Messages

21

General Mach Discussion / Re: Advanced Spindle Control

« on: January 29, 2010, 06:41:33 PM »

Hood,

So I would still need the 1 per rev signal for standard lathe operations? The encoder would only be useful for rigid taping etc. after swapping the axis.

First I've got to get the rest of the ghosts out of the machine.

Do you know a good Exorcist specializing in electronics? 

Monty

22

General Mach Discussion / Advanced Spindle Control

« on: January 29, 2010, 05:56:35 PM »

OK here is the issue.

I would really like to be able to have spindle positioning on my lathe. The problem is the spindle drive needs an add on card to do that and they are basically not available anymore.

It will however take a +/-10V analog signal for direction and speed.

Is there some type of card to convert step and direction to analog 10V that would allow me to put an encoder on the spindle and drive it like another axis? If so would this still work in typical turn applications. How would you get around the spindle sensing issues for threading?

Monty

23

Show"N"Tell ( Your Machines) / Re: My Big Project am I crazy

« on: January 29, 2010, 05:48:39 PM »

I think you could handle the multiple spindles with tool offsets. You might have to write a macro to turn on the proper one. Or you could use a PLC for that part.

I wouldn't say you are crazy...just ambitious. 

Monty

24

Show"N"Tell ( Your Machines) / Re: 1987 Bridgeport Production Center Interact 412 to Mach3 Conversion

« on: January 29, 2010, 05:29:55 PM »

JH,

Nice looking project. What are you going to use for break out and machine/computer interface?

Monty

25

Show"N"Tell ( Your Machines) / Re: My new project

« on: January 29, 2010, 10:20:27 AM »

Daniel,

Yep tried it. It doesn't help and I can't set it very high without mach missing some of the position strobes on the turret encoder.

I think I have found the problem. I have to do some more testing to make sure.

Monty

26

Show"N"Tell ( Your Machines) / Re: My new project

« on: January 28, 2010, 03:53:08 PM »

Thanks JH,

Basically what happens is the thing is rock solid. Then it will randomly have either an e-stop or limit switch trip. Once this starts up It usually doesn't calm down until I turn the machine off for a while. This doesn't always work and sometimes it's still flaky when I start it back up dead cold. Once the problem starts, I push the reset and it immediately trips. The DRO for spindle RPM starts jumping around also. So basically all the inputs start going haywire. If I then disconnect the spindle speed sensor from the board the BOB really starts going haywire with LED's and relays clicking away like Morse Code.

I've been through the whole machine. I've basically got it isolated to the breakout board. I can disconnect all the external wiring from the BOB to my machine except the power, and replace the E-stop and Limit SW with a jumper but the problem is still there. Even with all the 3 phase stuff completely disconnected from the wall. So it's not noisy wiring or a ground loop.

If I disconnect the printer cable at the BOB the problem goes away. I have also made a new printer cable and still have the problem. I really think it is a problem in the BOB.

I ALWAYS shield things and ground at one end. Also use a single point ground. Put snubbers on all the AC coils and diodes on the DC ones. Also run all AC lines separate from DC. I also try to separate all signal lines from stepper motor lines, but I couldn't do that to the turret. They are both shielded and routed in a shielded conduit. I've learned all that the hard way.

I have wondered if the Parallel port might be bad or something, but the PC and Mach are rock solid with BOB disconnected. Problem also occurs when the machine is hot or cold. So cooling isn't the issue. The hardest thing is that it is random, so if you make a change and the problem disappears, I think HEY I GOT IT!!!. Only to have it start acting up when I'm loading stock for a project.

Ah well.....keeps me off the streets.

Monty

27

Show"N"Tell ( Your Machines) / Re: My new project

« on: January 27, 2010, 07:29:13 PM »

JH,

Nice looking lathe. I'd definitely get familiar with modbus and PLC's for that one. I'm starting to wish I had used a PLC and modbus with a galil card and AC servos. I keep having a flaky random problem with some kind of noise or cold solder joint somewhere. It's driving me crazy. Impossible to track down random problems. Just about the time I get ready to make some real parts or get comfortable with it WHAM!! flaky problem returns.

Anyway, during one of it's lucid moments it managed to demonstrate the tool changer, tool table, and flood coolant today:

http://www.youtube.com/watch?v=7AQGT7AnlD4&feature=player_embedded

Monty

28

*****VIDEOS***** / Re: EmcoTurn140 test cut

« on: January 27, 2010, 07:19:32 PM »

More testing.

http://www.youtube.com/watch?v=7AQGT7AnlD4&feature=player_embedded

Monty

29

Show"N"Tell ( Your Machines) / Re: My new project

« on: January 25, 2010, 06:36:30 PM »

Thanks Brett, JH,

Spent the day working on the flood coolant system. It's sort of a temporary thing, but it will get me started. Had to track down all the leaks and made a big mess all over the floor. The bottom of the chip tray was not sealed because the original sump was a huge thing that fit under the whole lathe. Unfortunately it was missing when I bought the machine. So I spent the day caulking up the leaks with this stuff called tripolymer sealant. Works great but stinks to high heaven and drove me out of the shop. Too cold to keep the windows open and now I've got to wait for it to dry 

I had hoped to cut some "real" parts today, but Oh-well.

JH- I checked out your web site. Nice looking shop and cool bikes. Looking at the stuff a lot of you guys are doing keeps me very humble.

Monty

30

Show"N"Tell ( Your Machines) / Re: My new project

« on: January 23, 2010, 09:31:09 PM »

I finally got to make some chips today.

Here is a video of the first cut:

http://www.youtube.com/watch?v=pYYkp1wkSBY

Attached is a picture of the finished cut. My finish pass was too big. Should have been 5 thou not 10, but not too bad for a first try.

now to make some real parts!

Monty