Hawk G426 Scrollsaw repair

[wjt]

The retirement village where I volunteer in the wood shop had a visitor yesterday. One of the residents stopped in and after several minutes of conversation he told me he used to do a lot of scrollsawing. He noted the little RBI saw we have currently. He said he has a larger Hawk (now RBI) unit which he would donate. We would, however, have to repair it. 15 minutes later we had brought the saw to the shop.

It is a Hawk Woodworking model G426.

The problem is the motor. When running at slow speed it runs continuously. As you speed it up (a variable speed model) the motor will stutter - that is run for a second, stop for a second, etc. When I checked the RBI website there is no fix for this motor / controller. They only sell a new unit for $350.00 Not an option.

My question is has anyone encountered this problem and been able to repair it. After talking to an electrician friend he felt it was most likely the controller.

Thanks,

Bill

[Admiral]

Edit your topic to say "electrical" repair and TDKPE, along with the other electric gurus here, will show up and give you some quality advice and suggested direction. I'm no expert, but I sense there must be some workaround to buying the combined unit for $350 from RBI.

[fredhargis]

Getting Tom's opinion is a good thing, but from what I've read the controller on those (I have one) does fail and can only be replaced. I bought mine off CL  a couple of years ago for $200....which may still be too much for the retirement village, but certainly better than $350.

[EvilTwin]

Getting Tom's opinion is a good thing, but from what I've read the controller on those (I have one) does fail and can only be replaced. I bought mine off CL  a couple of years ago for $200....which may still be too much for the retirement village, but certainly better than $350.

That saw uses a 90v dc motor with a small controller to vary the speed.  The problem could be the motor itself or the controller.   Motor issues may be dirty or have worn brushes.  Controller could be any type of electrical issue, but the good news with that is that replacement controllers can be had on Amazon for 20 bucks and up.  Just need to find one rated up to the motors 90vdc and mount it to the table next to the saw and wire it in.  

Basic troubleshooting would be to open up the controller and look for any burning or popped components like caps.  On the motor, I would try and run it without the blade (no load) and see if it acts any differently.  Could also remove the motor from the saw and see how far it can be disassembled or if there is a provision to replace the brushes.

Take some pix and you can get more detailed advice.  HTH

One of the controllers available on Amazon: