Tenons..how loose?

[Robin Cruz]

for loose tenons being used in chair construction......how tight or loose should the tenons be? How do I judge the correctness of fit....easily side into mortise, friction fit and have to be hammered in, maybe about a paper thickness less as a way to judge a good fit? It still has to accept glue so I would think too tight would not be good for a strong glued joint.

Any ideas?

[Frank Drew]

Robin,

You want a snug slip fit, not so tight that you have to hammer it home when you test fit it, but not so loose it's sloppy -- white and yellow glues don't have much strength if the glue line is at all thick.

I know that might seem rather vague, but it's something you'll come to know pretty soon.

[Joe Scharle]

A general rule for all joints is:

Press in - Tap out

Joe

[Cliff Rohrabacher]

the word "lose" doesn't imply loose fit. It is speaking to the fact that the tenon is not part of either piece of wood being joined - - it is loose.

I guess the first loose tenon guy who named it thought they might be running lose all around his shop while he slept at night.

[Robin Cruz]

the word "lose" doesn't imply loose fit. It is speaking to the fact that the tenon is not part of either piece of wood being joined - - it is loose.

I guess the first loose tenon guy who named it thought they might be running lose all around his shop while he slept at night.
not sure what your saying.......loose tenon joints are obvious. Im asking for the tolerance of the joint. BTW its loose....not lose. A better definition then yours is per Webster: not rigidly fastened or securely attached.

[Peter Quinn]

Well, If the glue film on each adjoining face has to be ideally around .004" for PVA glue (the working number I was given for Tite Bond type glue) then I guess you would want the difference between your tennons and mortises to be about .008". I'd call that a friction fit personally, but I've had some semantical discussions about this before, and apparently not every one agrees on the terms. So, you should be able to slide the thing together dry with out a hammer, and it should not fall out on its own with out some help from you, again with out a hammer!

To me the fit for a loose tennon (by what ever name you call it) is no different then the fit for an integral tennon, or a dowel for that matter. OR, the stub tennon on a cope and stick set up, or......:eek:

[Jesse Cloud]

To me the fit for a loose tennon (by what ever name you call it) is no different then the fit for an integral tennon, or a dowel for that matter. OR, the stub tennon on a cope and stick set up, or......:eek:

Peter nailed it!

Having said that, I also make some loose tenon stock just a shade thinner (a few passes with some sandpaper) so that it will come out easily. I use this for dry fits before glueup.

It can be hard to remove a well fitting loose tenon.

[Alan Tolchinsky]

I agree that they should be snug when dry fitted but not tight. And don't use too much glue or else you'll have a mess. BTW since you are correcting other's spelling (poor form I think) remember sentences start with the first word capitalized and end with a period. This makes writing much more understandable and easy to read. :)

[Robin Cruz]

Well, If the glue film on each adjoining face has to be ideally around .004" for PVA glue (the working number I was given for Tite Bond type glue) then I guess you would want the difference between your tennons and mortises to be about .008". I'd call that a friction fit personally, but I've had some semantical discussions about this before, and apparently not every one agrees on the terms. So, you should be able to slide the thing together dry with out a hammer, and it should not fall out on its own with out some help from you, again with out a hammer!

To me the fit for a loose tennon (by what ever name you call it) is no different then the fit for an integral tennon, or a dowel for that matter. OR, the stub tennon on a cope and stick set up, or......:eek:
thats an easily understood and quantifiable approach. thanks! Sounds like my new drum sander will come in handy a few different ways.

[Doug Shepard]

I shoot for being able to push them in and pull them out by hand but with some effort. Dont waste any time once you get some glue in the mortises and things start swelling or you might have to pound it in and then the mashed end probably wont fit into the other mortise.

[John Thompson]

Snug fit.. press in.. tap out. All are good rules of thumb and I will add a touch looser in winter when humidity is down and wood has contracted.. and a touch tighter in summer when humidity is higher and wood has swelled.

Also to be considered IMO:
The species as some will expand and contract with moisture changes more than others.

You didn't mention where you are.. but here in Atlanta we have low humidity short winters and much humidity summers which will play a role in the final solution.

And I would factor in the inside humidity if the piece is in a kitchen or bath or other parts of the house where the humidity would be lower.

With all things considered.. then I know what is just right. :)

Good luck...

Sarge..