Table Saw Arbor Threads

[Steve Kirincich]

A couple of years ago I purchased a used Jet cabinet saw. It is in very condition and was previously owned by a hobbyist woodworker. I have noticed that the nut turns on the shaft with some resistance and changing blades is somewhat difficult. From the photo, it appears that the years of use have resulted in some deformation (spreading?) of the shaft threads. I have verified that the nut is not the problem. I can certainly live with this situation. Would I regret running a 5/8" reverse acme thread die over the shaft threading as a possible solution?

Thanks!
Steve


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[Bill Dufour]

Are you sure the are acme not buttress threads? Check with a thread gauge. Could they be metric spacing on a 5/8 shaft.
Bill D.

[Matt Day]

Have had similar issues with my Unisaw. First clean it up with a quick hit of sandpaper with it running (without the blade on of course) then try a little lube. That might do the trick.

If not a small triangle file through the threads will knock down any little burrs.

[Jerry Bruette]

I think those threads look pretty nice to me. I think if you gave them a little attention with some 320 grit and then wire brushed them your fit might improve.

[glenn bradley]

I agree on not getting too aggressive just yet. I would start with a wire brush and then move to a folded bit of fine sandpaper or a fine triangle file and a LIGHT touch if the wire brush didn't do the trick. One question is how did you determine the nut was OK? Do you have another one of these saws that you tested it on. My point is that a test is only as good as its accuracy in duplicating the actual environment. Spinning it onto a bolt wouldn't count ;-) Being used it could be that the previous owner fed the original nut to his DC and found a 'reasonable' replacement. Just spit-balling.

[Bill Dufour]

Chrysler products, and a few rare others, used to use left hand threads on one side for wheel nuts. Auto parts store may have a nice new left hand nut for cheap. Not sure on thread form though.
Bill D

[Steve Kirincich]

I bought this cabinet saw after my contractor saw's lift gear was beyond repair, and I still have parts from this saw in my basement. The nut that came with the Jet cabinet saw threads smoothly on the arbor spindle from my contractor saw. The nut from the contractor saw is a very tight fit on the cabinet saw arbor. The problem is clearly related to the threads - the nuts from the two saws, but the one from the cabinet saw has been slightly modified from being rotated around the slightly deformed threads. The fit is definitely not an issue with crud building up in the threads. As suggested, I may gently use a small triangular file on the threads.

[Lee Schierer]

Before attacking the threads with a file or sandpaper, lube the threads on the arbor and nut with paste wax. Make sure your nut is the correct type for the threads on your arbor.
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[Steve Kirincich]

Thanks Lee. The paste wax nicely reduced the friction.

[Bernie Kopfer]

I one time put a full thickness Dado set on my PM 66a nd maybe also the washer. Tightened the nut but only about 2/3 of the threads engaged. Ever since then the nut has gone on hard. Obviously I had distorted the threads slightly on the shaft. Livable, but irritating. Perhaps that is what happened once to your saw Steve.

[Lee Schierer]

I one time put a full thickness Dado set on my PM 66a nd maybe also the washer. Tightened the nut but only about 2/3 of the threads engaged. Ever since then the nut has gone on hard. Obviously I had distorted the threads slightly on the shaft. Livable, but irritating. Perhaps that is what happened once to your saw Steve.

When I run my dado blade on my saw, I don't use the outer washer that fits on the arbor shaft for exactly that reason.

[Michael Schuch]

I would not run a die over the threads. You are likely to mess up the threads and make them too loose.

I would hit the arbor with a stiff steel brush while the arbor is spinning without the blade on it. Then I would put a bit of Johnsons paste wax on it. When I got my '47 radial arm saw the arbor nut was very tight. A bit of cleaning and paste wax smoothed it out initially then just normal use and blade changes kept it from ever binding again.