Craftsman variable speed bench grinder won't adjust speed
 

I was given this grinder a couple christmases ago, havent really ever used it until recently. Craftsman Variable Speed 8 Bench Grinder: Power Up With DealsSears

The variable speed knob doesnt do anything, the the unit appears to run at full speed all the time. It worked the first couple of times I used the unit but hasnt since. Thing maybe has 20 minutes of run time on it.

I took the knob off the shaft and turned the shaft by hand to make sure the knob wasnt just slipping on the shaft and it still feels normal so I am out of ideas short of taking it apart and tinkering with it.

VFD is probably bad or the controller in the motor

I'm sure it's just a potentiometer that controls the speed... Pick one up from radio shack and wire it in and see!!!

I pulled it apart and tested the resistance of the leads of the knob, 10.2kohms at low and 9.8 at high....that doesnt seem quite right.

No it doesn't, seems like there should be more of a range than that.

Your thread title= oxymoron.

Similar story , I got a nice ( I thought) craftsman timing light for Christmas 3 years ago , needed it this past summer , it didn't work , tried it on another vehicle , no dice . Wayyy too late to take it back . FML :(

it's a craftman. take it to sears and get a new one.

thats only for handtools. most power tools have a 1 year warranty and you need a receipt.

throw a mini shit fit and sears will cave every time.

Buy new one, take old one back and say it doesn't work. You get a new one and no problems.