This roll bar is costing me a lot of hours, but it is finally starting to look right.
I spent a couple more hours working at the straps radius, to get them right.
Fuselage 611 [800x]

Fuselage 613 [800x]

Then I marked the rivet locations, and began drilling the straps to the roll bar sections.
Fuselage 614 [800x]

Fast forward a few hours…
Fuselage 615 [800x]

Then I cut some wood blocks to 1⅜”. These will work as spacers between the sections, to ensure the roll bar becomes 1½” thick. I cut 3 more blocks than shown in this picture.
Fuselage 616 [800x]

The forward sections clamped down.
Fuselage 617 [800x]

…the centre lined up!
Fuselage 618 [800x]

Then I removed every second cleco, and marked and drilled the forward section rivet locations.
Fuselage 619 [800x]

I did the same thing to the outer strap rivets. After all holes were drilled, I took everything apart. Then I deburred the holes and adjusted the flanges of the forward sections, to reduce gap. After clecoing everything together and rechecking the dimensions, I began enlarging the holes to the final “.
Fuselage 620 [800x]