# Vibration in table saw



## VIFmike (Jul 21, 2012)

I have a vibration in my craftsman table saw. It makes the blade cut a wide cut until it smoothes out. I've checked and can't find anything loose. The belt looks fine and I just swapped blades between my scms and the table saw and its still there. I even bought a new blade. All my blades are Freud diablos. Help


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## WarnerConstInc. (Nov 25, 2008)

Start working backwards. Take off the blade and run, take off the belts and run, you will figure it out.


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## VIFmike (Jul 21, 2012)

I ran it with the blade off the shaft is smooth and straight. It also has no slack in the shaft. Bearing seems fine. Maybe I can take the mechanicals off of the top and see it better.


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## knotscott (Nov 8, 2007)

What model saw do you have?


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## GeorgeC (Jul 30, 2008)

If it is making a wider than normal cut the blade is obviously wobbling. You changed blades so that is not it.

That only leaves the entire motor moving on it's mount or the shaft not being solid in the motor.

Did this condition come on suddenly or gradually? How long after startup does it take for the vibration to go away?

It would not take much play in the motor shaft/armature to induce a small amount of wobble in the blade. That small amount may be very hard to detect with just your hand on the shaft. Just a very small movement of the motor in the mount would also be hard to detect.

George


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## willbess08 (Jul 5, 2012)

I ran into this same problem with my unisaw a month ago, I dont know if its comparable to your situation or not, but thought I would post. I took everything off, everything seemed smooth, had the motor gone thru, etc. I finally found the nut on the back of the shaft that goes from the blade thru the bearing and into the pully for the belts and it was an eighth of a turn loose. When I tightened that, she ran like a dream. The bearing/arbor didnt feel wobbly or run wobbly but that little bit of slack caused the vibration due to the tensions of the belt under load. hope this helps, I know how frustrating that can be, especially when its the only saw you have in the shop!


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## VIFmike (Jul 21, 2012)

The saw is a Craftsman #21833 with a Freud Diablo 40 tooth blade. 

The shaft and blade do not feel loose. I try to move it to see if it moves in any direction and it does not. The blade only has the vibration at the cutting edge. at the center it is not moving that I can see while its running. Also when it's on it vibrates and oscilates, meaning it has the vibration for a few seconds then it almost goes away then comes back and that oscilation is what bothers me. when it cuts thru a piece the cut is wide, then narrow then wide again as you go thru the wood and about 10" into a rip cut then it cuts straight. 

I have recently straightened the motor assembly to get the blade lined up with the fence. I loosened the 4 mounting screws and tightened them all back and it was fine after that.

It seemed to come on gradually. I do use the saw every day for lots of cuts. I have had it for almost a year.


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## toolguy1000 (Oct 4, 2012)

have the pulleys been checked for tightness?


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## Steve Neul (Sep 2, 2011)

Has anything happened recently to the saw. I remember one time a guy droping a sheet of plywood on a saw and letting it slide up against the blade. Not only did it damage the blade it bent one of the washers so any blades put on the saw wouldn't run true. When we changed the washer it fixed it. 

Another thing you might try is with the blade and washers off try running the saw and put a stick up to the shaft and see if the shaft is true. If it is running out of round you will feel it pulsating against the stick. It should be very smooth when you touch it. It's possible the arbor bearings are getting worn enough to run out of round but not enough to feel it wiggling the shaft.


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## VIFmike (Jul 21, 2012)

toolguy1000 said:


> have the pulleys been checked for tightness?



Cant' get close enough to them to see. the belt is tight.


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## VIFmike (Jul 21, 2012)

Steve Neul said:


> Has anything happened recently to the saw. I remember one time a guy droping a sheet of plywood on a saw and letting it slide up against the blade. Not only did it damage the blade it bent one of the washers so any blades put on the saw wouldn't run true. When we changed the washer it fixed it.
> 
> Another thing you might try is with the blade and washers off try running the saw and put a stick up to the shaft and see if the shaft is true. If it is running out of round you will feel it pulsating against the stick. It should be very smooth when you touch it. It's possible the arbor bearings are getting worn enough to run out of round but not enough to feel it wiggling the shaft.


Nothing has happened and I am the only one that uses it. I took the blade off and ran it but just checked it visually. I will do the stick thing.


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## toolguy1000 (Oct 4, 2012)

VIFmike said:


> Cant' get close enough to them to see. the belt is tight.


while the belt tension may be appropriate, a loose pulley may cause irregular motion as the pulley flops (i.e., starts shaking on the shaft as the shaft rotates) around on the shaft and begins ruining the key that fixes a pulley on it's shaft.


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## VIFmike (Jul 21, 2012)

I will have to unbolt the assembly from the deck and see what might be loose. When it runs the only place you can see the vibration is out at the outer edge of the blade. At the center it does not seem to have any variation from true. 

Maybe I could take a video of it.


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## woodnthings (Jan 24, 2009)

*try a new blade.*

Check that one for missing teeth. You can also rotate the blade on the shaft 90 degrees at a time and see if that makes any difference. I did that on my saw and found a "sweet spot" where the blade ran real smooth. Mark the shaft and loosen the blade turn it to 3 o'clock, then 6 and 9 and back and see what if any difference that makes. If nothing works it probably is a bent blade. I overheated one ripping some pressure treated wood and it wasn't the same afterward. ... nice Bosch blade too. :thumbdown:


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## woodnthings (Jan 24, 2009)

double post


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## VIFmike (Jul 21, 2012)

I swapped blades from my scms and it did not change. I also put in a new Freud diablo blade and it did not change.


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## toolguy1000 (Oct 4, 2012)

so now you know the problem is more than just a defective blade.


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## VIFmike (Jul 21, 2012)

toolguy1000 said:


> so now you know the problem is more than just a defective blade.


Yep, I am perplexed at what it might be. I pulled the back cover off and found the belt had jumped one groove off the edge. It's a multi groove belt. Maybe it has something to do with that. 

I think I should turn it upside down and unbolt the whole assembly and see wtf is wrong. 

I thought maybe a bearing but it doesn't feel loose at all. It must be a very small issue or it would probably vibrate more. I will try rotating the blade and see what happens. Maybe I got it in the wrong place somehow.


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## woodnthings (Jan 24, 2009)

*That's a hybrid*

http://search.yahoo.com/search?ei=utf-8&fr=ytff1-tyc7&p=craftsman%2021833%20table%20saw&type=

There have been vibration issue with some of them, mine's a 22124. It vibrates on shut down. 

Here's a thread about vibration on those and it has to do with athe spring tension or a loose pin or some such thing. It was a great mystery..... 
http://www.woodworkingtalk.com/f12/slow-modulated-vibrations-new-table-saw-craftsman-22114-a-18454/

See posts 37 and 43!


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## MORRIS76 (May 6, 2013)

VIFmike said:


> I have a vibration in my craftsman table saw. It makes the blade cut a wide cut until it smoothes out. I've checked and can't find anything loose. The belt looks fine and I just swapped blades between my scms and the table saw and its still there. I even bought a new blade. All my blades are Freud diablos. Help




Order a pair of machined pulleys and a link belt and thank me:yes:Your saw will thank me too


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## MORRIS76 (May 6, 2013)

Just curious.....did you solve the vibration problem with your saw?
Nosies want to know.


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