Results 1 to 12 of 12

Thread: G0766 Issues

  1. #1
    Join Date
    May 2014
    Location
    Winchester, IN
    Posts
    165

    G0766 Issues

    While doing a little turning today I noticed when I turned the speed control knob "on" I get no response until I turn it at least 1/3 of the way up and the the spindle begins to turn, but the lowest speed I can set it at is about 400 rpm. I've done some reading, and it appears to be a potentiometer meter issue. That seems to be a somewhat common issue with the G0766. It's a little frustrating since the lathe is only about 6 months old. Is there anything that I should try before calling Grizzly? BTW, I'm not an electrical engineer, so please don't get technical.

  2. #2
    Just call grizzly... They should send you a new potentiometer. It's a common issue. Waiting just takes extra time. It is covered by the warranty. In the meantime if you can find a replacement locally get it. I think it's a 10 k linear pot. I'm not 100% sure about that spec so check...

    be careful removing the knob. I managed to break mine with the screwdriver. Just being clumsy. It's a small screw in a threaded inset and if you don't get the screwdriver into the screw correctly and turn it SNAP the knob is ruined.

    Clint

  3. #3
    Join Date
    May 2014
    Location
    Winchester, IN
    Posts
    165
    Thanks Clint

  4. #4
    Join Date
    Feb 2018
    Location
    Cookeville TN
    Posts
    338
    I would also call Grizzly but if you have the skill to get to the Potentiometer you could spray it with electronic cleaner, rotate it the full range a bunch of times. Do that several times. Hopefully it will solve the problem. If the Pot is sealed too well it may not work, or if there is an internal problem it won't work but an $8 can of the spray is worth a try.

  5. #5
    Join Date
    Sep 2015
    Location
    San Diego, Ca
    Posts
    1,647
    John, the pot is sealed. When my last pot failed I did a forensic analysis (I'm an electronic engineer). It was pretty simple. The very thin wire that is wound broke from mechanical wear.

    When I replaced my last pot (provided free under warranty) I also ordered two extra (spare) pots. They are really cheap. The first pot replacement took me 1/2 hour but the 2nd one took me 5 minutes. It is a pretty easy job.

  6. #6
    Join Date
    May 2014
    Location
    Winchester, IN
    Posts
    165
    Thanks Brice and John. From what I've read, this is a common is with the G0766 so I thought I would order a backup as well.

  7. #7
    Join Date
    Jan 2015
    Location
    Brentwood, TN
    Posts
    684
    Get the free warranty replacement, and search the Green Giant Machine Group threads, and many of us have to replace the potentiometers. I have done the Grizzly replacement twice in the first 2 years, so I ordered a US Made Bournes or Cutler-Hammer equivalent potentiometer for a backup (hopefully never to be used). Wish I'd done quick disconnects on the terminals, because the wires are getting shorter with every replacement. I did an autopsy on both of the failed pots, and the fine wire windings fray causing a dead spot in the sweep. Everything else on my lathe is robust, just wish Papa Grizzly would come across with a really great replacement potentiometer that can last forever (and send it to all current owners, like they did for the Banjo debacle).
    Maker of Fine Kindling, and small metal chips on the floor.
    Embellishments to the Stars - or wannabees.

  8. #8
    Join Date
    May 2014
    Location
    Winchester, IN
    Posts
    165
    Thanks Mark. Any details you can provide about the American made replacemet would be appreciated (part number). I'd really like to only replace this once instead of replacing it multiple times with equally inferior parts.

  9. #9
    Join Date
    Sep 2015
    Location
    San Diego, Ca
    Posts
    1,647
    As I recall, at least one of the connections on the original pot was soldered or crimped so that it couldn't be removed with a screwdriver. So, I cut the wire right at the pot for that wire, leaving it as long as I could. I then stripped it, dressed the wire and tinned it. Then I re-assembled things using a small wire-nut on that connection, plus added a wrap of black tape. So when it came time to do replacement #2, it was much easier. It didn't have to cut any wires or deal with wires getting shorter.

    I think that part of the problem with the Griz wire-wound pot is that with the fairly high value of a 10K pot, the wire is very fine. Only a couple a thou. There are a couple of things that I think might work a bit better:
    1. Switch to a 1 K pot (the wire will be thicker). I haven't tried this, but it appears that the function of the pot is only as a voltage divider. I recall that one end of the pot is at "ground", the other end is at a reference voltage and the wiper is part of the voltage divider.
    2. Switch to a more modern pot that uses a conductive polymer or ceramic element. It could still get "noisy" but you won't break the fine wire.
    Last edited by Brice Rogers; 04-05-2018 at 12:51 PM.

  10. #10
    Join Date
    Jan 2015
    Location
    Brentwood, TN
    Posts
    684
    https://sawmillcreek.org/group.php?d...793&do=discuss

    https://sawmillcreek.org/group.php?d...e=2&do=discuss

    These are links to the speed control potentiometer threads over on GGMG group forum.
    Maker of Fine Kindling, and small metal chips on the floor.
    Embellishments to the Stars - or wannabees.

  11. #11
    Join Date
    May 2014
    Location
    Winchester, IN
    Posts
    165
    Thank you Mark

  12. #12
    Join Date
    May 2014
    Location
    Winchester, IN
    Posts
    165
    Glad to report that I got the pot changed and it solved the problem. I appreciate everyone's input regarding the change---it made it go very smoothly. Thanks again!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •