I found some stepper motors that have the encoders mounted on them, so I pulled them off.
One is a US Digital E2 500 CPR (upper picture), which is perfect. The bore is even .250", which is the machined shaft size on the Hardinge ballscrews.
The other encoders (bottom picture) I have are anonymous. I counted, and they look to be about 500 line.
They have 8 wires on them, so I suspect they may be differential, but I don't know for sure.
Anybody recognize these encoders (bottom/lower picture)? They came off some small Vexta, NEMA 17, 2 phase stepper motors.
Unfortunately, the bore size on the other/anonymous encoder is only .190", and I don't really want to bore it out, so I think I'll just get a shaft extender of the right size and mount it on the ballscrew shaft and mount the encoder on a riser block.
Might take a couple days to get the time to do this.
Weekends with 18 month old twins and a 3 year old are kinda chaotic :-)
More to come...