Tightening blade and bit nuts

[Doug Jones]

This is probably a question I should of asked about a year ago. But I just thought of it today as I was putting in my dado blade. When changing blades in your saw or changing bits in your router how tight do you turn the nut? Do you just snug it or just tighten it, or do you hammer it on very tight? I myself put quite a bit pressure behind the nut. I don't want the thing to come off after me. But I am also the guy that thinks "just a little more" should be about right (if one is good two must be better).

[Bruce Page]

Doug, I’m usually a "just a little more" type of guy too but with the arbor nut in the TS, I finally learned that “snug” is all you really need and it makes blade removal sooo much easier. For router bits, I go for “firmly”.

[Jason Roehl]

As an aviation tech friend of mine put it--"crank it till it smokes, then back it off a quarter-turn" :D

Basically, I just put everything on pretty firmly and have never had any problems getting them back off.

[Dave Anderson NH]

I take the individual dado blades in the set and push them tight against each other by hand. After putting on the collar and the nut I snug up hand tight and then go another quarter turn or so. Remember that the nut tightens in the opposite direction of the dado blades' rotation. This means that the rotation keeps the nut tight for you. It can't loosen or come off since saw rotation tightens it for you. Trying to remove an overtightened nut on an arbor is sometimes very difficult if you overtighten. Remeber the nut must be snug, not cranked on by the Hulk.

[Jim Becker]

Saw blades only need the arbor nut snugged up...they will not come off due to the rotation of the blade and may actually get tighter with use. No need to "crank it" and in some cases, it could distort the blade if there is any problem with the arbor or arbor washer.

Router bits need to be tight so that they don't slip in/out of the collet from friction.

[Jim DeLaney]

Saw blades only need the arbor nut snugged up...they will not come off due to the rotation of the blade and may actually get tighter with use. No need to "crank it" and in some cases, it could distort the blade if there is any problem with the arbor or arbor washer.

Router bits need to be tight so that they don't slip in/out of the collet from friction.


Agree completely. Maybe an eighth of a turn beyond finger-tight on the table saw is all that's neded.

For router bits, though, make sure they're very snugly tightened.

[Paul Geer]

"Snug" didn't seem tight enough,

"Hammer it" and "Where did I put that cheater bar" was a little extreme,

so...


Firmly it is! :D

[Byron Trantham]

Snug will do it. I have played with this issue in the past and after someone pointed out the rotation/tightening relationship I always figured tighter is better. Not so. I would be willing to bet, but I have not tried it, that you can put it on hand tight, fire the saw and find out that the nut actually tightened itself. Anyway this is one of those situations that tighter is not necessarily better. Now router bits.......

[Glen Smith]

I go with snug, maybe a 1/4 turn with the wrench past finger tight.



Snug will do it. I have played with this issue in the past and after someone pointed out the rotation/tightening relationship I always figured tighter is better. Not so. I would be willing to bet, but I have not tried it, that you can put it on hand tight, fire the saw and find out that the nut actually tightened itself. Anyway this is one of those situations that tighter is not necessarily better. Now router bits.......

I'm not sure where finger tight starts, but if you don't get it far engouh it can be exciting! I was once using a saw in the craft center at NC State - only the lab assistant was allowed to change blades. I requested a blade change and when it was done, went to use the saw. Turned it on and realized that it sounded very strange. Shut the saw off and the blade kept going for a good 3 or 4 minutes. The labbie hadn't tightened the arbor nut enough.

I stood well away from the saw, 90 degrees to the blade till it stopped! Not an experience that I want to repeat.

Glen Smith

[Howard Acheson]

There are multiple answers to this question.

For tablesaw, miter saw and RAS blades, snug at best is the answer. When you tighten a blade too tight, you actually distort the plate and the blade will not cut as well. I just hold the blade between my fingers and tighten until my fingers slip on the blade.

For dado's, they should be somewhat tighter.

Both sawblades and dado sets tighten as they revolve.

Router bits should be very tight as the only thing that keeps them from slipping is the friction from a tight collet.

[Jim Baker]

I'll have to admit to being a cheater bar kind of guy. My wife refuses to change blades/bits in anything any more because I get them so tight that she can't begin to loosen them. Also, I'd hate to say how many bolts and screws I've snapped off from overtightening them.

[Kevin Gerstenecker]

I am a Snuggie guy! (Ever have a good Snuggie?........the kids today call them a Wedgie!) :D Anyway, I just Snug my Saw Blades......like others made mention of, they won't come loose because of Rotational Direction. Router Bits get a bit more Snug-ness. The most important thing for Router Collet is to make sure they are clean, along with the bit shank. I have found when I have a Router Bit come loose, it was because the collet was dirty, or the Bit Shank was not clean. It works for me! ;)