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Encoder for Acorn lathe project

Posted: Fri Aug 13, 2021 11:08 am
by bportserII
(Disregard the screen name, I also have a big Bridgeport II with an antique Centroid control {would like to find a quill gearbox to change the z axis to the quill instead of the air assisted knee})

Name is Bill, 73 year old retired, Vietnam, machinist, Aircraft mechanic-Inspector rebuild antique tube and fabric airplanes, Hotroder, BA-Journalism

So. I purchased the pro package and installed it. tried to get my encoder working but no luck. Still on "bench" (coffee table in den, it is close to 100 here in central Texas)

Encoder is a:
Sumtak "optcoder"
Type:LBJ-302-2000
DC 5V 80mA
0011-1141 2000p/r

How I wired it:

Encoder Acorn
wht 5v pin 9
blk 0v pin 2
red A pin 7
grn B pin 8
ylw Z pin 6
pnk 0v
blu 0v
orn 0v

tried it this way and nothing. Did go to the wizard and setup for encoder. then tried all different combinations of the pnk, blu and orn to pins 3, 4 and 5 to see if It also had to have the "-", still no encoder.

Any suggestions?

P/S Marty's videos on you tube were fantastic for getting me up and running. Had all kinds of "gremlins" and was able to work them out.

Thanks,
Bill

Re: Encoder for Acorn lathe project

Posted: Fri Aug 13, 2021 12:06 pm
by tblough
Acorn needs a differential line driver quadrature encoder. A TTL output encoder, like yours will not work with any of the Centroid products.

Re: Encoder for Acorn lathe project

Posted: Fri Aug 13, 2021 12:50 pm
by bportserII
Any links to one on ebay? I'm a cheap so---

Re: Encoder for Acorn lathe project

Posted: Fri Aug 13, 2021 12:54 pm
by AdamCNC
I used one just like this.
Works fine
https://www.ebay.com/itm/333709462341

Re: Encoder for Acorn lathe project

Posted: Fri Aug 13, 2021 3:53 pm
by eng199
That model has open collector outputs (it isn't the right kind). The line driver model is E6B2-CWZ1X.
The output frequency is only 100khz on those, so be aware of the maximum frequency as described in note 3 in the datasheet.

https://www.ia.omron.com/data_pdf/cat/e ... csm491.pdf

Re: Encoder for Acorn lathe project

Posted: Mon Aug 16, 2021 10:38 am
by martyscncgarage
bportserII wrote: Fri Aug 13, 2021 12:50 pm Any links to one on ebay? I'm a cheap so---
Piece of advice, cheap and CNC don't play well together.
Those Omron encoders I believe are knock offs of genuine Omron. That said, many have had success with them. They are not designed to take a radial force, so avoid mounting a pulley to it and driving it with a belt. If you must use it, couple it to a jackshaft arrangement.

Re: Encoder for Acorn lathe project

Posted: Tue Aug 17, 2021 1:03 pm
by bportserII
Marty,
Thanks for your reply. I do recall seeing your video on those encoders, in fact I binge watched all your videos before I made a decision to purchase the Acorn over a Mach 3. I had used a Mach 3 to build a plasma table but I specifically wanted spindle encoder feedback on my lathe. Your videos have been invaluable on this project.

Re: Encoder for Acorn lathe project

Posted: Tue Aug 17, 2021 1:19 pm
by martyscncgarage
bportserII wrote: Tue Aug 17, 2021 1:03 pm Marty,
Thanks for your reply. I do recall seeing your video on those encoders, in fact I binge watched all your videos before I made a decision to purchase the Acorn over a Mach 3. I had used a Mach 3 to build a plasma table but I specifically wanted spindle encoder feedback on my lathe. Your videos have been invaluable on this project.
Glad they helped!
Marty