Picture frames have some of the most common yet weakest joints in woodworking. In Episode 3 of my Join It Series, I breakdown the “Sliding Dovetail Miter Joint” so you can see that miter joints are not weak when used in this manner.
First start with dimensional lumber cut to your specs. Then miter them using a compound miter saw or a table saw using a miter gauge.
Now set up the router with dovetail bit, preferably 1/2” shank to prevent chatter. The angle of the bit is not really anything important.
You should start with the mortise, which is easier to match a dovetail to, rather than the other way around. Set the fence so that it passes through the center of the stock, but to ensure that it is centered, you will need to flip it end for end and run it through again. This will surely center the mortise.
Now, run the stock over the bit on each side to form the tail. Be patient and sneak up on this thickness. You go to far and the tail will be too loose and your joint will fail.
You can see that we have a tongue for the adjacent mortise which we have trimmed so that it will be flush with the side of the adjacent piece. They should slide together smoothly yet snugly.
There should be no gaps so filler should not be needed unless you had chip out.
Using a filler tail, you can cover up the gaping hole left from the mortise cut out. I just cut this from another piece that I made for this very reason (planning ahead).
Thanks for reading and watching. I hope to catch you on the next join it build. Don’t forget to comment and subscribe to my newsletter.