PM66 Arbor Question

[Doug Shepard]

For the last year or so I've had an issue with the arbor on my TS. I won't call it a problem as it doesn't seem to affect anything other than tightening or loosening the arbor nut for blade changes. At some point the nut may have gotten overtightened then when later removing the nut the arbor seems to have loosened somehow along with the nut. The whole arbor seems able to turn but as near as I can tell it hasn't affected the right-to-left position of the arbor flange. The blade always goes up dead center through the slot on the zero-clearance insert. There are no vibration issues and there doesnt seem to be any play or slop, but the arbor will rotate in it's housing which causes nut installation or removal a bit of a nuisance. Any ideas how to correct this?

[CPeter James]

I have a PM66 and have had the whole arbor assembly apart and I don't understand the question. Does you arbor have some kind of a lock that is supposed to allow removal of the arbor nut without holding the blade? On mine the arbor is held in place with a set screw that clamps down on a space that is trapped between the two arbor bearings. Side to side adjustment is made via this set screw. Give me a few more clues and maybe I can help.

CPeter

[Doug Shepard]

I have a PM66 and have had the whole arbor assembly apart and I don't understand the question. Does you arbor have some kind of a lock that is supposed to allow removal of the arbor nut without holding the blade? On mine the arbor is held in place with a set screw that clamps down on a space that is trapped between the two arbor bearings. Side to side adjustment is made via this set screw. Give me a few more clues and maybe I can help.

CPeter

No arbor lock on mine either. Maybe all I need to do is tighten that set screw? Does the set screw bottom out on a flat area of the arbor shaft or is it completely round? There doesn't seem to be any side to side movement, but when you try to tighten or loosen the arbor nut, you end up turning the whole spindle. It usually takes 2-3 tries before I can get enough bite with the wrench to start the nut turning independently from the spindle. Makes blade changes a bit annoying.

[Jim DeLaney]

Doug,
Do the belts - and the motor - turn too when this happens? if not, perhaps you just need to retension the belts.

Are you overtightening the nut when you install the blade?

Fwiw, when I install a blade on my Shop Fox cabinet saw, I only tighten the nut maybe 1/8 ~ 1/4 turn beyond finger tight. The actual turning of the arbor while the saw is running will tend to tighten the nut. I've never had a problem with blade slippage.

When removing the blade, I hold a piece of wood against the teeth of the blade and just pull the wrench toward me fairly gently. It doesn't take much force at all to break the nut loose.

[Ralph Steffey]

when ever I use a dado blade on my pm 66 it seems to bugger up the threads on the arbor making it very aggrivating to put the blade back on I have to take a large pair of channel lock pliers and hold the flange behind the blade till the nut re chases the threads then it is fine till I use the dado again. I think you are thinking the motor and belt tenson should hold the arbor still but it doesnot.

[tod evans]

doug, the old 65 and 66 arbors where set up identical, if you have no side to side movement of the blade, left-right, the set screw is doing its job. from your description it sounds as though when off the arbor is able to spin freely of the motor? hence making loosening the nut dificult? if so check belt tension, when the arbor nut is turned untill it breaks loose the motor should also turn. if the belts are in propper adjustment then all sounds right with the assembly and most likely what you`re experiencing is the nut tightening itself during use. when i change blades in any table saw i jamb a piece of pine into the teeth and tug sharply on the wrench to break the nut free. if this technique doesn`t work then the arbor is spinning within the bore of the blade meaning that for some reason the machined washer isn`t contacting the blade fully when tightened..check these few things and see if they help...02 tod

[Doug Shepard]

Thanks guys.
I am doing the stick-in-the-teeth method to hold the blade from turning. While not normally overtightening I think a past instance or two of tightening too much might have started this little problem. I dont think I've got a buggered thread problem. I've run the nut on/off the arbor with no blade on and it turns freely all the way with no binding or slippage. I'm going to try tensioning the belts to see what happens. That sounds like it might be the most likely fix.
Muchos gracias.

[Jim DeLaney]

...I am doing the stick-in-the-teeth method to hold the blade from turning...

Interesting description. My method is to fairly gently slide a piece of wood - pine works well - along the table top and into the leading edge of the blade, with the blade fully raised. Then, I use a wrench and just pull - not particularly hard - on the nut. It generally comes right off with just a light tug on the wrench.

BTW, I tossed the OEM stamped wrench out and bought a nice Craftsman box/open wrench to use. I keep it right on the front of the saw, using a 1" neodymium magnet to hold it in place. Keeps it handy, and the good wrench is much nicer to use than the OEM POS.