Garden Gate - joining a circle to rails

[Buck Williams]

Just wondering if what I'm thinking is sound. I am building a garden gate that swings between an arched opening in an arbor. The gate is made of
1-1/2" thick red cedar. The top of the gate, or door, will be a 35" diameter
circle of 1-1/2" thick by 3-1/2" wide cedar. Picture a nice open circle at the top of the gate. The rails of the gate will join the circle approximately a third of the way up the circle. To give the gate some rigidity, the lower part of the circle, will join a horizontal stile. The portion of the gate below that stile will be a solid 3/4" cedar panel, should also add some firmness to the gate. The question is, how to join the circle to the rails. I can copy the radius of the circle into the rails with a pattern and a router bit so that it fits nicely. The easy way out, with the equipment I have would be to route a groove in both the rails and the circle, (with a slot cutting bit) and fashion a curved floating 1/2" thick tenon, and glue it together. The tenon would end up being 1/2" thick by 3/8" deep. The question is do you think that it would be a strong enough joint to stand up to the weather and the beating over time of opening and closing the gate? I've been unable to copy a picture of the gate that I found on the web, thus the long description, I hope it's intelligible. Thanks

[Jamie Buxton]

The other dimension of the tenon is that the thing is something like 10" long. That's a lot of glue area.

You can also buy a smaller bearing for the slot cutter to get a deeper slot. The typical slot cutter has a 1 7/8" cutting diameter, and a 5/16" arbor. You can put a bearing as small as 1/2" on that, for a cutting depth of 11/16". That'll give you more glue area.