# Weight of Dado Blade Or Vibration Is Causing Blade To Lower During The Cut



## JIMMIEM (Apr 4, 2010)

I'm making some tenons on my table saw using a Dado Blade and Miter Gauge. My saw is a Craftsman Contractor Model and the Dado blade is an 8 inch Oshlun. I'm cutting the tenons on 3/4" X 3/4" Red Oak. The tenons will be 3/4" long. I was doing some test cuts and realized that the tenons were too thick because the blade was lowering. I could actually see the blade lower a bit....vibration or weight(?). I have the Dado width set to a little over 3/4" by installing 6 chippers in addition to the 2 outside blades. I'm going to remove most of the chippers to reduce the weight and do each tenon in a few passes. I could do it with just 1 blade but this would take a while.....I have 10 tenons to cut.
Anybody have this happen? I can't think of a way to prevent this blade from lowering on its own other than to reduce the weight.


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## DaninVan (Jan 1, 2012)

Doesn't the ht. crank have a compression knob, or other means of locking in the ht. adjustment?


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## Stick486 (Jan 4, 2013)

look to your locking mechanism on the blade adjustment...


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## JIMMIEM (Apr 4, 2010)

The only locking mechanism on this saw is to lock in the blade tilt. There is nothing to lock in the blade height. Maybe there is wear in the blade elevation screw teeth? OR, I had added grease fittings to make the blade raising and lowering really easy.....maybe this allows the blade to lower itself with minimal downward pressure on the blade during dadoing?


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## Herb Stoops (Aug 28, 2012)

Try locking the tilt mechanism, it might be a combination tilt /height lock. Does the locking hand wheel move?
My Bosch 4100 contractor saw only has one lock on the tilt, never had the blade elevation move with a dado running. I keep the single lock engaged after adjustments of any kind.
Herb


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## RainMan 2.0 (May 6, 2014)

It may help if they knew the model


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## JIMMIEM (Apr 4, 2010)

RainMan 2.0 said:


> It may help if they knew the model


Craftsman 113.298240


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## JIMMIEM (Apr 4, 2010)

Herb Stoops said:


> Try locking the tilt mechanism, it might be a combination tilt /height lock. Does the locking hand wheel move?
> My Bosch 4100 contractor saw only has one lock on the tilt, never had the blade elevation move with a dado running. I keep the single lock engaged after adjustments of any kind.
> Herb


The tilt mechanism is locked....it doesn't move on its own. 

Maybe I'll just cut the tenon shoulders on the table saw and finish them on the router table.


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## DaninVan (Jan 1, 2012)

*New Saw In Future*



JIMMIEM said:


> Craftsman 113.298240


Sears | Craftsman - Publication Reprints - 113.298142 / 113.298032 / 113.298240 10" Table Saw Instructions, Parts List | VintageMachinery.org
Pg 21. No locking mechanism. Very strange.


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## Stick486 (Jan 4, 2013)

> Pg 21. No locking mechanism. Very strange.


yup...
the grease isn't helping either...


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## Herb Stoops (Aug 28, 2012)

After looking at the manual, I see where the tilt lock just locks the forward trunion on the tilt mechanism. The shaft for the elevation doesn't lock.
Must have done too good a job lubricating. Maybe there is a way you can make something to prevent the elevating wheel from rotating once it is set for the correct cut height. Some kind of clamp with a thumb knob you loosen to raise the blade then tighten to hold that wheel from turning.
Herb


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## Shop guy (Nov 22, 2012)

That is a terrible design flaw. Surely there is someway to fabricate a locking mechanism.


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## Herb Stoops (Aug 28, 2012)

It will take a little thinking ,because you have to allow the blade elevation shaft and wheel to move when the blade is rotated on an angle to cut a bevel.

Maybe an arm with a hole in one end cut for a clamping collar, and a slot in the handle to slide on a stud with a thumb nut to loosen and tighten down to hold in position.

Herb


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## Multiwood (Feb 24, 2013)

Jim if your getting vibration you might want to check your blades to see if you have any carbide teeth missing. I have the same
dato blades and I noticed yesterday that I have 3 carbide teeth missing on one blade.


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## DonkeyHody (Jan 22, 2015)

This is obviously a dangerously unsafe situation. (Yes, I know I redundantly said it twice.) Perfect excuse to buy a new saw.


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## old Steve (Feb 3, 2018)

My small Delta saw has always done the same thing with a dado blade...I usually have to put a clamp on the blade raising/lowering knob to hold the height position.


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## JIMMIEM (Apr 4, 2010)

Stick486 said:


> yup...
> the grease isn't helping either...


On a positive note the grease does make it real easy to raise and lower the blade.


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## JIMMIEM (Apr 4, 2010)

DonkeyHody said:


> This is obviously a dangerously unsafe situation. (Yes, I know I redundantly said it twice.) Perfect excuse to buy a new saw.


I bought this saw when Jimmy Carter was in the White House. Unfortunately a new table saw isn't in the budget right now.


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## JIMMIEM (Apr 4, 2010)

Knot working said:


> Jim if your getting vibration you might want to check your blades to see if you have any carbide teeth missing. I have the same
> dato blades and I noticed yesterday that I have 3 carbide teeth missing on one blade.


All the teeth are present. This dado set isn't recommended for and underpowered saw, which mine is. But, unfortunately I own it and it has worked well when it stayed put.
I'll see if I can rig up something to lock the blade height.


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## JIMMIEM (Apr 4, 2010)

Herb Stoops said:


> It will take a little thinking ,because you have to allow the blade elevation shaft and wheel to move when the blade is rotated on an angle to cut a bevel.
> 
> Maybe an arm with a hole in one end cut for a clamping collar, and a slot in the handle to slide on a stud with a thumb nut to loosen and tighten down to hold in position.
> 
> Herb


Thank You......I'll see what I can figure out.


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## Stick486 (Jan 4, 2013)

JIMMIEM said:


> On a positive note the grease does make it real easy to raise and lower the blade.


where have you been the last several years...
and dry lube will work even better.. (I like TriFlow)
grease and WD collect cud by the bucket full especially under the saw...


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## DesertRatTom (Jul 3, 2012)

It probably has an old drive belt, which might contribute to vibration. You might try changing it out for a a flexible link belt. You buy a length and then assemble it to exact length. I also think the lubrication is a big factor. My Laguna TS doesn't have a height lock and it is rock steady. The Laguna TS takes a slight effort to crank up but has a large, heavy wheel that reduces the effort needed to turn it. I think I'd also clean out the grease, particularly if the slipping increased or began after adding the grease fittings. Grease and TS mechanical parts don't mix well.


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## Stick486 (Jan 4, 2013)

often those belts treat the symptom and not the cause...
best to look into the cause of the vibration 1st...
if it's and old belt that is causing vibration a new belt will fix that and be way cheaper too...


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## tomp913 (Mar 7, 2014)

Don't know if it makes a difference, but the Dado listed under "Recommended Accessories" in the manual above is only 7" diameter - that might make a difference.


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## Stick486 (Jan 4, 2013)

tomp913 said:


> Don't know if it makes a difference, but the Dado listed under "Recommended Accessories" in the manual above is only 7" diameter - that might make a difference.


so would a 6'' be better still...


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## JIMMIEM (Apr 4, 2010)

Stick486 said:


> where have you been the last several years...
> and dry lube will work even better.. (I like TriFlow)
> grease and WD collect cud by the bucket full especially under the saw...


The grease is inside the trunion housing. The owner of InLine Industries sent me a video on how to install grease fittings. I installed the grease fittings about 10 years ago. A couple of years ago I had to replace the arbor bearing which required removing the trunion. The grease inside the trunion was free of saw dust.
I have a link belt. 
I saw some recommendations to raise the blade to final position rather than lowering the blade into final position. I'll also check all fasteners on the underside of the saw. Somebody also recommended hanging a vise grip on the blade elevation crank to give it some weight to prevent it from moving from vibration.


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## JIMMIEM (Apr 4, 2010)

Stick486 said:


> so would a 6'' be better still...


The manufacturer's literature did not recommend the 8" dado set for an underpowered saw. Mine is only 1 hp.


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## Stick486 (Jan 4, 2013)

JIMMIEM said:


> The grease is inside the trunion housing. The owner of InLine Industries sent me a video on how to install grease fittings. I installed the grease fittings about 10 years ago. A couple of years ago I had to replace the arbor bearing which required removing the trunion. The grease inside the trunion was free of saw dust.
> I have a link belt.
> I saw some recommendations to raise the blade to final position rather than lowering the blade into final position. I'll also check all fasteners on the underside of the saw. Somebody also recommended hanging a vise grip on the blade elevation crank to give it some weight to prevent it from moving from vibration.


my bad...
carry on...


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## Cherryville Chuck (Sep 28, 2010)

Drill a hole somewhere near the hand wheel roughly level with it. Put a bolt i the hole that has at least 1/2" of unthreaded shoulder on it. Double nut the threaded portion so that the unthreaded portion stands out from the saw. Attach a bungee strap from the hand wheel to the bolt once adjusted. The tension on the bungee strap should be enough to hold it in place. That's about as simple a fix as I can think of. Easy and quick to attach and easy and quick to unattach.


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## DesertRatTom (Jul 3, 2012)

Oh well, we tried.


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