Thin metal wedges for door casing corners
A long time ago when I used to help another carpenter, he had some thin metal wedges that when drove into the outside corner slot (1/16" maybe) we cut into each side of the corners would literally pull the joint tight. It was so tight that we could actually build the casing for around a window at our shop, throw it in the truck, transport to the job, and install. Those joints would simply NOT open up without destroying something. I have not seen them in years, but when recently doing an addition to my parents house which was built in the '70s, there they were! Does anyone know about these, where to get them, the router bit we used, why are they not still used?