Originally Posted by
Ayyub2007
Hello all,
I recently picked up a G0704 for cheap (mfg: 5/2010) and I cannot get it to turn faster than 1500rpm in high gear even if I let it warm up. If I grab the spindle while in high gear, I can virtually stop it and it blows the fuse. I can feel the controller (I think) compensating for the torque load but it still blows the fuse. I cannot stop the spindle at any speed in low range and it does not blow the fuse. The quill will get to 140-150 degrees after running for 4-5 minutes. I researched this problem and even called grizzly and the initial fix was to replace the spindle bearings. If I put the spindle back in without installing bearings (just holding it in place) I can still bind the motor in high gear so i am thinking it's not the spindle bearings. If I run the machine without the spindle in place, just turning the speed selector gears and the gear-set that would turn the spindle I can just break 1600rpm and if I shut the machine down, it will go from 1600-0rpm in less than 1 second. Is it normal for it to brake so quickly? I disassembled the motor and it looked good. The commutator was a bit dirty to I shined that up, checked the bearings and put it back together with no improvements. I checked the driver and it is outputting 96v at full throttle on low gear and 108v at full throttle on high gear. The mill has the original version motor, not the v2. When I called Grizzly back a second time to see what troubleshooting steps I could take, the answer was to just use low gear and run it until something completely fails and then I will know what part was the problem. Though I understand the logic, it would be great to service this unit before something catastrophic occurs, not to mention I lose out on some milling options due to speed reduction.
Any suggestions on where to start or what to look at would be much appreciated. Thanks for taking the time to read this post.