Gate braces. Which way should they be cut?

world of the Sims I guess you could get away with too .....

picture the hinges would be on the left.

The idea of the brace is to stop the horizontal rails from sagging. So the hinge-side upright, the top rail and the brace need to form a rigid triangle. Having the ends of the brace cut like an arrow into each corner is ok. A better engineering solution is to cut them so that the bottom end is attched *only* to the upright (and doesn't bear on the bottom rail) and the top end supports the top rail from below - as near to the remote upright as possible, but not attached to it. However, this looks a bit asymmetrical because the whole of the brace it then above the diagonal.

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Mike Barnard saying something like:

It's quite consistent - the brace goes from the bottom hinge to the diagonal upwards as in it counters the forces that make the gate slouch.

I would agree with that. The diagonal really wants to form a gallows bracket, and that is what carries the load of the rest of the gate.

There is one allowable exception in my book though, and that is when the gate is a lightweight one made with uprights, and the ledge and braces are just planted on the face and screwed or nailed to all the uprights. Rather like this one:

My garden gate is built "the wrong way round" and as a result I have had to add a tension wire to the back of it to stop it sagging. The diagonal timber is doing absolutely nothing.

It was like that when I moved in, and I'm not going to change it as it has faded along with the fence!

Andy

One point you might keep in mind is the expansion of the wood. I made a small gate with the diagonal brace very tight in the summer, but there was still a bit of sag in the winter: nothing serious, but another time I would make make the brace even tighter - even lifting the latch corner a little to allow for it.

If the brace is not in compression, the joints will tend to pull apart, especially when the timber is old and cracked. So the joints have to be well nailed or preferably bolted. I didn't like the look of just a single brace so I have two on my small gate. It seems to be very strong. I can climb on both these gates despite them being made entirely of 40x40mm and 40x20mm timber which I had left over from another job. I drilled holes through the frame and down into the braces and used 4 inch nails on all the braces, and glued them as well.

Gates are basically triangles (in terms of forces) with a rectangular filler panel to keep stuff behind them. For a big gate, hang a diagonal down from the hingepost to the far corner. For extra strength, raise this diagonal above the gate itself on an extended upright (a fairly common traditional design). For a narrow gate, it doesn't much matter.

Hi again everyone.

Thanks for all of your replies, it's great when the obvious is pointed out, isn't it. I had triangulation in my head but I didn't think of that 'Gallows' effect. Anyway, I have it braced now and all ready to paint. I'm sure it will last for a long time.

Mike.

Are you going to post a picture of the finished article?

Heh, if you're *really* interested. No binaries on here so...

Mike.

Nice job. How did you join the ledges to the uprights?

The gate looks good. I'm not quite sure what keeps the posts upright, though.

Thanks. A bit of a bodge I feel, but it'll do for a while. The Ledges? I assume you mean the cross members, the lefty righty bits? I don't know all these posh 'correct' names! :)

Mortice and tennon joints. 20mm wide, full height and 30 mm deep into the uprights.

I used those drill and hammer/screw in window frame screws for the 'posts' I used for the gate in our side passage. Been there for years and no sign of coming out yet - even though I broke the head off one of the screws with my impact driver...

Problem is though - in the case under discussion - the posts are not directly connected to anything solid, the nearest brickwork being at the other end of short lengths of picket fencing - which will provide very little rigidity in the plane of the (closed) gate.

Wrong. I've bolted the posts at the base into the brickwork that surrounds the steps. When I get around to hanging it I'll find out.