[juzwuz]

Hi! I just acquired a Precise Super Cycle 65 Powerquill grinding spindle (SC1165) and I'm hoping to use it on a cnc router. Of course it didn't come with cables or the driver. It says on the plate: Connect only to precise frequency converter Max. HP 3/4, working range 15000 to 54000 rpm, max rpm at 900Hz 165 volts 3.5 amps full load.

Would a VFD work to drive this spindle? I was thinking a Danfoss VLT2800 seems to have pretty close characteristics: input 1 phase 220v 10.6amps
output 3 phase 0-1000Hz 4.2Amps 1.7kva Anybody have experience with this spindle?

Thanks!

[awerby]

Hi! I just acquired a Precise Super Cycle 65 Powerquill grinding spindle (SC1165) and I'm hoping to use it on a cnc router. Of course it didn't come with cables or the driver. It says on the plate: Connect only to precise frequency converter Max. HP 3/4, working range 15000 to 54000 rpm, max rpm at 900Hz 165 volts 3.5 amps full load.

Would a VFD work to drive this spindle? I was thinking a Danfoss VLT2800 seems to have pretty close characteristics: input 1 phase 220v 10.6amps
output 3 phase 0-1000Hz 4.2Amps 1.7kva Anybody have experience with this spindle?

Thanks!

[I got a similar unit recently, and wondered if you ever figured this one out, and got that spindle spinning. From the research I've done, these converters are not in abundant supply. Are these really 3phase motors, which are possible to control with a VFD, or 2-phase, like a lot of the other spindles that Precise/Rockwell made? Does anyone out there know how to deal with these things?]

Andrew Werby
www.computersculpture.com

[juzwuz]

Hi! I've seen your website before while googling cam software. Pretty neat!

I haven't had time to try and get the spindle spinning but I did eventually buy a Danfoss VFD VLT2800. There are a lot of regular Precise spindles which you control with a variac but the spindle I have is definitely 3 phase. I saw the Precise VFD that goes with the spindle on ebay but it went for over $400. I think the real clue to 3 phase is that the spindle states that it gets max rpm at 900Hz. My next step is to somehow get a 220V outlet put into the garage so that I can power the VFD. I'm not sure how that is done or how much it will cost for someone to put it in.

Let me know if you figure out the connectors and wiring. Thanks!

[awerby]

Thanks for the kind words about my site. Let me know if I can answer any questions about CAM software for you.

If this is really a 3-phase device, then a VFD should work to control it. The tool hasn't actually arrived yet, so I haven't had a chance to delve into the connections etc., but the VFD folks might be helpful in that regard. 900 hz seems to be on the upper end of available frequencies, so that will eliminate most contenders. I have another Precise spindle; it's a Powerquill Super 70, the type you refer to that is controlled more simply. I'd still like to find some collets that fit it, though...

[neilw20]

i use a 2KW (max 3000hz) Talent Inverter VFD. See www.talent-hk.com
or more easily http://www.zgc168.org/user/talent/index_en.asp
Their spec on the name plate is BS at 4KW given the limited input current of 10A.
Once the acceleration ramp is set correctly, so that not too much voltage is output at the lower frequencies, I have been repairing and testing these motors using a VFD.
As a bonus (and overkill?) I run the 3 phase suds pump on my lathe with the VFD, so I don't have to fork out $huge$ for the 2 extra phases I don't get delivered to my meter.