I own a sweet 1996 Bridgeport powerpath 15 lathe with DX-32 control. I hated the control when i 1st bought it but i learned to like it as time went on. Its not a mazak but it does have it pluses. The problem with this machine and just about every other aging piece of cnc equipment is the cost of control parts repair. If its Legacy you are going to pay though the nose for repair. As many of you are, I am a hobby/garage shop guy so huge repair bill are avoided as much as possible. I know by retrofitting just the servo system i am not replacing everything in the control but those are the most expensive parts to fix. The problem with having drives repaired is you are NOT getting a new drive for the $1400-$2000 they want to fix it. You are getting a drive that has had its weak link fixed. The rest of what they didnt replace is still 20 years old....they cycle continues. servos in this machine are $2200 each for a rebuild and the drives are $1400 each to rebuild. Thats $7200 to repair those 4 components. I bought Brand new Yaskawa sigma 5 servos and drives with the same ratings/specs as the old ones with the cables for $2300 shipped. You cannot just plug these into the machine and go but its really wasn't that hard to figure out.
Its possible to remove the old servo system and wires, without cutting even 1 wire! I took really good notes and pictures so just incase this didnt work i go back to the way it was.
1. 1st step was to remove old drives and cables. taking note how it was hooked up.
2. make panel to cover the holes in the control panel where old yaskawa CACR-SR drives once lived.
3. Mount new sigma 5 drives to panel
4. Remove old servos and install new sigma 5 ones. They are direct bolt on....same hole pattern, shaft size. The new servos are half the length as the old ones. Makes its easier to work on the X axis with the servo still bolted on.
5. Run purchased servo wires to the drives
6. Make CN1 cables. This is the labor intensive part of the job. The CN1 cables supplies the +-10 volt reference signal to the drives and passes encoder pulse to the AXS board. I located a place to buy the the encoder and ref signal connectors/pins so its plug and play without hacking into your old wiring. Servo ON, drive fault, drive reset and 24VDC also gets hooked into CN1. I made a pinout sheet that shows where they hook onto the sigma 5 CN1 connector.
7. The old yaskawa X servo had a 110VDC brake.....the sigma 5 has a 24VDC brake. Just need to take the 110 wires off the brake relay and wire in 24VDC.
8. Convert parameters from old cacr drives to the new sigma 5 drives. I got my hands on the yasakwa conversion sheet. you can download sigmawin+ from the yaskawa website for free. This lets you hook a computer to the drives using a USB cable.
9. Test encoder count in control.
10. Tune DX-32 control to new drives. The new drives behave very much like the old drives. They are very close.
The new servo system is much quieter than the old stuff. It seams to move smoother. Doing the last bit of tuning this week when i find the time. I ran a 3HR program and it gave me no errors. My POS-Error is very close where it should be. The rest of the control will die one day...when that day comes i will decide if i want to repair it or retrofit it to centroid....atleast the servo system will be recent.
My next project is to retrofit the spindle drive to a new yaskawa unit...pending if they can convert the parameters for me. a new spindle drive is aprox 2500. Im also going to add LED bar graph load meters to the control.
I expect to get 15-20 years out of the new electronics. I do not use this machine 40 hours a week. More like 1 hour.LOL
I extracted all the data out of the original hard drive using winimage. loaded that info onto a compact flash card and run a compact flash reader just like the centroid controls. This cost me aprox 20 bucks in hardware. I did that mod 3 years ago. Makes it easy to keep back up copies of the software. I replaced the motherboard with an industrial PC motherboard with a 266mhz processor. It really made the control run better and not lock up. I bought 3 of these boards and graphics cards brand new on ebay for a good deal. got lucky one day and bought a brand new keyboard for this machine on ebay for 12 bucks.LOL what a steal.
I replaced the computer power supply with a corsair unit. had to use ATX to AT adapter to hook it to the motherboard.
Machines that have Yaskawa sigma drives (sigma 1 or sigma 2) are even easier to retrofit because you can hook a cable to the old drives and use sigmawin to convert the parameters for you.
I spent a great deal of time doing research and comparing the specs of the old servo system to the new sigma 5 system. spend allot of time looking at the machine schematic and comparing wiring specs from the old drive to the new drives. I really did my homework on this before spending the money and risking killing a working machine. You dont need to be a master electronics guy to figure this stuff out but you will need to have some skills to pull this off. Ive retroffited 3 bridgeports to centroid systems.....I didnt have any trouble. The big thing is to take pictures of everything, record where wires went and double check all your connections to the AXS board....this is wired directly to the BMDC so you dont want to wire it wrong and burn the board up. The machine schematic gives you the pinout for the ref voltage connectors and the encoder feedback connectors.