Canopy side bars (square tubes)
Luckily my canopy frame side square tubes follow the longeron shape very well, but I spent weeks trying to get the front round tube hoop to match the roll bar shape. After trying: bend by hand
, bend using ratchet straps
, bend using big C-clamp and wood blocks clamped to a workbench
, hydraulic pipe bender
, I finally built a good hydraulic tool. Used a remote hand pump/reservoir and a small porta-power hydraulic cylinder. Built a rather elaborate T shaped frame from aluminum channel and bolted a block at one end for the porta-power. Made some wood bending shoes for the end of the porta-power and the T cross.
But using some tips from another builder, I traced the shape of the roll bar onto the workbench, then I had a good reference for the shape of the front hoop.
My advice would be:
1. If you're happy with the shape of the front and rear hoops, as another poster advised, lock these shapes in place with a fixture (2x4 or whatever).
2. Transfer the shape of the longerons to a workbench.
3. Mount the canopy frame on the workbench so you can use a hydraulic press of some sort to bend the square tube. These are pretty strong and take a lot of force to bend them.