Rotorway Forums

Rotorheads Nov 2021










P.S. posted as image and PDF to see which is more convenient.

After following this writeup, the things i noticed and want to add is my factory skin measured about 1 inch longer than what he listed as the 130-1/2" this isnt the biggest deal but with my CHOPCO sliders which were already drilled to the skin now only 2 of the 4 existing rivets on each four slider location lays over the skin... oops, wish i saw that before. not the biggest deal as i can drill 2 more additional and its still adequately supported, if it were the original sliders maybe not so. 

I also want to EMPHASIZE how much this skin wants to "pucker" out between the bulkheads. its the lower 3 closeout panels that hold everything together straight and true in the end, he mentions using safety wire to hold it in the interim with some additional skin. you cant get the panels to lay flat to drill them to the stringers/skin with the safety wire in the way. you could fudge it but i found it easier to drill all holes in the 3 panels first off the boom, then with the skin off the boom i could lay the panels on the frame on the jig, drill the stringer in an unstressed/unpuckered state with the panels laid out at their dimensions from the datum and centered. ( i made sure to put a curve in them before so they didnt end up just being flat. ) then once all panel holes drilled into stringer, lay the skin back on the frame one side at a time and transfer the closeout panel holes now in the stringers to the skin. doing it one side at a time allowed easier access from the inside drilling out as well as minimized the "puckering" of the stringers.

My final note i have to add is regarding stringers, i found mine were subpar manufactured and i could squeeze the tailboom between the #2 and #3 bulkhead and get alot of flex where i dont think flex should exist. i used 3/4"x3/4" 12' 2024-T3 Aluminum Angle extrusion of .063" thickness as well as tied the stringers back to the bulkheads to prevent sagging of the stingers i noted with my original build. i then opted to use solid aluminum AD rivets and doubled the rivet count/halved the rivet spacing. these choices were mine. i dont recommend them unless you want a fun sheet metal project. 

as with all sheetmetal, debur, etch, alodine, take your time.

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Well,  That's very impressive.  A job for a single person or a person with a very understanding spouse!!!

all rivets were able to be single handedly bucked which is always my preference. not sure the wife would hold a tungsten well but she damn sure is very understanding!