Fanuc red cap motor usage questions

[jsheerin]

I'm working on upgrading my router. It's currently a somewhat standard diy machine - ~2HP wood router, skate bearings, acme screws, steppers, Gecko G540, etc. I'm working on revamping it as a much faster, more robust machine - large ball screws for dual z axis, one carrying a drill head, the other a 3.7kW Chinese spindle with VFD. THK rails for all axes with way covers. Rack and pinion drive for the X and Y axes. Servo motors for all axes. Which brings me to my question.

I have been working on figuring out what size motors I need to get the acceleration and speeds I'd like and I've been trying to strike a balance between price and performance. I think I can get away with Gecko drives and the N34 size brushed DC servo motor that Keling sells for my X axis (dual motors) and for my z axes due to the lower weight. However I'm having problems with the Y axis. The moving mass is high enough that a single one of the Keling motors will be the limiting factor in the machine's performance. So I've been looking at used servo motors on ebay. The Fanuc red cap AC servo motors seem plentiful and cheap for the torque available. However I'm having a hard time finding any data sheets. Fanuc's website seems fairly worthless. I've done some searching here and found that the encoders that come on these motors may not be suitable for using with commonly available motor drives but other than that have not found much. I was looking at using these with the Granite Devices drive specifically.

Does anyone know where I can find data sheets or part number keys for the Fanuc motors so I can better evaluate what I'm looking at on ebay?

Could I (relatively easily) install a new encoder on one of these motors if the included one doesn't work with my drive?

Any other advice for a newbie to servos?

Thanks,
John

[Al_The_Man]

If you look through past posts of mine and others, I have converted these motors to Renco for BLDC use, also Jon Elson makes a convertor board which makes use of the exsisting encoder.
If you PM me a email address I can send the Fanuc motor data.
Al.