Centroid Community CNC Support Forum

i am currently working on getting my acorn to control the spindle on my 7x10 lathe. planning on hooking it up the way FrancoCNC did in this Video. To fix the problem of isolation i am planning on buying a KBSI_240D. Theoretically i should be OK for on/off and speed. So now for my questions.

1-Do i need to control the ac power to the lathe with a relay so the spindle is totally off?
2-Using spindle fwd and reverse outputs how would be best to hook those up to relays?
3-If using relays to control fwd and reverse is there a way to set delays on direction switch to allow the spindle to stop correctly

Anyone??

As an electrician, I do not recommend ommitting the safety ground. EVER.

If the controlled motor is a standard DC brush motor, then use the KBIC schematic provided by Centroid in the schematic package. It requires the use of the KB Electronics Signal Isolator. It has been tested.

Hacking into an existing motor control requires you to know what you are doing and weigh the risk. (Both to yourself and the control components). Be aware if you choose to experiment with your Acorn and damage it, because you didn't follow Centroid provided example diagrams, it is likely not to be repaired, or replaced.

Because Acorn can not currently provide a 0 to -10vdc analog output, you will not be able to reverse the spindle in the traditional sense.(currently Acorn only provides a 0 to +10vdc analog signal typically required of a VFD)

If your lathe spindle is threaded, and you are using a Chuck instead of a collet, it's typically not good practice to reverse the spindle as it can unscrew the Chuck. Especially if you turn from forward to reverse as in tapping. The inertia of the chuck can unscrew it from the spindle.

I don't think anyone is going to recommend doing something unconventional, because of the risk of damage to the machine, control or yourself. In my opinion, anything else is experimentation.

Do it right, be safe, and have fun.
Marty

galyion wrote: ↑Wed Mar 21, 2018 11:18 pm i am currently working on getting my acorn to control the spindle on my 7x10 lathe. planning on hooking it up the way FrancoCNC did in this Video. To fix the problem of isolation i am planning on buying a KBSI_240D. Theoretically i should be OK for on/off and speed. So now for my questions.

1-Do i need to control the ac power to the lathe with a relay so the spindle is totally off?
2-Using spindle fwd and reverse outputs how would be best to hook those up to relays?
3-If using relays to control fwd and reverse is there a way to set delays on direction switch to allow the spindle to stop correctly

Hello, here's how I control the spindles on an ORAC lathe & a (under construction) mill. Both have Acorns, KBCC-125R (R for reverse) SCR speed controllers, KBSI-240D isolators and PM DC motors. They both have a manual/automatic toggle switch & a KB 5K potentiometer when manual speed control is desired. In automatic, Acorn's 0-10V analog controls the desired speed in forward & reverse very accurately.

The KBC-125R has all relays, braking resistor, heat sink & whatever elecktrickery is needed to do what you want. They know their stuff! You'll have to discard your Chinese speed control but you could sell it on ebay. Both the KB units are available on ebay used for very little money. That's my 2 cents worth.

Here's link to what I did: viewtopic.php?f=60&t=1594&p=10067&hilit=kbcc#p10067

The KBCC-125R is something i didnt see before. might have to go that way.

DICKEYBIRD wrote: ↑Fri Mar 23, 2018 6:47 pm

galyion wrote: ↑Wed Mar 21, 2018 11:18 pm i am currently working on getting my acorn to control the spindle on my 7x10 lathe. planning on hooking it up the way FrancoCNC did in this Video. To fix the problem of isolation i am planning on buying a KBSI_240D. Theoretically i should be OK for on/off and speed. So now for my questions.

1-Do i need to control the ac power to the lathe with a relay so the spindle is totally off?
2-Using spindle fwd and reverse outputs how would be best to hook those up to relays?
3-If using relays to control fwd and reverse is there a way to set delays on direction switch to allow the spindle to stop correctly

Hello, here's how I control the spindles on an ORAC lathe & a (under construction) mill. Both have Acorns, KBCC-125R (R for reverse) SCR speed controllers, KBSI-240D isolators and PM DC motors. They both have a manual/automatic toggle switch & a KB 5K potentiometer when manual speed control is desired. In automatic, Acorn's 0-10V analog controls the desired speed in forward & reverse very accurately.

The KBC-125R has all relays, braking resistor, heat sink & whatever elecktrickery is needed to do what you want. They know their stuff! You'll have to discard your Chinese speed control but you could sell it on ebay. Both the KB units are available on ebay used for very little money. That's my 2 cents worth.

Here's link to what I did: viewtopic.php?f=60&t=1594&p=10067&hilit=kbcc#p10067

Milton, so with that drive you can "plug" reverse ok?
I didn't see where they had a signal isolator for the drive itself like the KBIC series, but likely because of its design it can't be fitted, so that's why you used the KBSI-240D?

I think I did see you mention this before but didn't fully understand that it does reverse.
Marty

martyscncgarage wrote: ↑Fri Mar 23, 2018 9:38 pm Milton, so with that drive you can "plug" reverse ok?

Sure can Marty. I can start up the spindle at max speed then click the spindle direction buttons alternately as many times as I want. The spindle starts, accelerates to max speed, brakes smoothly to a stop, relay on the KBCC clacks, spins up to max speed in the opposite direction, brakes to a stop, relay clacks, spindle spins up again in the other direction ad nauseum 'til I get tired of playing with it. No muss, no fuss no smoke. The KBCC-125R has a KB APRM-3 "Fast Anti-Plug Reversing Module" onboard with a KBMM SCR speed controller, braking resistor and heat sink. It's fairly large but well worth making a place for it. The KB engineers completely eliminated my worry & confusion about reversing while the spindle is still moving.

When I first did the ORAC conversion to Mach3 a few years ago, everyone cautioned me about the bad things that would happen if I didn't get all the relays & circuits exactly right to have spindle reversing with a standard SCR type KB controller. Having said all that, KB's later PWM controllers may handle the reversing issue even easier. I don't know that for sure, seems like I remember reading it somewhere.

DICKEYBIRD wrote: ↑Fri Mar 23, 2018 11:09 pm

martyscncgarage wrote: ↑Fri Mar 23, 2018 9:38 pm Milton, so with that drive you can "plug" reverse ok?

Sure can Marty. I can start up the spindle at max speed then click the spindle direction buttons alternately as many times as I want. The spindle starts, accelerates to max speed, brakes smoothly to a stop, relay on the KBCC clacks, spins up to max speed in the opposite direction, brakes to a stop, relay clacks, spindle spins up again in the other direction ad nauseum 'til I get tired of playing with it. No muss, no fuss no smoke. The KBCC-125R has a KB APRM-3 "Fast Anti-Plug Reversing Module" onboard with a KBMM SCR speed controller, braking resistor and heat sink. It's fairly large but well worth making a place for it. The KB engineers completely eliminated my worry & confusion about reversing while the spindle is still moving.

When I first did the ORAC conversion to Mach3 a few years ago, everyone cautioned me about the bad things that would happen if I didn't get all the relays & circuits exactly right to have spindle reversing with a standard SCR type KB controller. Having said all that, KB's later PWM controllers may handle the reversing issue even easier. I don't know that for sure, seems like I remember reading it somewhere.

Awesome, good to know Milton.
You finish that paying work so you can get back on those machines?

martyscncgarage wrote: ↑Fri Mar 23, 2018 11:13 pmYou finish that paying work so you can get back on those machines?

I was so ready to do exactly that this very weekend but alas, my new (to me) Nissan Frontier pick-up's gotta have a front u-joint replaced, the freakin' bushes in the front of the house are are 8 feet tall, the lawn's turning green, there's all manner of spring projects around the house & SWMBO's honey-do list is a mile long!

thanks for the help guys. i will be picking up the kbc-125r. Dickeybird would you share how you set it up in wizard?