I have built several tables with intersecting mortises and tenons where I mitered the tenons in the leg/apron joint. In each case this was done to get the tenon length to the “1/2 to 2/3” the width of the leg rule of thumb. I now wonder if it is even necessary at all to intersect these mortises. Does the extra 3/8″ or so in the length of one face of each mitered tenon really add any appreciable strength to the joint, especially after removing the extra material from the leg to make the mortises intersect? I would add that these are hand chopped mortises where the intersection isn’t always super smooth and precise in the real world.
-Deke
Replies
Sorry, the extra 3/8" in length doesn't mean much out of context,
The dimensions of the stretcher and the leg, as well as the intended use are usually how one determines such things.
You do get the added glue surface along the long outer side of both parts. If you thought that one side that needs it more than the other I guess you could go full on one and short one. The miter gets you the "max" on both.
If strength is the concern, I would use an overlap tenon not a mitered tenon.
My question is not about which type of joint to use in a given situation. I am talking about, specifically, an intersecting, mitered, mortise and tenon vs. the same exact joint without intersecting. I understand that the mitered version would be theoretically stronger, but wonder if that would be significant in imperfect, real world, hand chopped conditions. Has anyone ever compared or even tested this? -Deke
I've never seen a test, or a mathematical figure given to the strength of mitered and unmitered joints. I just do it. It doesn't hurt, and takes an insignificant amount of time to accomplish.