Requiem for a Circular Saw.

[RJSakowski]

My 53 y.o. Craftsman circular saw gave up its blue smoke yesterday. It was the first power tool that I bought. It has had a had but productive life, having cut concrete block and 7/8" thick steel plate among other things. It was well built saw with die cast aluminum housing and served me well.

An autopsy revealed that the field windings had totally failed, Curiously, the wire used was aluminum. At the time, as I recall, aluminum was the latest 5thing, expected to replace copper for electrical wiring.. The rest of the saw, including the armature, looked to be in good shape and the field coils are simple enough so I am thinking about rewinding them. The wire used was .045" diameter which looks to be 17AWG. Copper is a better conductor than aluminum and the rule of thumb is you can go up two wire gauges by substituting copper for aluminum so I would be safe in going to 18AWG copper. Ir will make a nice winter project.

Meanwhile, it's off to the local DIY for a new saw. I doubt that I will see fifty years of use from it though. But then, I haven't got fifty years left in me either.

 

[MikeInOr]

DIY store for a new circular saw? HomeDepot or Lowes? Heavens no! Around here worm drive Skill saws can almost always be found on Craigslist in the $50 range and from my experience they should be a good 50 year saw.

 

[RJSakowski]

DIY store for a new circular saw? HomeDepot or Lowes? Heavens no! Around here worm drive Skill saws can almost always be found on Craigslist in the $50 range and from my experience they should be a good 50 year saw.

I check Craigslist and there are no worm drive saws at any price within 100 miles. Most of the offerings a close to new price and add to that the cost of driving for a saw of questionable pedigree. Were I a contractor, there would be no issue but my use is infrequent at this point.

I am also at a point in my life where I am not interested in acquiring someone else's problems. I do buy used tools and equipment but at a price where I can walk away from it with no hard feelings.

I ended up buying a mid range Skilsaw for less than $45. I am aware that the plastic motor housing will be less durable than my old Craftsman and I have no expectation of a 50+ year life but hey, I probably haven't much more than ten more useful tears myself.

I am seriously considering bringing the old Craftsman back to life though. I will need 120 ft of 18 AWG wire which I can buy on eBay for less than $14. It will be an interesting challenge and if successful, I'll have a saw that I can use for all the dirty work.

 

[Manual Mac]

Pawn shops usually have a few worm drive skilsaw at reasonable prices.
And they expect to dicker with you on price. I actually think they enjoy it.
I use my worm & sidewinder saws frequently.

EDIT: as a matter of fact there’s the old girl 5 min ago, cutting 2”thick 16” wide board for a workbench to put an old woodworking vise on in a new tractor shed i’m building.
Gotta keep machine work separate from wood work.

 

[Bi11Hudson]

I admire your determination to rebuild a "series universal" motor. I really do, but. . . Other than the fact the motor runs faster than a straight induction motor, it serves no real purpose. I would much prefer an induction motor as the preferable device.

Although, when you speak of "circular" saw, are you refering to a hand held, portable "Skil" saw? In which case, I would advise just replacing it. In the first place, you would want copper rather than aluminium wire. But the current drawn by the copper would be radically different. The number of turns would need to be increased. I'm sure that a conversion formula exists but I don't feel inclined to look for one.

And using aluminium wire would be a poor move. It "work hardens" easier than copper and there isn't really isn't room for a hand wound coil in the case. Plus, aluminium is a very poor current carrying conductor. And that is professional advice. Actually, even copper would be difficult to stuff back into the case. The aluminium wire is indicative of the point where Sears started to "cheapen" their products to stay competitive. Plus the fact that Sears tends to have tools, and other stuff, built "non-standard" sizes so non-Sears parts won't fit.

My opinion, both as an electrician and a (one time) professional carpenter would be to sit the saw on a shelf with a placque denoting it as the first power tool ever owned and leave it at that. I still have a Black & Decker saw that I purchased in 1972 at $30. Which I guess now is 50 years. Although the cheapest saw I could find at the time, it was and I still consider it, a better saw than the Sears. It had copper windings. I haven't used it for over 20 years, just saving it for some young man in a bind. Nothing gets thrown away. . . I also have another saw, can't think of the name, that I acquired used. From the early '60s, I think. Maybe older. I use it for cutting sheet metal, with an old blade turned backward. The bearings are bad, but that sort of work it doesn't matter.

I currently use a Porter-Cable "Skil" saw for carpenter work. Metal case, 3 wire cable, copper windings, a good blade, a much better saw than Sears ever built. And the blade makes any saw good or not so good. Last I looked, the Porter-Cable saw was less than $100, new. The motor winding copper would cost near that. And figure new brushes and reconditioning the commutator would drive any but a professional motor man up a wall. If you could even find proper brushes. . . There is much to rebuilding a small motor beyond rewinding the stator.

Pawn shops usually have a few worm drive skilsaw at reasonable prices.

A Skil 77 is a heavy saw, I have one, that suits professional or at least serious work. They can often be found for less than $200. But a worm drive saw is a hand full and not really suited for casual use. It uses a 7-1/4 blade. I also have a Skil worm saw that uses an 8-1/2 blade. But that is well beyond "casual" use. Mine is set up with a composition blade for cutting grooving concrete so a break will be where it's wanted when hammered.

All in all, my (professional) opinion is to get a decent saw and "retire" the Sears.

.

 

[MikeInOr]

I always found my worm drive saw easier to control than a direct drive saw. With the handle considerably behind the saw blade and the directional axis of the saw I find that I can much more easily steer the saw with side to side movements of the handle instead of the twisting action of my wrist required when the handle is directly above the directional axis of the saw. Make sense? I know everyone has there preferred way of working and even my magnesium worm drive is very heavy. I just guess I never thought it that heavy since my other circular saw is my Father's Porter Cable saw from the 50's.

Despite Bill's comments, which all make a LOT of sense, I hope you still decide to rewind the Craftsman saw "WITH GREAT CARE!". If you don't mind investing the time I would be very interested in hearing what you learn through the process even if it isn't successful.

I respect your decision to buy something that just works. In my area there are 9 worm drive saws on CL with 6 of them being $50 and under. There is even a nice looking 12" blade monster for $75. It was just a suggestion though.

 

[westerner]

I always found my worm drive saw easier to control than a direct drive saw.

Me too. For a right handed man, the blade MUST be on the left side of the saw. Nearly all direct drives have the blade on the 'safe' side.
One exception is the Porter Cable 'Saw Boss'. Only a 6 inch blade, but pulls it well. Direct drive but the blade on the correct (left) side.

 

[RJSakowski]

I bought a new saw yesterday. The rewind/reclaim of the Craftsman saw is an experiment. If it works, I'll have a second saw and have gained some knowledge and had some fun. If it doesn't, I'll have gained some knowledge and had some fun. At most, I'll have less than $20 and some time invested. That's what this hobby is all about, isn't it?

Generally, the conversion from copper to aluminum wire requires dropping two AWG gauges. Rewinding the field coils will be relatively easy as there is more than ample room for threading the bobbin. I will use 19 AWG copper wire for the coils. This is fairly close to the resistance per foot of the OEM 17 AWG aluminum wire.

 

[RJSakowski]

Me too. For a right handed man, the blade MUST be on the left side of the saw. Nearly all direct drives have the blade on the 'safe' side.
One exception is the Porter Cable 'Saw Boss'. Only a 6 inch blade, but pulls it well. Direct drive but the blade on the correct (left) side.

I'm a lefty. I have to use my right hand to run the saw and my left hand on the auxiliary knob. Actually, I more often use my left hand only so I can get a better line of sight on the cut.

I had considered a worm drive saw but decided against it. I don't want the extra weight or bulk and I don't need the extra performance. I use the saw for rough cutting plywood sheets so I don't have to manhandle them on my table saw or doing some odd in situ cutting. For example, when the saw quit, I was chamfering the bottom edge of a 8" x 10" sill beam . The beam was in situ on a 130 y.o. granary and actually below grade. To make the 45º chamfer, the main part of the plate was below and the 1-1/4" part running along the vertical surface. Awkward to say the least. Previously, I was cutting some of the old shiplap siding on the building to make it easier to remove. I can't imagine trying to manhandle a worm drive saw is those situations.

 

[woodchucker]

I'm a left too. So I bought a Porter Cable left saw years ago. If I had to do it over, I think I would have gone worm gear instead. I like my saw, but it's a Porter Cable (heavy).. so for the weight, I might has well have gotten the worm...

A Skill saw is a nice worm...

edit: BTW I totally blew a brand new blade one time when I put it on backwards... DON'T ASK... what an idiot I was.. I knew I had to mount it the right way, and I still managed to screw it up.