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Forum topic by jcarter524 posted 09-04-2016 12:36 PM 452 views 0 times favorited 6 replies Add to Favorites Watch
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jcarter524

2 posts in 93 days


09-04-2016 12:36 PM

I was milling up some table legs this morning and right in the middle of the cut I thought I started hearing a funny wurring noise and then the saw (pm 66 w/ 5hrse Baldor single phase [DOM 2000]) lost power. When I started it again the blade looked like it was slipping, taking its time to get up to speed, and then a clunk. I checked that the blade was tight on the arbor and then removed the blade to and verified that the bare arbor started in the same manor and the same clunk. I pulled the motor cover and the clunk (a fairly violent sound) sound like it is coming from inside the motor housing or up front in a place I could not locate.

I am not mechanically experienced, or terribly inclined. Any advice, suggestions. Hoping to avoid the repairman.

jc


6 replies so far

View toolie's profile

toolie

2023 posts in 2092 days


#1 posted 09-04-2016 01:45 PM

remove the drive belts to allow for the motor to operate independent of the blade. if upon power up, the motor make the same noise, look to the motor and it’s mounting points. if its not the motor, spin the blade and listen for the sound. your objective is to identify which component is initiating the noise.

-- there's a solution to every problem.......you just have to be willing to find it.

View Mike_D_S's profile

Mike_D_S

185 posts in 1678 days


#2 posted 09-04-2016 02:35 PM

Well, I’m no expert, but to me it sounds like an issue with a centrifugal switch. On a lot of motors, there are two sets of windings, one of which is energized all the time and one of which is energized to create a high starting torque. The starting winding brushes are on a centrifugal switch and when the motor comes up to speed, they disconnect due to the force on the assembly. The motor then runs with just the main windings.

Based on the clunk you describe, I would suspect the centrifugal switch. I think the switch unit would usually be a replaceable part.

Based on your comment about mechanical aptitude, then I think you’re going to need a repairman. Assuming a new 5HP motor is probably $500 ish, then I would think you could get it repaired much cheaper than that. The parts are probably under $100, and the replacement is not that difficult. You might be able to find somebody local who you can drop it off with and get it repaired for a reasonable amount.

I would think someone else on LJs has done this before. It’s not overly difficult to do, but you just have to be careful as the parts are heavy.

Good luck,
Mike

-- No honey, that's not new, I've had that forever......

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RogR

53 posts in 328 days


#3 posted 09-05-2016 08:53 PM



Well, I m no expert, but to me it sounds like an issue with a centrifugal switch.
- MikeDS

I have experienced a similar issue with my Shop Fox 5HP TS. In my case it has happened a half dozen (?) times in about 10 years, but not recurred with any regularity. Sometimes it pops the breaker too. Reset and restart and it carries on normally. The ghost in the machine.

View Mike_D_S's profile

Mike_D_S

185 posts in 1678 days


#4 posted 09-06-2016 12:16 AM

@RogR, the OP’s description makes it seems like it’s fairly consistent. So I’m taking bets he’ll need to actually do something about it.

-- No honey, that's not new, I've had that forever......

View jcarter524's profile

jcarter524

2 posts in 93 days


#5 posted 09-07-2016 07:17 PM

Just an update. I followed Toolie’s suggestions and couldn’t ID the problem. I pulled the motor off to take it to a motor shop and in doing so noticed that the key was missing from the motor side pully. Shop said that happens every once and a while with the set screw style and the clunk was the two keyways hooking up. They checked the shaft and pully for size. The shaft was okay but the pull was now oversized. And as a precaution they ran the motor on the bench and and everything is fine. Get it back tomorrow AM with a new “bevel tensioned pully” (supposedly a much better approach for this application). Thanks for all your help. FWIW learned that a brand new 5hrse for a 184c frame is around $560 directly from Powermatic. Much less expensive that what I saw on the auction site. Diagnostics and repair ended up being $140.

jc

View Mike_D_S's profile

Mike_D_S

185 posts in 1678 days


#6 posted 09-07-2016 08:01 PM

Glad you got out fairly cheaply.

-- No honey, that's not new, I've had that forever......

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