Hi, my name is Renato and I’m super new here. I do woodcarving and decided to build the gate and garage doors for my home, it’s my first time doing anything like that. All solid red cedar. For the top rails I plan on using tru mortise and tenon to attach it to the styles. Is that a good idea? Attached is my drawing for the gate and you can see in blue markings for the mortise and tenon. Any feedback will be greatly appreciate. Cheers!
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Through mortises are fine for that application, and as you show in your drawing, having the mortises and tenons horizontal rather than vertical will help keep water from getting into them if there are any epoxy or glue gaps. Having said that, there may be an advantage to not having them as through M&T's to offer a little more protection from the weather. It may not be that much better, so I think I'd be comfortable making it either way.
Thank you for the note! I still need to do some research on what kind of glue will last outside but I'll try to keep the m&t gap free to prevent any water issues. Thanks again!
+1 for blind mortises. No real added strength with through mortises and exposing the end grain of the rails is a disadvantage in the long run.
Thank you!
If you are using western red cedar, that species is very rot resistant. You can also use Titebond III, which is waterproof and holds up really well. I built a Japanese bench with mortise and tenons out of western red cedar 10 years ago using Titebond III and it is still going strong.
Question. Instead of using glue, why not try pinned mortise and tenons?
Hi, that's what I intended at first and then looked at wedged m&t. I am gravitating towards glue because from what I read it may hold better. And the garage doors are quite bigger than the gate, each door measuring 7x7 ft. I am guessing my way here and hope it will all workout. Thank you!
I just had another look at your design... Have you considered mortising the top & bottom rails instead of the verticals? This may shed water better, especially with blind M&Ts.
Hi, I considered that for the top but rail but assumed the way I planed it would give the long rails more support, I worry about sagging over time. Thanks you!
If you make your joinery nice and tight then using a polyurethane glue is best for water resistance. That having been said, waterproof PVA will stand up to anything less than soaking.
I would use bridle joints for strength and simplicity in this application, especially if your members are large, rather than M&T - with poly glue there will be little or no water penetration. End grain is exposed either way
Hi Rob, I did not consider bridle joints but will now. I think it could work specially for the garage doors since the top rail will have some protection from the weather. I keep thinking a M&T would be more resistant since the tenon is encased by the mortise. I just need to get overt that. Thank you!
I am making a very similar pair of doors and have used a mixture of bridle joints and 2 inch deep M&T.
The problem I had was cutting 6 inch deep mortices accurately was quite difficult, whereas cutting accurate bridle joints of that size is easy.
There really is no advantage in my opinion in choosing M&T over bridle joints or vice-versa. The bridle is open at the top, but much stronger overall. There is less end-grain exposed at the top of the joint, but this is balanced by the joint lines. I would have preferred through M&T but that was for aesthetic reasons only. The mortice only has to be a little wiggly for it to be way weaker than a bridle joint. I will use Gorilla Glue for the sticking as it is totally waterproof.
I did consider using an auger bit to create through mortices, but could not fit the timber under my small drill press. I tried to make an accurate mount for my hand drill, but too much play in the chuck made this pointless.
Faced with buying a new drill press (not a terrible idea...) I opted for the easier choice.
If you're sold on m&t I suggest pinned loose tenons. No openings exposed to the weather and you could draw-bore one end for tightness. Just a thought. Mikaol
I assume your rails and stiles are fairly wide, given the size of your doors. Tho red cedar doesn't expand and contract as much as more dense hardwoods, you still should pay attention to cross grain construction challenges. I recommend your original plan of M&T's, but not thru mortises. I would make them about 3"x3", and use waterproof glue (my favorite would be Titebond III.) I've seen a lot of old doors with thru M&T's and broken joints, probably from cross grain conflicts. The Titebond III has enough flexibility to not be easily broken in moderate size joints. Pegging the joints is fine if you want to. Not using glue will seriously decrease your doors' longevity, esp. in soft wood like cedar. Any movement will compress areas of the joint, adding to the range of movement. The blind M&Ts will be much more weather resistant than a bridle joint.
Woodworking is full of compromises, for example the size of the tenons: the bigger, the more glue area, but the more cross grain strain. The thickness of the tenons: make them too thick, and the walls of the mortise suffer. Make your choices and enjoy the doors and gate!
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