I have marked up most of the pieces for sawing, though:
- u-shaped rails - two lengths at 21 ", four at 13 "
- threaded rods - one length at 24 ", one at 12 ", one at 18 "
- MDF - four rectangles of 8.5 " x 11 ", one at 24 " x 22 "
The last rectangle is to be the base, with a 24 " front. This is the length of the x-screw thread. The distance front to back allows for the 18 " y-screw thread, with some added clearance in front of and the length of the rear upright added on. This may turn out to be too big, but I can always cut it down, whereas I can't grow it!
I warn you now, this is going to be a nice little mix of metric and imperial - just like the UK!