Bridgeport speed control w CNC 10

[cncsnw]

TL;DR: You have a one-off custom installation, and no one knows how it works except the person who built it.

[drhodes4601]

Lol! It is starting to seem that way. Just my luck, of course.
I am considering another custom installation that involves 3 buttons and a DC power source...

[drhodes4601]

Having to work evening shift for a few days, but when I get home in the middle of the night I will see what I can find out about your questions.

Since aux 1 and 2 are programmed into the PLC and is connected to a M15SPRLY board, shouldn't we be able to disconnect the DL05 and just use the M15SPRLY to activate the solenoids manually? The auto speed control seems nice, but this is a 40 year old machine it's on.

[cncsnw]

Yes, you should be able to use the M15SPRLY boards to switch DC directly to the solenoids. That would make it much more straightforward.

[drhodes4601]

Got the wiring diagram from Centroid today. Looks like a speed control PLC came from them. Maybe it failed?

[drhodes4601]

Ever heard the phrase "walk of shame"? Well, this is the "post of shame". Years ago I knew an old mechanic. He said the best mechanic he ever knew, after getting a car to work on, would get a cup of coffee. Sit down and drink it while thinking about what the most simple cause of the problem could be. Because most times it was something simple causing the problem.

So tonight I was checking to see what kind of plug the com port on the PLC had, when I saw a switch. It had 3 positions, RUN, TERM, and STOP. The switch was in the TERM position. Switched it to RUN, and guess what? The spindle brake, Aux 1 speed up, and Aux 2 slow down suddenly all work. It is not trying to do any auto speed control from the CNC program, but still works.

My bad, should have followed the old mechanics technique. Now all that said, I am going to post the PLC program when I get the cable to connect it to my PC to see if there was any speed control attempted with the PLC. Cause PLC programming is still over my head.

Thanks to everyone who has gone out of their way to help get it running!
Danny

[drhodes4601]

So I got my cable to connect to the PLC today. I know about 0% of how programming them works, but looking at this diagram, it looks like it activates the speed up solenoid, slow down solenoid, and spindle brake. And nothing else. Am I correct?

[cncsnw]

You are correct. PLC programs don't get much simpler than that.

No doubt someone had ambitious plans to do programmable spindle speed with analog signals, but never followed through.

[cnckeith]

i would gut the air motor, solenoids, conical transmission, PLC direct and replace the whole lot with a good VFD and belt and pulley connection to the spindle motor, it is a project...but, then you would have programmable spindle speed and eliminate a ton of old stuff to go wrong.

[tblough]

+1 to this. I removed the variable speed drive from my Bridgeport clone and replaced it with a Baldor Inverter motor rated 6000 rpm, an ABB sensorless vector drive, and a micro v-belt.

I've been extremely happy with the full CNC control. I have more than enough torque even when running at 200rpm in high gear, and the micro v-belt is much quieter than the old cone drive.