Gotta love the discovery of old, unknown mistakes! I fit and drilled the 721 aft canopy deck to the longerons about a year ago. Since then I've built the fuse and have finally gotten to the point of starting the finish kit. I had decided to leave them unriveted until I was just about ready to start fitting the canopy frame, and today I grabbed the aft canopy deck pieces from the pile of painted and ready parts, and got ready to finally make them a permanent part of the fuselage! Now that the roll bar and other parts were riveted in place, I looked twice at the fit of the aft deck and realized I must have measured incorrectly way back when! The aft end of the 721 is about 1/4" from snugging up against the canopy roll bar attach bracket. Out of curiosity, I looked at the other side - same thing. I've looked at other build logs, and as best as I can tell, the deck is supposed to butt up against the roll bar. I've had these parts on and off about 100 times, but for whatever reason, this fit just never clicked with me.
There's not much I can do about it at this point - longerons are drilled, riveted to skins, firewall, etc. I had a tougher time than I thought I should getting the forward canopy decks to fit in between the aft deck and the outer sub panel, but chalked that up to just being a tight fit. I've already fit the forward top skin on, and with the canopy decks in place, it seemed to fit okay. Tight, but no tighter than some other skins.
I'm guessing this means that my longeron bends are probably 1/4" off from what they should be. I'm just hoping that this difference won't bite me when working on the canopy frame. I think in the end this is probably not a big deal and I can deal with the trickle down effect of the error. I'm just super irritated that I managed to make the mistake. I remember measuring multiple times because I was paranoid about drilling the longerons, but obviously either looked at the wrong number or had it wrong in my head.
Here's to hoping this is the last ancient mistake I find.
There's not much I can do about it at this point - longerons are drilled, riveted to skins, firewall, etc. I had a tougher time than I thought I should getting the forward canopy decks to fit in between the aft deck and the outer sub panel, but chalked that up to just being a tight fit. I've already fit the forward top skin on, and with the canopy decks in place, it seemed to fit okay. Tight, but no tighter than some other skins.
I'm guessing this means that my longeron bends are probably 1/4" off from what they should be. I'm just hoping that this difference won't bite me when working on the canopy frame. I think in the end this is probably not a big deal and I can deal with the trickle down effect of the error. I'm just super irritated that I managed to make the mistake. I remember measuring multiple times because I was paranoid about drilling the longerons, but obviously either looked at the wrong number or had it wrong in my head.
Here's to hoping this is the last ancient mistake I find.
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