# Table Saw Safety



## lenh (Feb 27, 2009)

I think this is the best place to post this question.

I have a task where I need to cut a 3/4" x 1 7/8" deep dado. My idea is to cut the dado in 2 passes of about 3/8" wide. (the slot needs to be just shy of 3/4" I determined that the max depth of cut with my 8" dado set is 2 1/8". No problem there.

What I ran into is that the dado throat plate on my PM 66 will only let me raise the dado stack about 1 1/2" before the blade teeth come in contact with the front edge of the opening. It is easy enough to make a wooden throat plate to accommodate the width and depth. 

What has crossed my mind is if this throat plate limitation is by design. Is there some reason why I cannot or should not cut a dado to to maximum depth capability? 

The saw has plenty of power to make the cut. Actually a 3/8" x 1 7/8" cut is about the same as a 3/4" x 1" cut. Besides with the blade raised that high the cutting angle is steeper and should cut easier. 

It just bugs me that the throat plate will not let me raise the dado stack to the maximum height.

I haven't tried anything yet. Maybe tomorrow I'll bite the bullet and see what happens. Right off I cannot think of anything bad happening.

Any thoughts? Anybody done this?


Len


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## Cherryville Chuck (Sep 28, 2010)

I've never made one that deep but if nothing is rubbing under the table I don't see why a different plate won't solve the problem. Maybe the maker never foresaw anyone wanting to max out the depth of their dado or maybe that is the maxed out length of a 6" set.


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## lenh (Feb 27, 2009)

Cherryville Chuck said:


> I've never made one that deep but if nothing is rubbing under the table I don't see why a different plate won't solve the problem. Maybe the maker never foresaw anyone wanting to max out the depth of their dado or maybe that is the maxed out length of a 6" set.


Thanks Charles, Agree, I'm probably over thinking this. I never thought about the throat plate being for a 6" set. I suspect you are right. Tomorrow will tell.

Len


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## Bricknhank (Dec 28, 2013)

lenh said:


> Thanks Charles, Agree, I'm probably over thinking this. I never thought about the throat plate being for a 6" set. I suspect you are right. Tomorrow will tell.
> 
> Len


I agree with C-Chuck. I cant recall making a dado that deep eith but why not make your own throat plate to accomidate your needs.


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## 64 ford (Apr 21, 2013)

Len
I've got a PM 66 in the shop when I go out I'll have to check mine.
Dennis


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## GregLittleWoodworks (Dec 9, 2014)

I agree about making your dado plate for this purpose. Save it afterwards because if you throw it away you will need it again...don't ask me how I know this...


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## MikeMa (Jul 27, 2006)

That is a crazy deep dado. To be honest, I don't think I would attempt this with a stacked dado blade at all, but rather my normal blade and move the fence over for each cut. 

I think it is also important to ask, WHY do you need a 1 7/8" deep dado? Getting another work piece to seat fully into that dado is going to be difficult, and you will never get it back out. I would seriously look at the design of the project to determine if you really need that deep of a dado.


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## lenh (Feb 27, 2009)

NiceG316 said:


> That is a crazy deep dado. To be honest, I don't think I would attempt this with a stacked dado blade at all, but rather my normal blade and move the fence over for each cut.
> 
> I think it is also important to ask, WHY do you need a 1 7/8" deep dado? Getting another work piece to seat fully into that dado is going to be difficult, and you will never get it back out. I would seriously look at the design of the project to determine if you really need that deep of a dado.


Mike, the attached will give you more of an idea of what is happening. The first bench I made I used a normal blade and moved the fence for each cut. But now I have to make 5 of these at once. That's 40 of these dado. Quite tedious. This design makes for an incredibly strong joint.


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## lenh (Feb 27, 2009)

I made up a zero clearance insert today. Cranked the dado blade through it to about a 2" height. Cut like butter. I am not sure why I was so hesitant to try this. Much ado about nothing.

Sorry for the distraction.

Len


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## jw2170 (Jan 24, 2008)

Glad to see that you were able to solve the problem, Len.

BTW, shouldn't the blades be offset so that the teeth are not touching?


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## lenh (Feb 27, 2009)

Of course, Jim. Hard to tell from the pic but the chipper between the two outside blades is not touching any teeth. Close though. Probably could have been spaced more to the center.


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