Fitting joints

[Jim1611]

How tight should a tenon fit?
Thanks
Jim

[beenthere]

So it stays together with no glue... not tight, but not so it falls apart either.

Whatcha making, as the above may not "fit" the joint you speak of?

[razor]

Years ago i used to make my joints so tight i had to either pound or pull them together. I used to put wax on the tenons! But then i went to England to do some timber framing and was taught that a well cut joint should have some slop to it and leave the tight fit part to the housing (if any)and drawbore. In fact there was a least 1/8" of slop in some tenons.
I'm not that extreme now but if I can't slide a tenon in with little more than a gentle nudge then it's too tight. The tenons are cut with a gentle taper. A little sloppy to start but just right when she's home.

[Jim_Rogers]

1/8" gap between tenon and mortise is way too much.
A tapered tenon is fine as long as when it's seated there is no slop.

When you slide a tenon into a mortise it should do just that, slide in. It should not have to be pounded in. Pounding in a tenon means it's too big, and may cause the mortise timber to split. Your tenon should not act as a wedge to split the mortise timber.

The old saying used at the timber framing school, I visit frequently is "Perfect is close enough".....

Jim Rogers.

[Jim1611]

Thanks men. I am building an alcove in our house for a wood stove and want to frame the opening with timbers. Two vertical and one over the top and thought it would look nice to do that with timbers. I would need mortises on two corners. It's not structural at all but I want to make it right and it would be a good place for me to start learning.

[Dave Shepard]

I taper my tenons slightly from the end up to the peg hole. From there to the shoulder it is full dimension. If you layout accurately, and cut to the lines, you should have tight joints that slip together without forcing.