T&G cabinet door frames: tongue and panel dimensions

[Jim Becker]

The reason that I suggested keeping those tongues at full length is that the tenons are the entire non-end-grain glue surface that's going to be the strength of the frame, so other than adjusting for that "whisker" for fit, you maximize glue surface that way. For more strength, you'd need haunched tenons with traditional mortises in addition to the T&G coped edges.

[Warren Lake]

they are tongues not tennons, no mortise, its a slot or groove. Ive had this discussion with a young guy who owns a door company. He called his cope and stick doors mortise and tennon. Explained his cope and stick are Tongue and groove with a coped rail end. Got the deer in the headlight look. Joe here does cope and stick that is mortise and tennon with the larger cutters he uses.

For the tongue Mark think you mentioned 3/4" and while that is bigger than any of those cutter sets or door companies ive seen ive also seen one guy doing that who complained they were hard to assemble. Its because with that much material removal his rails and styles where the deeper tongue was run were bending in and under his .250 dimension making assembly more difficult. I dont think it helps gluing either as its going to push more away when the tongue is inserted being too tight.