I have not found a single discussion on this subject so mine must be a unique situation. I just finished making the first trim of the canopy (7A slider) removing the mold flanges. I set the frame upside down into the plexi looking for the "best fit" position according to instructions, so I can drill the latch hole. There is no best fit ony "less lousy" fit positions.
Here's what I find; the front and rear bows are not a determining factor, as the spacing doesn't change much in the range where a fit is possible.
Therefore, the only factor seems to be the shape of the top center support relative to the plexi. About 2/3 of the way back from the front bow where the center support reverses curvature and has a slight "sag" (concave upward), the plexi has no significant sag to it. The side view drawings in the plans all show this curve, so I don't think my frame is badly off. The farther aft I place the frame, the gap (between frame and plexi) in the sag gets less, but never less than 1/4" and at that point the forward part has high centered on the plexi (rocks back and forth) so no joy here. If I push it toward the forward limit, the front part aligns pretty well but the spacing in the sag part increases to almost 3/8". Anybody delt with this situation before?
Here's what I find; the front and rear bows are not a determining factor, as the spacing doesn't change much in the range where a fit is possible.
Therefore, the only factor seems to be the shape of the top center support relative to the plexi. About 2/3 of the way back from the front bow where the center support reverses curvature and has a slight "sag" (concave upward), the plexi has no significant sag to it. The side view drawings in the plans all show this curve, so I don't think my frame is badly off. The farther aft I place the frame, the gap (between frame and plexi) in the sag gets less, but never less than 1/4" and at that point the forward part has high centered on the plexi (rocks back and forth) so no joy here. If I push it toward the forward limit, the front part aligns pretty well but the spacing in the sag part increases to almost 3/8". Anybody delt with this situation before?