# cutting tenions with dado set



## Ronnie1a (May 24, 2009)

I am using knotty Alder 3/4" wood. My project calls for cutting several pieces with a grove 3/8 wide down both sides of each piece, in the middle of the edge which I have done without a problem. I am getting into trouble cutting a 3/8 tenion 1/4" long on the ends of each piece. The dado blade sometimes tears a chunck off the very edge of the wood as I finish the cut and this will show when I fit the piece into the grove of another piece. The finished product will be a frame with a panel in the middle.

I have tried a very slow cut but it doesn't prevent it. How can I prevent that tearout on the corner as I make the cut with a dado blade? 

Hope my description makes sense.


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## woodnthings (Jan 24, 2009)

*That's a common issue*

A simple solution is to use a "backer" when cutting the dado to prevent the tearout. :yes:


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## Al B Thayer (Dec 10, 2011)

woodnthings said:


> A simple solution is to use a "backer" when cutting the dado to prevent the tearout. :yes:


I agree. 

Are you sure the dado is sharp. You could also make score cuts with the table saw blade but it adds lime and work to the process. 

Al


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## ryan50hrl (Jun 30, 2012)

It's tearing out the grain on the back side....easiest solution is a backer block. If the dado requires more than one pass to get the length of the tennon, you can start at the shoulder and then move to the end...this helps. But really just using a backer is a super cheap easy solution...


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## Al B Thayer (Dec 10, 2011)

I here a double echo.

Al


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## ryan50hrl (Jun 30, 2012)

Al B Thayer said:


> I here a double echo.
> 
> Al



Oh? Where?


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## woodnthings (Jan 24, 2009)

woodnthings said:


> A simple solution is to *use a "backer"* when cutting the dado to prevent the tearout. :yes:





Al B Thayer said:


> *I agree. *
> 
> Al





ryan50hrl said:


> It's tearing out the grain on the back side....*easiest solution is a backer block*.





Al B Thayer said:


> I here a double echo.
> 
> Al



echo....echo....
I guess we all agree....for a change.


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## ryan50hrl (Jun 30, 2012)

Hell has frozen over.


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## Leo G (Oct 16, 2006)

I haven't used a dado to make a tenon in forever. I always use a blade. Put the wood vertical against the fence (or tenon jig for large runs) and make two cuts, then lay the wood down and cut the shoulders. You always keep the same side of the wood against the fence and you can be assured that all your tenons will be the same thickness even if the wood is varying thickness.


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## WarnerConstInc. (Nov 25, 2008)

Leo G said:


> I haven't used a dado to make a tenon in forever. I always use a blade. Put the wood vertical against the fence (or tenon jig for large runs) and make two cuts, then lay the wood down and cut the shoulders. You always keep the same side of the wood against the fence and you can be assured that all your tenons will be the same thickness even if the wood is varying thickness.


Meh, I skipped all that and went right to buying a tenoner.


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## ryan50hrl (Jun 30, 2012)

I use the delta tennoning jig 90% of the time....and actually prefer doing it that way.


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## Steve Neul (Sep 2, 2011)

A 1/4" tenon isn't very much. It's not much better than a butt joint. 

As far as the tear out, I make tenons all the time with a dado blade using both a table saw and a radial arm saw. Something sounds very wrong with the set you have.


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## Al B Thayer (Dec 10, 2011)

If you have the right router lift you can cut both mortise and tenon on the router table. Super fast without tear out.

Al


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## Al B Thayer (Dec 10, 2011)

Steve Neul said:


> A 1/4" tenon isn't very much. It's not much better than a butt joint.
> 
> As far as the tear out, I make tenons all the time with a dado blade using both a table saw and a radial arm saw. Something sounds very wrong with the set you have.


.... deleted my post.

Al


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## Ronnie1a (May 24, 2009)

The backer board worked well. Thank you, all, for your responses.


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## ryan50hrl (Jun 30, 2012)

Good to hear...it's always nice when there's a 25 cent solution to a problem.


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