Anyone know where I can learn the steps for reprogramming the VFD on my G0766 - I want a "super slow mode" for when I am power sanding. Thanks in advance, JN
David Roseman is our go to guy for the VFD programming.....hopefully he will see this and respond. He knows!
John, I'm curious what you would want for the lowest speed.
mine goes down to 50 rpm not sure why you would want it any slower than that.
Mine is pretty adamant about not going below 100 rpm. I won't know "how slow" until I experiment and also until I know what is possible. Besides slow for better sanding, there is also slow for extended periods of time while an epoxy coating sets up that I'd like to play around with.
Mine also goes down to 50 rpm. Do you have yours on the low speed pulley? If on the high speed pulley, your lowest speed will be higher.
Yeah, I'm on slow speed pulley - mine has always (4 years now) intermittently cut out on me when dialed back below 100 rpm. I figured that was a warning sign. I'll have to find the link to share, but I now remember seeing a video about someone rigging up an off-the-lathe chuck holder and wooden turned pulleys - drive end attached to the lathe spindle - lathe turned at 100+ rpm and chuck holder at like 4 rpm. Of course, the opposite could be fun, too. Do you suppose with a well balanced 22 inch walnut bowl spinning at 75,000 rpm I could levitate a G0766?
You will have to keep an eye on the temp of your motor if you run it at that speed very long it will burn it up.
John, Hmm, I don't know why you're cutting out intermittently below 100 rpm. The G0766s all supposedly can turn at 50 rpm spindle speed. As you note, it's possible to come up with a mechanical jack shaft-and pulley design to further reduce your lowest speed, although that seems like a whole lot of effort for very small gain. Each to his own, of course. I've never wanted or seen any value in sanding that slowly, although your point on epoxy adhesive is interesting. As for modifying the VFD programming on the G0766 (and its cousin, the G0733), I've never investigated it as a way to change low-end motor speed selectively without affecting the motor speed across the board. I'm no EE like Brice and some of our other SMC members, but if that is so, I assume that reducing low-end speed by reducing the output frequency would also reduce high-end speed, with corresponding torque reduction at the higher end. Not something I would want to tinker with. [cont]
On the seven G0766s I've helped make adjustments on, I first recorded Grizzly's as-shipped parameter settings before making changes. On those lathes, at least, Grizzly used the Delta default setting for Maximum Output Frequency. Unless your lathe is a real outlier, I would assume it is programmed for that, as well. If you do want to explore parameter adjustments on the VFD-M series, I'll be happy to send you a write-up that I did three years ago. It was current at that time. Just PM me with your email address. I'll add that Grizzly, like other manufacturers, locks out the VFD's digital keypad to avoid ill-advised or inadvertent tinkering by the end-user that could have serious consequences. You would thus need to go in through the telecommunication interface, and that will require specialized hardware, as well as downloading Delta Electronic's free software and the appropriate user manual.
