Woodworkers: Worn Table Saw Motor - Fix or Forget it?

In My Humble Opinion
1

Hey, guys!

Over a year ago, a coworker gave me an old Craftsman 113_299040 table saw that used to belong to his father and was gathering dust in his backyard shed. I cleaned off all the crusted sawdust and pitch, then let it sit in my garage for quite a while and even moved it from my old place to the new place.

I tried to cut a peg-board 4x8 in half with the panel-cutting blade that was already on the machine. While it did the job, there was a lot of smoke in the garage when I was done. I figured that was because my wife was ‘pinching’ the blade while she was helping me (I was pushing, she was pulling and keeping the out-feed from hitting the floor). But I was preoccupied with my project and didn’t give it much thought after that. Recently, though, I tried to cut a 1/4-inch plywood panel and got the same smoke along with burnt edges. I thought it might be either the blade angle or a warped blade, so I replaced the old blade with a new DeWalt 40T and got a digital caliper and managed to reduce the difference between the front and back of the blade to 2/1000ths of an inch, when measured to the inside of the nearest accessory slot. I also took the time to make sure the front and back of the fence were aligning properly, as well.

When I tried a test-cut on a 3x3 block of scrap, I got the smoke again. And, since I cut only a groove part-way into the block, I could see that the sides of the cut were burnt but the floor (ceiling?) of the cut was clean and unblemished. So it’s seeming like the motor of this old table-saw is so old that it is running slower than is good for a burn-free cut. Too slow would cause burning, rather than too fast? I’m not thinking the motor would get faster with age.

It’s looking like this table-saw was sold by Sears in the early and mid-1970’s. The stuff I see at Sears is much newer designs, but I’ve heard their quality went to hell in the late 1980’s. How difficult would it be to replace the motor with a new one that will both fit the design and run at a proper speed? How much would that cost, and where does one look for such a replacement motor?

All I’ve done with the machine so far is clean it off, add a dust-catching bag, and put a new blade on. There’s not much left other than a table, fence, and angle/height adjustments. I got some safety pushers and was considering ordering a Shark aftermarket guard kit, but perhaps it’s good that I waited. Maybe I should pitch the worn-out table-saw and go back to relying on my circular saw?

–G?

Once you’ve got that money
It cost more now
It might cost a lot more
than you think…
…–Axl Rose (Guns N’ Roses)
…Pretty Tied Up
…Use Your Illusion II

2

If the motor was running slow it would be smoking not the wood burning. If the wood is burning my experience is blade and not cutting straight.

3

I agree - smoke is a function of friction.

A defective motor would be more likely to stall or slow down. Obviously, the motor is putting out enough speed and torque to not only cut, but burn as well.

If the saw has a cast iron table, KEEP IT.

Find out why it is binding.

A few drops of oil on the blade may reduce the binding and the resultant friction.

I think I may have just found the problem - that is a 6 1/2" blade that sells for less than $10.
Cutting tools are expensive. Buying tools you can’t use is not good budgeting.

p.s. - the cut is called the Kerf. The kerf is determined by the width of the blade, along with tooth offset (if any)

4

I wouldn’t spend too much time or money trying to fix it. It’s not a fantastic table saw, but it is good enough for construction and most woodworking tasks. I had a similar Craftsman given to me by someone with a replacement motor. I dumped it before long. New equivalents run $300-$400, so before spending a lot consider if it’s just better to put a little more money in for a new one. But first step should be to get a new belt. If the belt is old it’s probably slipping. If it’s a gravity tension unit the motor should be on a swing arm to tension the belt so make sure that arm moves freely. Lubricate everything, then try again. The good thing is that there are a lot of old Craftsman table saws out there, typically available for about $50 off Craig’s list and the like (don’t spend more, it’s not worth it), so you can a set of replacement parts for no more than that. The bad part of that is nearly every motor is worn out, and they weren’t that good to start with because they were underpowered.

5

Yeah, I kinda thought my analysis was flawed.

Tried that; didn’t help.

That’s the super-hard part, for me. Like my body, age has negatively affected proper operations.

That’s why I’m wanting to keep it – provided a fix can be done without too much cost.

A 6.5" blade on a table-saw? I can imagine it would work, but it seems that would increase the speed – and friction, and smoke…

Yeah, and even though this was given to me free, I’d really like to make it function properly – mainly because it’s got the good table, but also because I’ve invested all of a hundred bucks:eek: in revitalizing it*. But this is the point where I’m contemplating cutting my losses or doubling down.

Yeah, sometimes my attempt to be frugal ends up costing me more.

The odd thing is that this model has a motor which is directly driving that blade – no belt, no worm drive, no gears – just a motor on funky adjustable arms. Part of the problem was that there’s no trundle bolts for adjusting the blade angle in relation to the slot/fence. I ended up propping a block of wood against the shaft and whacking it with a hammer as if I had loosened trundle bolts that don’t exist. That brought it back closer to parallel (see OP) and I even checked afterward to make sure the blade wasn’t wobbling from a bent shaft. But still it’s burning scraps.

Yeah, I’ve looked at a couple of those e-bay specials. The ones I’ve seen talk about motors needing replacement, so I’m not so willing to buy someone else’s table to end up harvesting a motor that’s no better than what I’ve got.

For my occasional hobby work, I’m leaning toward Rigid (Home Depot) rather than Craftsman – but I’ve heard rumor that they’re the same manufacturer sticking different paint jobs on the products. I certainly can’t afford Jet or Ryobi or SawStop, and I’d really rather keep this old thing and make it work right.

I thank you all for your input!

–G!
*As I said, I know I’m possibly being too cheap about this…

The left says [COLOR=DarkGreen]Yes
and the right says No

I’m in between
and the more I learn
well the less that I know
[/COLOR]
…–Dennis DeYoung (Styx)
…Borrowed Time
…Cornerstone