Okuma lathe conversion.

You might need the demo board to program them. I am not sure.

Which drives are you going to use?

timewarp wrote:

I have not figured out what I am going to use for drives. I have some vfd drives from emerson/control technologies that might work but i would need a card to put in them I think. I also have been looking at amc as they seem cheap and popular.

I assume that your motors are brushless? In that case most types of VFD won't work (CT Unidrive will, with the right setup, if that is what you have).

AMC drives with hall-sensor inputs will work with the commutation encoders.

You _can_ commutate with a normal encoder with software in LinuxCNC, but I don't really like to recommend it for an axis.

If you get the commutation sensors aligned correctly then the Mesa 8i20 with software commutation is an option.
What is the power and voltage rating of the motors?

timewarp wrote:

I picked up 3 unidrive 1402's here locally, but don't have the servo card with them, some modbus card?
There is a photo of one of the servo nameplates on page 1, other axis motor is 2kw i think.

If you can find a servo card then those are very good drives, so I would be tempted to use them.

Ask CT what you need to run your servos.

Otherwise, the Mesa 8i20 can handle 2.2kW @ 300V or so.
The Pico drives are rated 20A / 160V and may also be an option: www.pico-systems.com/acservo.html (depending on voltage)

AMC would be a good choice if the price was right.

One other (rather eccentric) option might be to fit Resolvers. Resolvers are great and can be used for commutation, and there are some on eBay with a nice big hole.
www.ebay.com/itm/New-Tamagawa-BRX-Smarts...4:g:CowAAOxyXTRR~Iy7
www.tamagawa-seiki.com/pdf/download/1507n15ej.pdf
(12.7mm bore)
The CUI encoder documents mentioned that resolvers are excellent but very expensive, those on eBay probably list at $500 normally.

timewarp wrote:

Hi Andy, Can you please have a look at this document and tell me which encoder output signal I should pick (page 3)
I am thinking 312c or 312d?
media.digikey.com/pdf/Data%20Sheets/CUI%...ds%20PDFs/AMT31.pdfl

That is going to depend on what goes at the other end of the encoder. So, you need to look at the requirements of the encoder counting hardware and the motor drive (if the commutation signals are being wired direct to the drive)

timewarp wrote:

If I can get the amt encoder to play with the 8i20 drive I will go that route I think.

That should be fairly straightforward.

As an aside, How do the tamagawa resolvers mount to the shaft?

Some have a small setscrew (page 12) or you clamp them against a shoulder (page 11) with an axial screw.

When I recently removed the encoder from a motor to fit a resolver I used the second approach, but I was already machining the motor shaft to shorten the motor.