beautiful stuff shutterfinger!
i also have a 3A, but the shutter is kind of wonky
so i use a lens cap and paper negatives
not as high tech as yours, but its OK for now ...

you are probably right, maybe i got lucky !
( with the film plane ) ... i did throw salt over my shoulder
and find a 4 leaf clover before i did the taping .. if i would only be so lucky
with my power ball jackpot picks

thanks for the link!
john