# Tongue and Groove width



## nrudnick (May 16, 2017)

I have recently purchased a Freud Tongue and Groove router bit set. The bit set has a chart which shows how to achieve certain tongue and groove width by using the provided spacers. I have read that you are supposed to center the tongue on the board but I can’t find any information that tells me if my stock is ¾ inch, what size should my tongue and groove be. Is there a chart or some other method that I can use to determine how wide my tongue and groove should be for 3/4 inch stock or any other size stock?


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## woodknots (Mar 7, 2012)

Neal, I don't know of an actual chart, but generally speaking the tongue should be 1/3 of the material you are using, so for a 3/4" board, the tongue should be about 1/4".

BTW, welcome to the forum


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## Nickp (Dec 4, 2012)

Neal...welcome to the forum...

As Vince responded, 1/3 of the width is a good rule of thumb or as required by your application or as dictated by the groove bit.

BTW...depending on the direction of the grain of the cuts and the application you are T&G'ing for, it could be possible that you might create a weak joint. For example, if you were T&G'ing for a table breadboard, you could be creating a weak joint on the long grain side.

One thing you might consider, for those joints needing lots of strength, would be to use a spline instead. You would cut a slot on both sides and use a floating spline essentially doing the same thing as a T&G except you would be able to put in a spline with grain perpendicular to the slots...mucho stronger... This also saves you some wood...the amount you would have cut off creating the tongue...

This is offered as an option...there are members who have been more than satisfied with T&G and others who are equally satisfied with just gluing the edges together...lots of experiences available on the forum using all these options...


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## Cherryville Chuck (Sep 28, 2010)

HI Neal and welcome. I also prefer splines to T & G. Splines lose no wood. T & G loses at least 1/4" . A spline is a free floating tongue in a double groove joint.


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## Stick486 (Jan 4, 2013)

what Cherryville and Nick said...

.


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## Stick486 (Jan 4, 2013)

sorry about the image posting failure...
just can't seem to get them to take...


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## Stick486 (Jan 4, 2013)

another try...

.


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## Stick486 (Jan 4, 2013)

try here to see the the attached pictures..

View Stick486's Uploads...


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## oldhudson49 (Feb 6, 2017)

The "1/3 rule" mentioned above, is what I've always followed....and welcome to the forum.


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## Shop guy (Nov 22, 2012)

Welcome to the forum, Neal. Go with the spline.


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## Nickp (Dec 4, 2012)

Stick486 said:


> sorry about the image posting failure...
> just can't seem to get them to take...


It worked...images show...


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## Cherryville Chuck (Sep 28, 2010)

One thing that hasn't been mentioned yet is when you are machining T & G or grooves splines you must be sure to work from one face on all boards. If you are making flooring it should be the back side that you register against the machine. If you were going to use them for something like the back panel of a hutch then you would register against the faces.


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## nrudnick (May 16, 2017)

*Thank you*

Thank you very much for all the great advice


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