I started out with the best intentions to get the side hinge lines accurate and level with fuselage longerons to within 1/16". HF rotating laser level. Months of working on it, on and off.
I did not want to get into major surgery on it, and I wanted the upper cowl cheek bows left/right to be close to the same distance to longerons at the firewall and also symmetrical inlets. Why I ended up with nearly 1/2" difference between left and right side hinge lines to floor, I do not know. (Wings off, so final numbers may be different.)
When I got to the point of nearly giving up, I relaxed my precision goals.
I have yet to discover why the cowlings are made with a 1/2" or bigger gap to the spinner on the right side compared to the left side. The engine offset really does not explain it. My cowling is the greenish and honeycomb generation.
Forming the cowl cheek extensions out of alum took several weeks (taking a lot of breaks). Again I think one of them ended up 1/8 or 1/4" off the ideal parallel line to the longerons. Why the drawing notes that they should end 7 1/2" below longerons, I don't know. I calculated 6 3/8" from the drawings, I think.
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Last edited by FinnFlyer : 08-20-2019 at 07:57 PM.
Reason: Added more text.