Door/gate construction questions

[Mike Henderson]

My wife wants me to build a garden gate. She does give me conceptual drawings which I have to figure out how to build - see the attached picture. The gate will be about 70" high and about 36" wide and will have vertical slats with a narrow space between the slats, maybe 1/4" or 3/8".

Question 1: I plan to mortise the rails into the stiles. The stiles will be wider than shown in the picture, maybe 4.5 inches. I'm concerned about wood movement, especially since the gate will be outside. I'm thinking about making a double tenon on both rails. Do you think that will work okay for wood movement?

Question 2: Do you think this joinery will be strong enough that the gate won't sag?

Question 3: What glue would you use? Epoxy?

Question 4: Right now, I'm planning on using white oak. What other wood would you recommend that's reasonably priced and will stand up outside? Mahogany is too expensive.

Any other comments you'd like to give a novice gate builder will be appreciated.

Mike

[Jamie Buxton]

I've built some outside furniture, and seen some of it die.

One thing I've learned is important is to design joints and pentrations into the wood so that water does not get inside and stay there. You want water to hit the gate and bounce or drip off. In SoCal, water on the surface will dry off in a couple of days. For instace, if you mortise the bottom ends of the slats into the bottom rail, water is likely to pool in the bottoms of the mortises, and that's bad. One trick I've started doing with M&T joints is to use real glue -- epoxy or urea-formaldehyde -- on the tenon faces, and caulk on the shoulders. The hope is that the flexible caulk stays stuck to the wood on both sides of the shoulder, and keeps it sealed against the weather. I don't yet have long-term testing on this trick.

Another thing I've learned is to avoid letting end-grain look up at the rain. End-grain is the face designed to accept water. Face-grain resists wetting much better. For instance, you can have your top rail cover the tops of the stiles.

White Oak makes a good gate, although it makes the gate feel oddly heavy. You might consider Western Red Cedar. It is weather-resistant like White Oak, but lighter. It is somewhat less expensive. Steel fasteners will stain Oak or Cedar. Use brass or bronze for a cedar-like color, or stainless-steel for a contrasting color.

[Alan Turner]

Mike,
I agree with Jamie's comments. You might consider Spanish cedar. It is light weight and both bug and decay resistant.

Epoxy is the way to go for the glue-up. If the slats are mortised into the bottom rail, then consider adding weep holes at the bottom of the mortises so that if water does penetrate, it will be able to drain out.

[Mike Henderson]

Thanks for the advice. Jamie - thanks for the tip about end grain. I'll watch out for that in the design and make sure it's covered or sealed well. Alan - that's a good idea to drill weep holes in the bottom of the mortises. What I plan to do is put excessive glue in the mortises so that I am assured that the joint is completely filled - but the weep hole is good insurance.

And I'll check into the two types of cedar you recommended.

I'll post a picture when I complete it. Thanks again for your advice.

Mike

[Greg Cole]

110% agree on the end grain treatment. Preferable to hide-cover it, but at least give it a couple healthy doses of a sealer. Epoxy is the best choice for adhesive, IMO.
Spanish Cedar is not cheap either. I looked into making exterior shutters for home after a complete exterior remodel... until I found it was $10 a BF.
I refuse to spend a couple hunders bucks on nice premade ones and the plastic ones from the BORG are just not acceptable either. I haven't deicded which species I am going to go with to make the shutters, but just might fall back on cheaper red cedar and try to "cherry" pick some clearer material....

Greg

[Greg Cole]

Hey Mike,
Was pondering while sitting at my desk thru lunch.... Cypress is another great species for exterior usage. Honestly, I never priced it for my shutters... gives me something else to do during my lunch I guess.

$0.02 donation...
Greg

[Mark Vaughn]

So would you recommend you using epoxy instead of wood glue for all of the joints or just where rain is likely to pool?

[Bob Smalser]

An automatic 16-footer on copper-capped 8X8 posts, now 8 years old with no sag. Western Red Cedar throughout, dovetailed corners and PL Premium Construction Adhesive. Hardware is hot-dipped galvanized and hinges through-bolted to frame. Screws don't hold sufficiently in cedar in high-stress applications.





These dovetails cut with a saber saw are easier to do than M/T for this type of frame construction and are less likely to fail because of more contact surface to resist racking stress. Surfaces are sealed using glue and Olympic pigmented stain. Expect the joints to move some seasonally....it won't matter providing you keep them sealed.

If you use M/T for a frame-panel gate leaf, drawbore them so they'll remain stable should the glue fail. Looking at the proportions and proposed size of your top rail, I'd probably use either three drawbored tenons or even a long T&G pinned in three places. Using stable WRC, wood movement won't be a problem, although I'd try to use VG stock for wide rails.



Posts treated with copper, tarred, set in sloping concrete and the concrete tarred. Decorative caps cover carriage bolt ends.



And I'd stick with WRC for its light weight, relatively inexpensive cost in California and rot resistance....in frame and panel construction it can be lovely:

[Wiley Horne]

Mike,

That is going to be a beautiful gate!

Water penetration has been well covered.

I think the bigger problem is going to be sag. Gravity never sleeps, and on a gate that size--6 feet high and 3 feet wide--all that cantilevered weight puts huge strain on the corner joints, and all the weight has to get to ground through the post on the hinge side. In my experience, the slat joinery won't do much to prevent sag--you're counting on the 4 corner joints to react all the weight.

Here's how I think you can help yourself:

1. Don't use oak. As others have said, use a lighter (weightwise) wood.

2. Do you need the full 36" width? Can you go 30" for example? Or 33"? Every additional inch of width makes it more difficult .

3. I would suggest making that bottom rail wider. It will be taking the lion's share of the load. It'll be foreshortened in perspective, so you can afford to make it 15-18" wide. In general, make those top and bottom rails as wide as you can stand aesthetically. You could also pierce them perhaps to lighten the look, and still have the same joint strength.

2 cents.

Wiley

4.

[Chris Padilla]

http://www.sawmillcreek.org/showthread.php?t=81446

Mike, I'm buidling a gate out of WRC right now. This weekend will be the big glue-up! I'll have more pictures to add to the thread. It is a monster at about 4' wide by 7' tall. I may need to add a gate wheel to it but time will tell.

Cedar has been interesting to work with. It is soft...very soft...it dings up easily if you look at it wrong! Milling it has been fun...the whole shop smells so nice! It is light, much lighter that oak although I think both might stand the test of time...just like redwood probably would.

I'm using epoxy to glue it up and I cut no mortises that could possibly fill up with water. Only the groove holding the center panel slats and upper lattice might hold a bit of water. I plan to seal the end-grain of those slats in hopes of minimizing absorption. I'm just going to brush on some epoxy to the end-grain and hope it suffices.

[Von Bickley]

My vote would be for Cypress......