[Lathe] Fanuc OT to DC_CNC conversion

Down the rabbit hole.
I have faith you'll get it going.
From what I've seen as far as prices on that used fanuc stuff you should be able to recoup alot of the expense of the conversion
by selling the used parts.
 
Well I determined that the 7.5 KW spindle motor is in fact a standard(ish) 3 phase motor so a VFD will run it just fine. I did hear back from Automation Direct they said '' The GS3 is designed for continuous velocity operation with 3-phase induction type motors. It cannot perform positioning movements.'' We'll see about that. :cautious:

I removed all of the servo motors today, that was a pretty major job. It was like working on a late model car, pretty tight in there and lots of sheet metal to remove. I'll get the new motors and drives ordered tomorrow.
 
I spent most of the last few days tracing wires, pulling old cables out, working up a BOM, and creating an I/O map and a schematic.

About the only thing that's left in the power cabinet is the contactors for the hydraulic and coolant pumps, 3 breakers, and a few odds & ends. I removed everything that said Fanuc on it.:) Going to add in the control power and E-stop relays, and a breaker and contactor for each of the servo drives.

As of yesterday the new servos and drives are on order, unknown delivery time, but are in stock and coming out of Vancouver, BC. So maybe 3 or 4 days.

4) 1.8 KW servo motors for the axes and live tooling.
4) DYN4 240V servo amps (drives)
From DMM Technology

The spindle VFD is a GS3 10 HP from Automation Direct. Should be here tomorrow.

This is just one pile of cables :grin: I've added to it since this picture was taken.

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Well things are going to start moving again, the servo motors and drives came in yesterday and I have some time to work on the lathe. I have a whole pile of parts to install. Should keep me busy for the next couple of days.

Pictures to follow....stay tuned. :)

Christmas in March :)

The new drive system parts overview

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Dyn4 drives from DMM Technologies 240V, 30 Amp

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Axis, tool turret, and live tooling servos. From DMM Technologies, 1.8 KW. A bit more power than the original motors.

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The drive breakers, contactors, control power & E-stop relays from Automation Direct
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10HP GS3 spindle drive VFD from Automation Direct
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Now comes the fun, installing all of this stuff. Gonna be busy for a bit. :)
 
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Looks like you are going top shelf. I plan to copy you for my mill. But only after you know all the gotchas :)

Was the servos a one time deal, or can I look at buying them for my mill?

Am I correct that a galil card is still at the heart of your control?


BTW, I originally used that exact 10 hp GS3 drive on my Hardinge CHNC. Turns out it has a three phase detection circuit I couldn't beat. I wanted to run the lathe on 220 single phase. Automation direct was great. They took it back and sold me a GS2 unit.
 
I hope the DMM servos work out OK. I have heard good things about them, so I went that way. The DMM is going to be my go to servo vendor if I'm happy, I have to say that DMM tech support was very responsive to the couple of pre-purchase questions I had. We'll see how the after sale support is if I need it. It was nice to pick up the phone and actually have someone on the other end that actually spoke English (well, Canadian anyway, 'eh :) )

I'm thinking about replacing the steppers on my router with servos also. Equivalent servos and drives actually cost less than I paid for my steppers and drives. The other reason that I went with the DMM rather than ClearPath is that the DMM drives will accept both analog and step & direction and allow you to close the loop at the controller. Not possible with the ClearPath units.

Yes, the Galil is the heart of my controller. I'm modifying my software to run the lathe as well as mills and routers. My software will now do full 4 axis machining. In its current form it's running well on 3 machines, 2 mills and my router. The code for rigid tapping is written, but not yet tested. When that is completed, it will work on both a lathe and a mill.
 
Just FYI, I use galil electronic gearing for rigid tapping and gear hobbing on my CNC mill. It has run flawlessly for years. This approach did NOT work on my lathe. The difference is speed. need on a lathe is to thread at 1000 or even higher RPM.

Lathe approach was first a high speed index mark. used a slot sensor to a high speed opto 22 input. Got response in the area of a few 10EE-6 seconds. Several revolutions are first sampled to accurately determine RPM. Then the X axis is fired on the index mark to move at the calculated feed rate. With this approach total control of a G76 thread cycle works wonders. I had over a month's work just making this thread cycle run.
 
Got a little more work done. This is the servo drive panel. All four servo drives, breakers, contactors, and other parts all fit in about the same footprint as one of the original drives. Aint modern electronics great :grin: Now I just have to wire up the control power and E-stop relays (the 4 ice cube relays) and the panel will be ready to install.

There's about 8 hours of wiring time in this one.
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Whew....Looks awesome. Very anxious to see it run as I'm sure you are.
 
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