# How snug should tenons be made



## BJODay (Jan 29, 2013)

I'm making a set of 3 nesting end tables. This is the first project I'm making with M&T joints. The first table fit together well on the dry fit.

On the second table, I was very careful and made the tenons snug to each corresponding mortise. I actually had to lean on them to test the fit. Well when I put it all together for a dry fit it seemed too tight. It was not square and there was no flex to make it square. I disassembled the table and sanded the tenons slightly with 100 grit paper. Then dry fit again. This time it went together easier and was square.

My questions is this, How tight do you make M&T joints? 
Squeeze it with lots of force?
Use a clamp to pull it tight?
Slip in with no slop?
A little slop to allow flexing to true it up during gluing?

I have one more set of M&T joints for the largest table. Any advice will be appreciated. I'm a little concerned. I don't want to have problems once I start slopping glue around.

Thanks
BJ


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## Smitty_Cabinetshop (Mar 26, 2011)

IMHO, it's between these two choices:

Use a clamp to pull it tight?
Slip in with no slop?

Lots of force not good 'cause you may break / split the stock either with fitting or with glue squeeze out that has no place to go. On the other end of the spectrum, hard to quantify 'a little slop.' The object is to have it true with no slop, of course, so if adding gets it square, after dry fit checks, so be it. Robert Wearing suggests sawing tenons that fit straight from the saw, as corrections after the fact are tougher than doing it right the first time. He taps with block and hammer when checking fit.


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## tefinn (Sep 23, 2011)

I was taught that they should be a nice friction fit. If there is slop you don't get good glue to wood bond. If too tight, you risk splitting the mortise by forcing the tenon into it.


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## rockindavan (Mar 8, 2011)

If you can slide it in with little force by hand, and pick up the tenon end and it stays together, you have just about a perfect fit. If you pull it back out and get a "plomp" sound, you nailed it. In reality it doesn't always work that way but too tight of fitting joints can bite you when glue up comes around.


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## mojapitt (Dec 31, 2011)

1+ on smitty comments


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## KnickKnack (Aug 20, 2008)

A great woodworker once told me…

"Here's how ya know if the joint's cut right. If ya gotta whack it with you hammer to get it closed, it's wrong. If ya whacking it with you hat and it closes, it's wrong. So don't use you hammer or you hat. Get it?"


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## lateralus819 (Mar 24, 2013)

If its too loose, take a plane and make a shaving and glue it on the tenon. Should help.


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## Loco (Aug 11, 2013)

Tight enough it takes 2 guys/no hammer.


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## BJODay (Jan 29, 2013)

Thanks for the tips. I think most of the tenons were snug "hand tight" joints. I had three that were very tight and I think these were the culprits that gave me trouble.

Smitty: yes adjusting tenons after cutting is difficult and an easy way to screw them up.

BJ


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## Kentuk55 (Sep 21, 2010)

Friction fit. (a little persuasion don't hurt) You gotta remember, glue will be added, so, you don't want them too tight to start. You should always, always, do a dry-fit of everything…..i.m.o.


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## suni123 (Oct 10, 2013)

Thanks for the tips. I think most of the tenons were snug "hand tight" joints. I had three that were very tight and I think these were the culprits that gave me trouble.


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## BJODay (Jan 29, 2013)

Larealus819,

I cut one a little too narrow. I used your trick and glued on a shaving from a block plane. It worked great.

Thanks for the tip.

BJ


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## Woodshingle (Oct 21, 2013)

No one mentioned that the sides of the mortise and the tenon need to be smooth all around. If not, the joint won't last no matter how tight it is.


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## Sigung (Nov 20, 2013)

Have you considered drawboring the joints?


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## BJODay (Jan 29, 2013)

Jerry,

Not on this project. That is something I would like to try in the future.

BJ


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## BinghamtonEd (Nov 30, 2011)

I use the same philosophy as rockindavan. I try to make mine so I can get them together without a hammer or clamps, and they stay together if I pick it up. The clamps pull everything tight and square while the glue dries, and can close up small gaps (1/32 or so).


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## Loren (May 30, 2008)

If you need a hammer to put it in, it's too tight. If you
can put it in with your hat, it's too loose.

If they are made too tight, it can be a trick to get 
dry-fitted assemblies apart without bruising the
tenon shoulders.

Modern glues do better job filling gaps than the traditional
glues.


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## SCOTSMAN (Aug 1, 2008)

why not wedge the tenons with a looser fit it looks nice and does a great job also Drill a hole near to the tenon shoulder and cut a groove up to meet the hole in the centre opf the tenon then when fitted and glued insert a small pre tried wedge into it like you find on a hammer or mallet I should say.Alistair


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## REO (Sep 20, 2012)

too tight and the glue gets stripped off the tenon as it is assembled if you glue the tenon. same goes for gluing the mortice or both for that matter. too loose and you are requiring the glue to take the load. different glues take different clearances to work properly. be sure to work the glue into the surface and give it a chance to wet before slamming the assembly together. if you used the "pick it up and it should stay together" with timber frame they would be to tight.lol. sounds to me like your on the right track anyway.


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## Holbs (Nov 4, 2012)

Mortise and tenon joint accuracy


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## Fuzzy (Jun 25, 2007)

The fit is a big part of the equation … how you get there is equally important … I was taught to NEVER glue a sanded surface .. only a cut one. Sanding forces debris into the pores and affects the overall joint strength. How much ??? I have no idea how to quantify the difference, but I can say that I personally want every shred of strength I can attain in my joints, and if that means using a plane or scraper rather than sandpaper, that is going to be my choice.


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