Hi all-
I am in need of advice about my MHP mill I purchased. It uses the Hydropath III controller. When I got it home and connected the power and the air, the machine came to life fairly easy. I was worried because it had a rough ride on my trailer for 100 miles or so.
After playing with it for a few days and finally figuring out most of the buttons, and learning how to do a tool change something changed. I started to get following errors on the x axis. I have a complete set of manuals for the machine, but there is not a lot of information about the “Following Error”. If I jog the machine really easy, then I can make the x axis move, but any faster and it faults out. During the few days playing with it, I cut a 2 inch hole in ½ plate, and by using calipers it is 2 inches. There no bumps in the cut when the axis changes direction. I did not have a chance to do any more tests on run out or backlash before the problems started.
Here is what I know about the machine-- It has a 10 HP spindle, with a pneumatic hi/low changing gearbox (50 to 5000 RPM). It has a 22 tool changer that uses BT 40 collets. It has an automatic oiler. It has a Toshiba variable frequency drive, it has some way to control the location of the spindle orientation because the spindle stops at the same position every time. The servos are 94 volts DC ( I think) and use resolvers. The z axis also has a brake on the axis.
I started to do some simples troubleshooting on the x axis tonight, and here is what I found. With the servo disconnected from the ball screw, the servo is still getting errors, and is also jerky. The ball screw appears to be in good shape, and the ways are in great shape. They are boxed ways if that matters.
I am planning on swapping the x and y servo driver just to see if the following errors follow the drive.
Now for the questions---
Should I continue trying to fix the x axis, or plan on starting swapping the electronics out and re building the mill?
I have successfully built a 6 x 12 cnc flame table, and the hardest part for me was figuring out what electronics to use. After swapping parts and have problems, I ended up using granite devices servo drives, US digital encoders, the BOB from candcnc. I also tried the smoothstepper (which I still have) and the c23 BOB (still have this too) from cnc4pc. Power supplies from Jon at Antek.
So what should I buy? I have been reading up about Ajax, and the DSPMC controllers. I would like to stay with the granite devices servo drive. The only reason is that I can order 1 extra drive and use it on either machine. I would also like to use and industrial PLC. I work with AB, Mitsubishi, Fanuc, Motoman, Toyopuc (Toyoda) and a few others at my day job, so I am very familiar with PLC controllers and the Ladder Logic.
I am planning on spending between 2000-3000, to get it running.
Any and all suggestions are welcome.
Steve