14x40 Lathe Retrofit

Thanks a bunch for you help Andy. I'm looking back into this, but this time I'm trying to keep it as simple as possible. I just have too many projects right now to overcomplicate things.

That being said, I'm going with your original advice to keep the DC servos. I'm looking at a 5I24 > 7I49 > 7I29 setup. I will use the original spindle motor and connect that resolver to the 7I49 as well. It looks like that setup will run about $600 which seems like a great deal.

I still need to research the rest of the setup, in particular the power supplies, but I feel like this is a good direction to go. I really like the control box you did on your Harrison mill and will probably try to imitate that.

I just want to make some progress at this point!

I decided I should probably double check the motors, so I opened the backend to take a look inside.

I did find a resolver and a tach as predicted. The models are:

Resolver: Summit 573-211-20
Tachometer: Sierracin Magnedyne 707-01A

The motors themselves are Summit 216-330-30. Rated for 90v 7.4A 1430RPM

A quick google search didn't yield any info outside of ebay listings, but this confirms to me that the 5I24, 7I49, 7I29, and 7I37TA are the right fit for this application. I read through the manuals on each of those boards and it did start to click. Still a little unsure how the actual connections for the resolver and tach work out but I'll get it.

I mispoke in my original post when I called said my current spindle motor was DC. It is a 3-phase AC motor, so I'll run it with a VFD I have on-hand. I would like to control it with LinuxCNC - I don't know exactly how the VFD hooks into the Mesa network but again, I'll figure it out.

I also have a resolver on the spindle, so that will feed into the 7I49

Perfect - thanks. The lathe is geared so that code could be helpful.

I went to order the cards and a couple are out of stock, so I'm waiting to hear from Mesa.

I never heard back from Mesa, so I may just go ahead and order the parts.

I tried connecting my VFD to the spindle motor last night and didn't have a lot of success. I set the parameters in my VFD (it's a Chinese 3.0KW model from HuangYang) and bypassed all switches by connecting straight to the motor. I did nothing but shudder. I spent a good 2 hours troubleshooting the problem and came to the conclusion that the VFD is likely bad. Unfortunately I bought it new about 3 years ago and never touched it until last night.

So rather than replace the VFD, I'm again looking at using the Fanuc servo as my spindle motor. You seem confident Andy that I can bypass the Fanuc encoder and use the spindle resolver instead. Mesa has a 2.2KW motor driver but I'll be looking on eBay for servo drive that is cheaper before adding that to my order.

I put some money toward this project this weekend and finally ordered some parts. I was also able to get the spindle motor moving with the VFD! But not before I ordered a servo amplifier for the Fanuc drive, which I'll keep for a potential C-axis upgrade later.

I ordered:

5I24
7I49
7I37TA
AMC 16A20ACR brushed servo amps (two, for the DC motors)
AMC B25A20N brushless PWM servo amp (for the Fanuc 10S, when I decide to use it)

I'm excited to get these parts in and setup on the bench.