Thanks for the kind words guys, I get a bit random every now and then so if you see something I'm doing is a bit off please stick the boot in.
I bought 1 1/4" DOM tube for making the frame.
Didn't go ChromeMoly, figure if I get the design & welds reasonable the DOM will stand up ok.
The main hoops are ellipses to follow the body shell.
After ringing a few specialist tube benders I worked out the answer to " Can you bend some ellipses for my rollcage/frame?" is Click.... Beep.......beep. Sooks.
A guy who builds boats in a little industrial area has a tubing roller & a dirty shed.
He now has a clean shed & I got to use his roller for a few hours;
I rolled the whole tube length to the biggest radius then worked my way into the middle in stages tightening up the radius in stages.
The first one (in pic) took about 3/4 of an hour with lots of in an out of roller and testing in the profile.
I wrote down the measurements for each segment & the others the same took about 10 minutes each.
The halves will joint at the widest point and their joins wil intersect the belly rail joins.
Pic of the rear ellipse halves trimmed and laid in the shell profile at that point;
The rear engine mount, swingarm, rear suspension, chute pull mount stays & chute tubes all tie into this hoop.
The main ones follow the top and bottom better, old mates roller couldn't come in tight enough to get the tighter radius.
Made a jig up for my lathe and chucked a 1 1/4" endmill to notch my tube;
Dint be picking on my favorite G-clamp either.