# What is this joint called and how would you make it?



## ssbothwell

This joint is really common in stretcher bars for canvas paintings. I'm having trouble working out how to the joint is made. I guess its a variation on a bridle joint.










its not clear in this photo but one of the faces is cut to a slight bevel (usually between 6 and 12 degrees).


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## JayT

I believe it is a mitered bridle joint.

Edit: I stand corrected. Here it is shown as a mitered double bridle joint.


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## dbhost

I am pretty sure that joint is called a "Folded Miter Joint". And while I have never made (or personally seen one up close and persona), I do believe either Shopnotes, or Wood Magazine a while back had a HOWTO article on those… Looks like a very strong, but somewhat difficult to make joint…


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## bandit571

Think more along the lines of a mitered half lap joint. Then cut out about half of each lap. Cut the slot for the lap to go into the corner. Lay out the miter first, but only a quarter of the way down. Each lap is also a quarter of the thickness. Miter=1/4, lap=1/4,slot= 1/4, and the other miter = 1/4 of the board's thickness. be sure to mark where each part goes, THEN cut with a saw.


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## patron

after the joint itself is done
then do the face bevel
as you will need the parts to be square 
for the joint themselves


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## steve_in_ohio

here is something very similar that shows you how to make it


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## bigblockyeti

I agree with the first post of it being a mitered double bridle joint. I would make it using a tenoning jig on the tablesaw.


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## Grumpymike

I've heard it called as Jay T says a "Mitered Bridle joint", and as someone said a "Double Miter Bridal".

A half lap would be one piece cut half way through on a 45 and the other piece the reciprocal.

A bridal joint is one piece with two sides (think open ended mortise) and the other is like a tenon, and slides into the mortise.

So, with all that being said, It's a "Mitered Double Bridal Joint" That's my story and I'm sticking to it …


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## ssbothwell

whoa, thanks for all the information! this just about covers it. i'll have to play around with my tenon jig and see if i can figure it out.

these joints get mass produced on an industrial scale for all the stretcher bars sold at every art store in the world so there must be a pretty simple way of cutting it.


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## Grumpymike

Called an old high school chum that worked in a frame factory till he retired. He says that they made the Double Bridle miters on a 'shaper' with multiple sets of heads … (As you know a shaper is like a giant router).

I would really like to see how you do on this scary looking joint … in the mean time I will be playing in my shop to see what I can do.


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## Alvinstan

The real name of this joint is MITRE FACED BRIDLE JOINT…actually i was been given this joint as a project in school..
Yet to construct it…


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## MrRon

I would cut the mortise and tenon first; then cut the miter, 1/4 down on one side ; then 1/2 down on the other side.


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## Unknowncraftsman

That's one heck of a school to give you a joint for a project


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## MSquared

I went to a high school where joints were part of the "Unofficial Curriculum", as decided by the Student Body. Her name was Maryanne!


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## ColonelTravis

I call it: glue-a-simple-miter-and-add-a-spline-instead-of-this-crap joint.
But that's just me.


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## Delete

Your right ssbothwell it is a bridle joint but more specifically it is called a "canvas-stretcher joint" The slite bevels (angles) are to slip in wedges to stretch the canvas. "Good Wood Joints" published by Collins in 1995 has a full page outlining how to cut them with illustrations. The frame was assembled without glue and the canvas stretched over it for the painter, as the humidity changed you could drive in wedges to keep the canvas tight.

I guess you could call them "miter faced Double bridal joints" ha, ha.


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## Unknowncraftsman

That's a nice joint for anyone wanting to improve their skills. 
Since it's four corners you will learn the importance of cutting,facing and planing you boards. Even a little twist will show in the end.
Then there's the accurate layout of the parts lengths with the miters and grooves.
I like these kind of challenges.


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## MSquared

Pardon my ignorance. I'm new to this. Just absorbing all the info I can from the always very generous LJr's. Aside from it's actual name would you call these reverse, upside down, mirror images of each other? What has me confused is that it seems that a lap joint or better, a 45 deg. mortise and tenon would be as strong.


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## Delete

Chapter 5 in the book "Good Wood Joints" is 6 pages long and covers bridle joints. 4 different joints are listed and included is information on how to cut each joint. To avoid copying complete pages I made up a page with just the "Canvas-Stretcher Joint" and description. This joint was designed for one purpose only it seems, but that shouldn't stop anyone from using it for other purposes if it appeals to the builder.


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## MSquared

I suppose the practical function is to allow for expansion and contraction for the gesso'd canvases? My son works at a local craft store and his buddy is the framing guy. Gotta run down and take a look.


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## Sylvain

Look at this Paul Sellers' video

Although in this video it is mitered only on one side (which is enough for many applications)

The principle would be the same for the double sided one.

One can make the joint with four squared boards and plane away the 6 to 12° relief after on each piece before final assembly.


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