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Old 05-25-2023, 05:11 PM
SolarYellow SolarYellow is offline
Join Date: Feb 2023
Posts: 229

Been meaning to do this for awhile. This thread finally prompted me to do it.

Pulled the scans of the laser cut fins and the old paper template from the JimZ archives into AutoCad and marked the lines, eyeballing to the center of the pixelated messes. Then put dimensions on them as would be needed to enter into OpenRocket on the free form fin option. Did all four of the fins on the lasered sheet and took an average; just did the one on the old paper template.

The result was not quite as great as I expected. Almost more interesting that a difference that subtle could actually be seen visually.

It does seem to indicate to me that a lot of the upscales and downscales available commercially in the marketplace are not very accurate in their reproduction of the original, either old or new, as there are really significant visual differences between the Estes fins and some of the other kits out there.

Anyway, here are the results, both visual and numeric. Old fin outline is green, new is orange. (ETA: swapped out the graphic with a new one IDing the outlines and aligned them at the TE root apex rather than the LE root apex, because that's how they're installed on the rocket.)

OCD can be a serious PITA, but I do like knowing answers.
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