Centroid Community CNC Support Forum

I need some help on installing the Acorn board on a Bridgeport EzPath Lathe, I understand that the Acorn board only has one encoder output on the board, I just realized reading on the forum about the hand wheels on the lathe that they have encoders on them also, also mention on the forum was that Centroid has an extension board for 395.00, will that extension board work or what do I need to do to get the encoders to work on the hand wheels is there a cable I need and this board or can they work on the Acorn board?

currently there is no support for dual handwheels on a lathe with Acorn.
we are working on USB MPG compatibility drivers which might allow two MPG handwheels to be used.
for now, moving an axis manually with Acorn can be accomplished by the means outlined on this page.
http://www.centroidcnc.com/centroid_diy ... ntrol.html

the encoder expansion board mentioned is compatible with Oak and Allin1DC not Acorn.
Acorn will in the future allow MPG connections using the CNCPC's USB ports therefore eliminating the need for an expensive encoder expansion board.

The Allin1Dc has 6 encoder inputs and can accept dual MPG handwheels for a Lathe application. (no expansion board needed)
The Oak has two additional encoder inputs and you can use the spare axis (axis 3 and 4) encoder ports as MPG inputs (no expansion board needed with a lathe for dual handwheels.)

Thank for your help cnckeith. do you have any idea when the drivers for acorn board to use hxt mpg so i can use on the bridgeport lathe thanks. bertman1

Just to expand a little to what Keith posted above about the Oak board. The Oak has two DB9 connectors for encoders - one is usually used for the spindle and the other is a spare. Additionally, any unused motor/axis input on the Oak can also be used for an encoder input by making a custom cable. Finally, the MPG input if unused can be used as an encoder input although it does not support an index input.

Using all of these encoder inputs you can build a 2-axis servo lathe with dual handwheels, dual glass scales, and a spindle encoder with the Oak.

Tom thank you for your help. I have ordered 1 more oak from centroid so i am set the lathe two hand wheels and spindle encoder off the board and hope not to many problems. thanks tom cheers.

Bertman1,

This post has the connector part numbers you will need - Digikey stocks them:

viewtopic.php?f=20&t=883&p=4020&hilit=o ... eels#p4020

and I've attached the schematic for the cables. If your axis moves the wrong direction with the handwheel, you'll need to swap the A and B phases to invert the encoder. Centroid let's you put in a negative PPR value for the spindle to reverse the encoder direction, but you can't do that with the other encoders. The only way is to swap the phases.

I'm starting on a 1996 Bridgeport Romi EZPath AcornSix retrofit - went with that controller so that I can hopefully take advantage of the original dual handwheel MPG encoders and maybe add live tooling in the future. The original controls had already been removed when I bought the lathe, and the schematic that came with it doesn't call out the wire labels for any of the servo, spindle, or MPG encoders. X servo and spindle encoders are both Heidenhain but so old that I can't find diagrams - pictures coming in my next post. I have no idea what the z axis encoder is. Does anyone know where I can find the connector pin diagrams or wire label info?
Alternatively, is there a recommended procedure for testing the leads to figure out what's what without releasing the expensive smoke? I have a 2 channel oscope.

The DC servos are SEM MT30M4-38 and MT30F4-45. I'm planning to drive them with Gecko G320X. If that's a bad idea, I do have 2 Delta ECMA-C30807FS AC Servos (ECMAC30807FS 750W) with step/dir compatible drives leftover from another project that could be used. Thanks!

BTW, the gutted bridgeport controls came with with it. PM me if anyone has a use for the old boards

Pictures of the spindle (#1) and servo encoders (#2 & 3) attached

The ROD 426 data should be on page 59 of this document: https://www.heidenhain.us/wp-content/up ... ers_en.pdf. Be wary that the Id. Nr. does not match up with the currently produced specs and could be something different. Either need to find older documentation or reach out to the manufacturer.

This page: https://www.heidenhain.com/products/rot ... l/ero-1400 has info for the third one (ERO 1421) series. Your best bet for the one with the QR code is to scan it and hope that it links to the datasheet.

Got both motors running on G320X drives, thanks for the heidenhain links!