It's time to sort out the long rails, or stretchers if you prefer.
I'm going to bolt them from the offside of the leg frames, using 200x12mm bolts. The nut will be inside the rail, so I need a straight hole for the bolt and a cavity at the end of it for the nut.
I could try drilling a long straight hole into endgrain, but it's not easy to keep it straight. These rails are too long to do upright on my drill press and I don't have a horizontal borer. So I'm going to rout it all instead.
The first job is to rout a groove 1/2" wide down the broad inside face, 6mm beyond the centre of the thickness. A second router fence stops my router from wandering and a piece of scrap stops my holdfasts from marring the workpiece as well as acting as a stop.
Then I adjust the fences and reduce the cutting depth:
Then glue in a patch to give me a straight, square hole in the end:
Now I need a cavity for the nut and washer, and I also need to to be big enough to get my fingers and a spanner into it. So I made a simple template with a rectangular hole in it. The hole is 17mm bigger than I need, because 17mm is the difference between the diameter of the cutter and the diameter of the bush.
Swap the fences for a guidebush and rout to half the diameter of the 24mm washer beyond the centre of the thickness.
To stop the rail from twisting, I'm going to insert a couple of short dominoes
Finally, to ensure that it tightens up securely. I relieve the very end of the board with the same template. I had to modify it a bit, but I would not had to do that if I'd put the dominoes a tad further apart. Still, it didn't take long.
The cutter was not quite long enough because of the thickness of my template
But a quick whizz with a flush-trim bit sorted that out