so on a 3kw servo/drive is pretty irrelevant overall.

The servo would likely be the easiest option - just a new mount plate and two pulleys, the repair on the bearings could be the cheapest option but would still leave an inferior, power-sucking drive system on what is now a damn expensive machine.

I'll work some prices out.

[Boyan Silyavski]

What about repairing it on place with graphite or bronze filled epoxy ,Moglice and others? Why dont you check if that's a possibility. It would be dirt cheap

[Davek0974]

These would be ball bearing races so not repairable in that way.

[Boyan Silyavski]

Ain't a ball screw a ball bearing that could rotate as high as 3000rpm?

[Davek0974]

I'm losing the plot here Boyan, I'm talking about the bearings inside the 1-1/2Hp spindle drive motor are buggered. ;)

[Davek0974]

Drop-plates for X & Y servo motors - 10mm, 12mm, 15mm thick ally??

[m_c]

Drop-plates for X & Y servo motors - 10mm, 12mm, 15mm thick ally??

Thicker will be better, but it will depend on servo shaft length/pulley thickness as to what's practical. Some form of box section would be better/stiffer.

Regarding the motor bearings, unless the motor has some odd wiring/end cap configuration and/or you damage the windings trying to lever the end caps off, stripping it and replacing the bearings shouldn't be a problem.

[Boyan Silyavski]

I'm losing the plot here Boyan, I'm talking about the bearings inside the 1-1/2Hp spindle drive motor are buggered. ;)

I was saying if it works for removing ball screw backslash and the ball screw is in fact a more complex ball bearing , its worth a try at the cheap price of it. How fast this motor moves? 1200rpm? Same as ball screw.


I see as a better idea changing to cheap Dc motor or better servo motor. And why not a cheap modern normal motor , disassemble, weld some shaft and machine it on place. That would be super simple. And a bracket adaptor

[Davek0974]

I'm going to have a go at dismantling i think, try that first.

A 2.0kw AC servo would be best but a toss-up between money and easy-fit;)