How tight to make a joint?

[Nigel]

I've been experimenting with my woodrat and I find that after some practice I can make joints as tight or loose as I wish.

Although there is a certain satisfaction in making a really slick, precise and tightly fitting dry joint, I begin to suspect that things would be better if I left a little more room for some glue.

While all the test joints I have made seem to hold OK, with an aim of making furniture that lasts reasonably well I am concerned to get this right.

What's the word then, assembled guru's, on how tight is tight enough, or how much space is necessary for sufficient glue in a joint?

[Duane Bozarth]

...

Snug w/ a light tap for final drawdown on a large mortise...

More force required is too tight, a fit that goes "klunk" when it hits the shoulder is too loose...

[Swingman]

My general rule of thumb is just tight enough to put together and take apart by hand, but not so loose that it will fall apart by itself.

[LRod]

I hope I'm not the only one to make a smartass reply based on the subject line, but I was taught to make it tight enough that none of the leaves fall out once it's lit...if I'd ever rolled one, that is...one what, I don't know.

- - LRod

Master Woodbutcher and seasoned termite

Shamelessly whoring my website since 1999

[Phisherman]

[Nigel]

I'm sure I don't know either !

[Nigel]

This is what I was worrying about. This sounds like the best of both worlds then - a tight fitting dry joint is a pleasure to produce (in a wierd sort of way) and should hold well too!

I assume this is also glue independant? For now I'm using TiteBond ..

Thanks people,

Nigel.

[George]

Well, it's not all that you think. The word "snug" is best, I believe, in describing the dry fit. Water-soluble glues expand the fiber almost immediately, so don't dawdle over assembly.

Oh yes, the plastic will keep the area expanded as it solidifies, so you really can get by with a little less than a press fit.

[Tim Douglass]

Beat me to it.

Tim Douglass

[bridger]

you want them to slide smoothly together without needing to be driven and without slopping about.

[GerryG]

While I agree with all the posts, I'll add one item: the surfaces should be smooth. I can just a joint on the bandsaw that slides smoothly together without slop, but the rougher surface just won't be as strong unless the glue is sufficiently gap-filling and enough is applied.

Still and all, most well-made glue jo>>

[Dave Jackson]

[Mutt]

Brings back memories of 30 years ago when I could roll up a perfect bone with one Bugler paper (not that EZwider stuff, that was for "kids") in under 10 seconds. Although I gave up the reefer almost as many years ago, a buddy of mine smokes Bugler's and I rolled one up just as quick for him, better than he can, so you never lose the touch, I guess.

Mutt

[Lew Hodgett]

RE: Subject

Reminds me of the old one about how do you make a hormone?

Answer:

Don't pay her.

Lew

[John DeBoo]

Does one may need a clip or clamp to properly hold it during some part of the process? Damn, I don't remember... Got the munchies....gotta go....... Go Seahawks!

[John DeBoo]

Or step on her douche bag..............

[Tim Douglass]

I think that a clip of some sort would be considered part of *using* not *making*.

Right on!

Tim Douglass

[Tim Douglass]

Good point and one I hadn't thought of. How smooth *are* the mortises from a mortising machine? Maybe on a related thought, are mortises stronger with rounded corners (routed) or with square corners? Intuition would tell me that a rounded M&T would have fewer stress points and would therefore be stronger, but intuition is often wrong.

Tim Douglass

[George]

Maybe on a related thought, are mortises

M/T has shear strength based on the tenon depth and wood strength. Shape of corner unimportant. What's important is that the tenon should mate with the bottom of the of the mortise in the load direction. Can be loose as a goose up top.

Racking stress depends on a firm register of the shoulders of the tenoned member against the mortised member.

Unshouldered tenons should fit and bottom the mortise to take best advantage of the anti-racking available by having some resistance at right angles to the tenon itself.

[Nova]

This may refresh your memory... "bracelet assistant", right!

Novak Buffalo, NY - USA (Remove "SPAM" from email address to reply)