Old beginner and tenons on cabinet door

[Aaron Rosenthal]

Years ago, I was given a load of used (shaped, finished etc) Oak in no particular grain configuration . I put it up over the rafters of my garage while I tried to make a living.
Semi inspired, 3 years ago I took a bunch of like-thickend pieces down (none wider than 2 1/2" including bullnoses), and began to edge-joint and glue them into panels. Project stopped in the winter, but I'm determined to finish this summer.
I dadoed the fixed shelves and base into the sides, etc., added my fixed stiles and pegged them; Today I added the 1/4" panel for the back.
I've done small stuff and repairs, but I've never had to make a door for a cabinet this size.
The door will be 38 3/4" tall with 3"x3/4" rails and 2 3/4" stiles.
This door will be heavy - I expect to use heavy Brass hinges for the door. I haven't decided if I'll machine more Oak for the insert or buy a nice piece of Plywood.
My concern is with the placement of the tenons.
I can size the thickness of the tenons, but my sense is to use a long tenon like 1 1/2" deep, AND peg it, with a tenon height of 1 1/4".
For a previous repair project I bought a dedicated mortiser, so that's not an issue.
To those of you who actually know what you're doing (not like me), are my tenons oversized or just adequate?

[Rod Sheridan]

Hi Aaron, if you use a plywood panel (my choice) you can use 3/8" deep stub tenons the same thickness as the panel and glue the panel in.

Even if you don't glue the panel short tenons will be fine for a light door like that.

If you want you could always make 1 1/2" deep M&T joints....................Regards, Rod.

[John TenEyck]

Typically, tenons are 1/3 the thickness of your stock, so if you are using 3/4" stock for the doors then they would be 1/4" thick. I use 3/8" tenons a lot now with 3/4" stock because I cut the mortises with a router so I don't have to worry about blowout like you do when cutting them by hand. Anyway, tenon length is typically 3X it's thickness, so if the tenons are 1/4" thick you would make the mortise 3/4" deep, minimum. There's no harm in going deeper, but not much benefit either for cabinet doors.

If your rails are 3-3/4" wide I would make the tenons about 2-3/4" wide. That leaves you room for 1/2" deep panel groves and also 1/2" at the end of the stile. If you use plywood for the panels I would do as Rod suggested and glue them into frames with simple stub tenons.

John

[Aaron Rosenthal]

Thank you Rod & John. Plywood is certainly easier and faster, and after this length of time, I just want to get finished!
Tenon depth will be 1 1/2". The joy of having a dedicated mortise machine!

[Bruce Wrenn]

The joy of having a dedicated mortise machine!

I too have a mortiser, but after looking at Phil Thien's mortising jig for the router, I may get rid of my mortiser.