There was a Trapeze Mark I, but it was a rush job and I have no photographs. So, Trapeze Mark II. Trapeze Mark II is a static trapeze made basically from offcuts we had in the shop, partly so I don't have to wait for stuff to arrive from the U.S., and partly so my boss can see that I can make a proper trapeze before blowing budget on 4-lay 1" cotton acro rope from Barry's.

Step one.

Collect 2 thimbles, appropriately sized for your rope, and a piece of pipe[0]. Opinion as to the width of your pipe (or length of your pipe, if you prefer, but it will become the "width" of your trapeze) will vary. In fact, if you ask 2 performers how long it should be, you'll get 3 answers. As an example of this, I asked our 21 year old straps artist (who also, of course, has done trapeze) how wide it should be, and he said "The width of your shoulders plus a hand and a half each side". I asked our head acrobatic coach how wide, and he said "The width of your arse plus a hand and a half each side. You'll need to sit on it at some point". I do not think it occurs to 21 year old male strap artists that their arse may some day be wider than their shoulders. Anyway. I went with the width of my arse plus a hand and a half each side. Which worked out to be about 62 cm, because I have ... wide hands. I rounded up to 65, because that was the second answer I got from the coach. That measurement is internal, rope to rope, so add the width of both thimbles to get the total length. One thing to note here - opinion varies on pipe vs solid bar. You should probably use solid bar, but you should also not listen to trapeze construction advice from strangers on the internet.

Step two.

This may never have occurred to you if you've never built a trapeze, but a piece of pipe has no inherent "bottom". If you're lucky, there will be a seam that runs straight along one edge, in which case this step is easy. Otherwise, you have to somehow ensure that the thimbles are aligned with each other when you weld them. Methods of doing this, of course, range from the long, tedious and accurate through to the quick and dirty. Because I am a Highly Trained Professional (tm), I went with the quick and dirty. You should probably, etc. Anyway. If I were doing it the long accurate way, I would temporarily rig the thimbles from some cable, with the bar in place. Then weight the bar, so it pulls both thimbles down evenly. Basically, you have just replicated the final hang of the trapeze. Mark each end of the pipe with a paint pen so the mark continues on to the thimble. I do this three times per end, but you could get away with one. Yes, I'm inconsistent about the things I do "properly". It's my trapeze.

Anyway. The quick and dirty way looks like this:
Basic jig for truing trapeze thimbles
Ah, threaded rod, is there anything you can't do?
We care not for such niceties as level or square here. The only important thing is that the thimbles sit identically - that the base of one thimble lines up with the other on the pipe. This method gives me less than 2 mm variance in about 60 seconds. I'll take that. For a show rig, I'd do it properly, but I can live with 2mm here - the rope will take that up.
You can't see the paint pen marks here, but there are three of them.

Step three.

That was the hard bit, I promise. Next, jig up the thimbles and pipe. Well, one thimble at a time, that's why we marked them both. Here, we care very much about level and true and square and all that other stuff. The thimble really needs to be square to the pipe vertically and horizontally. Any shear will stress the welds a lot, and you don't want that.
That's squarer than it looks, honest.
I can't believe they pay me to do this. Well, actually, this was on my own time one morning. But the principle remains.

Step four.

Bad photography makes bad welding look like good welding!
Bad photography makes bad welding look like terrible welding!
Ok. This bit is important. Although the welds are not responsible for holding up the bar (the thimbles do that), they are responsible for holding the thimbles *on* the bar. Otherwise the thimbles don't do that. So if you cannot weld, get an adult to help. I have my welds checked by 2 coded welders after I finish, and this is training gear. They don't let me burn metal for show gear, for very good reason.
Dressed welds are sexier than undressed welds. Go figure. Also, please to note the fabulous reef knot tattoo to prove that this is really me building the trapeze. Or at least holding it.

Step five

Et voila! (That's french, and has nothing to do with string instruments). The main thing to note here is that when I sit it on a flat surface, it sits like it would hang - the thimbles are upright and even. If you weld them closer to one side of the thimbles than the other, or get the alignment wrong, you should notice that here.
Stay tuned for the next fascinating installment, wherein I do what I'm actually *good* at, which is splicing.

[0] Points for getting the film reference.