Mortise and Tenon- Advice Needed

[Liam Murphy]

I'm replacing an exterior door that leads to a deck; more specifically, a set of French doors. There will be no muntins or mullions. I'm replacing the existing doors, and they have to match another pair on the other side of the deck.The rails and stiles will be 7/4, with a 1/2" groove for the glass. The wood is eucalyptus grandis. I'll be using hand tools exclusively;thus, I posted this here.

Initially, I planned to make the tenons/mortises 5/8" thick-which is about 1/3 of the thickness of the stock. Then, I realized I could avoid stopped grooves, if I made the tenons 1/2" thick. After some searching I found a few references online to people building exterior doors with 1/2" thick mortises and tenons. However, this seems a bit thin to me. What do you think? How thick would you make the tenons/mortises?

[Steven Green]

I'd make them 5/8 just because the numbers add up. But, I don't think there would be anything wrong with 1/2 strength wise. It would be to your advantage time and work wise to go with the smaller measurement that's for sure.

[Liam Murphy]

Thanks Steven. Anyone out there think 1/2" is too thin?

[Tony Shea]

I guess I don't completely understand why this would prevent the stopped grooves as opposed to have 5/8" wide mortises. Wouldn't this just require you to widen the grove 1/16" on each side where the mortises would be? I might be undestanding this incorrectly though. I would try all I could to get the 5/8" mortise. Doors get beat up pretty bad and I would think that they would benifit from the extra 1/8" in size. But like was said before, if it prevents a bunch of work then maybe the trade off is worth while. It will have to be a personal decision on your part I would think.