Table Saw Blade Breaking Loose

[Lee Schierer]

Hi Lee -- thanks for replying -- for some reason I don't have permission to view those jpegs, although my account was "activated" yesterday. I get an error. Thanks!

You need to be a contributor to see photos posted on SMC. It costs a minimum of $6 per year. Cheaper than a cup of latte at Starbucks.

Bob, I just noted that this entire thread other than the recent comments is over 12 years old and has been resurrected several times. I suggest if you have any more questions regarding problems with your saw, that you start a new thread....

[Sam Force]

12 years!!! You might need a new calculator

[Lee Schierer]

12 years!!! You might need a new calculator

I definitely got my wires crossed somewhere.

[ROBERT SILVERSTEIN]

You need to be a contributor to see photos posted on SMC. It costs a minimum of $6 per year. Cheaper than a cup of latte at Starbucks.

Bob, I just noted that this entire thread other than the recent comments is over 12 years old and has been resurrected several times. I suggest if you have any more questions regarding problems with your saw, that you start a new thread....

Thanks, Lee -- I will become a contributor. Also, thank you for the suggestion about starting a new thread. Some forums prefer not to start new threads for "same topic" so I wasn't sure

[Tom Bender]

There should be no lubricant on the nut, spindle or washer. A toothbrush a rag and the right solvent will fix it. Dish soap should do it but since it is also a lubricant it will require sufficient rinsing.

[Lee Schierer]

After some additional thought and looking at the images supplied by Michael Hanley ( http://imgur.com/a/aymktx2), it would appear that the shoulder next to the flange nut is a bit wide. From where I sit, putting a thin kerf blade on that saw without the dished clamping washer between the nut and the blade would not allow the nut to properly apply pressure to the blade. Even with the dished washer in place, it appears that the shoulder may be too long. The nut may bottom out on the threads giving the indication that it is tight, without actually putting pressure on the blade.

As for Dado blades, it is common to not use the dished washer. However, if you use shims between the blades and chippers to get exact widths of cut, make sure your shims are not compressible. On a stacked dado it is a good idea to tighten the dado set and then bump the saw on and off quickly before retightening. Sometimes the chippers can drop down into the threads of the arbor shaft and bind when they are first assembled.

[Dan Raessler]

Just bought a used Dewalt 7491 job site saw, not knowing about this problem. Arbor nut came loose several times. Dewalt sent a replacement nut but it came loose, too (while ripping a 1/2" thick piece of pine!). Has anyone who has had this problem found a solution? FWIW, DeWalt says that as a second owner there is no warranty. Is there a way to find out how widespread this problem is? Thanks.

[Lee Schierer]

How are your tightening the arbor nut when you change blades? Are you using the flange washer that comes with the saw?

[Dan Raessler]

I put the wider side of the dome-shaped washer against the blade. The nut appears to be the same on both sides. I tighten by hand, then "snug" it a little tighter. I tightened the nut more than that once and it still came loose. Only has happened while cutting wood--not on shutdown, at least not so far. Thanks.

[Lee Schierer]

The shaft of the motor should be turning in the opposite direction from how you turn the nut to tighten. The sawing action should tend to tighten the nut not loosen it. I tighten by hand then hold the blade with my left hand and use the saw wrench to tighten the nut to a point just before it would slip my left handed grip on the blade. I've never had a blade loosen doing this for the past 40+ years

If your saw uses two wrenches then apply more torque to the nut.

[Dan Raessler]

Thank you for the suggestion. I will try that. I very lightly tightened the blade on my previous saw and it never worked its way loose--that is why this was such a shock. FWIW, I was using a thin kerf blade with a stiffener next to it the first time this happened. After removing the stiffener it happened several more times. I probably will try cutting some 1/2" plywood later this week (standing out of the path of the blade, just in case) and hope for the best. Again, thank you.

[Bryan Hall]

I had the same issue develop with that saw as well. I assumed I, or one of my crew members, had been overtightening it and caused damage to the threads. After 3-4 months of trying to fool with it and get a solution I gave up and just replaced it. I could have replaced the arbor I think, but since it's a work tool I just let it go.

[Lee Schierer]

FWIW, I was using a thin kerf blade with a stiffener next to it the first time this happened. After removing the stiffener it happened several more times. I probably will try cutting some 1/2" plywood later this week (standing out of the path of the blade, just in case) and hope for the best. Again, thank you.

Sometimes the arbor threads are cut too close to the fixed flange on the arbor and thin kerf blades or chippers in dado sets will drop down into the threads and bind when you are tightening the nut. As soon as the blade encounters resistance the blade will move and pop out of the threads, leaving the blade(s) loose on the arbor. I have a Craftsman table saw with a 1 Hp motor and I find that a good sharp full kerf blade works just as well and gives a better finish than the thin kerf blades. I no longer use any thin kerf blades. All my blades are Freud Industraial 60 tooth blades except for my Freud Glue Line ripping blade. Your 2+ Hp saw should easily handle full kerf blades.

[Dan Raessler]

I hate the thought of giving up on the saw. I will try a blade with a standard-width kerf. I think that that is what the previous owner had. I was disappointed at how much effort it took to remove his worn-out blade, though. Makes me assume he had the same problem and dealt with it by over-tightening the arbor nut. I also plan to call a number of DeWalt service centers to find out whether they have dealt with this problem. If I learn something from one of them I will post that information. Again, thank you for your thoughts about this and suggestions. Dan