# How tight should a joint be?



## Joel_B (Aug 14, 2014)

I am making joints using half laps surrounding a 2X3 DF.
The joint was too tight so I made some adjustments and now it is slightly loose.
Will the glue make up for the looseness? How loose can it be before it becomes a problem?
BTW I did these joints in three steps, First I made multiple vertical cuts on the TS.
Then removed most of the waste using a chisel and mallet, then cut to final depth on my router table.
I have done this way on other projects too except I used a miter saw and set the depth stop but the TS is much better.
Its a lot of work and time consuming so I think I should get some Dado blades.
I once asked my brother in law who is a carpenter if he had a Dado blade I could borrow and he told me they are dangerous and basically would not loan it to me which I don't have a problem with. But if used correctly are they any more dangerous than other shop equipment?

Thanks


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## wapakfred (Jul 29, 2011)

The Leigh jig folks say that .005" is about the right fit for an M&T joint, which is what you made with your 1/2 laps. But generally speaking, glue (except epoxy) is not a very good gap filler. Some folks think that the dry powder glues (the UF formula "plastic resin" glues) will fill gaps, and they are probably better than the PVA, but still not good. But just looking at that joint, I'd say you are good to go and don't worry about it too much. As for the dado set comments, well, he's your BIL so I'll tone this down: the dado set is no more dangerous than any other saw blade on your table saw…they can all do serious damage when misused. But with the same cautions, they are fine for use. I'd say your BIL had a (well, never mind).


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## Iguana (Jun 22, 2011)

Joel,

A good test for tightness is a piece of paper. If you can fit one or two slips in the joint, it is OK. At three pieces, it is starting to get a little loose.


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## groland (Jan 21, 2009)

When I got a tenon a little too small for the mortise, I just glued some veneer onto the tenon cheeks and re-fitted the joint. This worked well for me.

George


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## Rick Dennington (Aug 27, 2009)

Not too loose…..Not too tight…..Just right will do the trick…!!!!!!!!!!


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## AandCstyle (Mar 21, 2012)

If the tenon falls out of the mortise, it is too loose. If you need a mallet to drive the tenon into the mortise it is too tight. If it goes together with hand pressure it is just right.


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## TheWoodenOyster (Feb 6, 2013)

I shudder to think about some of my joints over the years. I wish I could say that all of my joints were slip fits, but the truth is that they aren't. None of my joints have ever fallen apart. I think the guys above are correct. A hand pressure slip together fit is perfect. Hard to attain though. That is one of the reasons why tools like handplanes are priceless. No other tool sneaks up on fits like a plane does. That said, get it as close as you can and if you need to do things like add a veneer strip, there is no shame in that. I bet 99% of projects out there, even from the pros, have little "fixes" throughout. Nobody is perfect. I believe it is Saint Sam Maloof that personally said he only ever made one perfect chair. I may have made that up, but it is probably true anyway…


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## jmartel (Jul 6, 2012)

> If the tenon falls out of the mortise, it is too loose. If you need a mallet to drive the tenon into the mortise it is too tight. If it goes together with hand pressure it is just right.
> 
> - AandCstyle


This. And you should be able to hold the joint up in the air without one of the parts falling off.


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## skatefriday (May 5, 2014)

> If the tenon falls out of the mortise, it is too loose. If you need a mallet to drive the tenon into the mortise it is too tight. If it goes together with hand pressure it is just right.
> 
> - AandCstyle
> 
> ...


And therein lies the skill. Anyone can run a board through a saw. Getting
parts to fit like that is not easy.


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## AandCstyle (Mar 21, 2012)

> And therein lies the skill. Anyone can run a board through a saw. Getting
> parts to fit like that is not easy.
> - skatefriday


That is why God created shoulder planes.


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