So I went and re-read Mustangs Mega Mosquito build thread on TRF.
The finished product looks great! Very clean work.
I found the picture of the outside fin edges pretty interesting.
(Photo at right by Mushtang)
All three of his fins had the center core piece slightly recessed when looking from the outside rounded edge.
When I glued mine up I purposely stepped the core middle piece to fit the curve of the body tube.
That would push the middle layer out making the rounded outside edges even.
I wonder if Estes purposely cut if the interior (tabbed) fin a little shorter?
If the builder glues all three of the outside rounded outside edges flush instead on concentrating so much on the root edge) would the three glued root edges end up "stepped" to automatically fit the body tube curve?
If so, this should have been addressed in the instructions.
Just reviewing this post (I'm thinking of a scratch build with similar laminated fins) and I decided to crunch the numbers. I conclude that in order to "step" the layers to conform to the body tube curvature, the root-to-tip distance for the outer layers should be longer than for the middle layer by... just under half a mil. Or in other words, about half the thickness of the plastic used in the parachute.
ReplyDeleteI really doubt Estes is laser cutting to half mil precision. And if they are, I'm sure I'm not sanding and gluing to half mil precision.