Draker
Well Known Member
Happy new year everyone. Wish I could share in the happiness, but I just found what's possibly a catastrophic mistake I made on the RV, and wanted to share it. Obviously this is going to involve a long discussion with Van's, but I thought I'd start a discussion here to potentially prepare myself for the extremely bad news I have coming.
Long story short, it looks like I built the whole forward and mid fuselage around incorrectly bent and drilled longerons.
I'm at the point in the build where I'm disassembling the forward fuselage to prep the surfaces, dimple, and countersink them for riveting. While countersinking the longerons, something just didn't look right. The top holes I had drilled for the aft canopy deck were way too far aft. So I clecoed the longeron back to the mid-fuselage, and pulled out the F-721B aft canopy deck pieces. Lo and behold, the holes are indeed way too far back:
It looks like way back when I drilled the canopy deck to the longerons, I had the forward edge of it in the wrong position:
How I made the mistake: The distance between "Beginning of Curve" and "End of Curve" is 30 27/32" which is almost exactly the length of the F-721B canopy deck piece, so I ASSumed that it was to be positioned between these marks.
So at the very least, I'm going to be ordering two more longerons, re-bending them both, and re-drilling them to the skins. As a side note, the holes in the longeron-facing aft fuselage skins are already dimpled so it's not going to be fun to re-drill those. But that's the least of my problems.
Unfortunately, as a result of incorrectly locating the canopy deck pieces, my longerons must have been bent in such a way that they align with the incorrect placement. As proof, when I lay the canopy deck piece against the longeron in the correct position, it does not match up with the curve of the longeron:
This means I have built the entire forward fuselage around incorrectly bent longerons. This may mean that I'm scrapping a fair bit of the front fuselage, too, likely at least the side skins.
To say I'm disappointed is an understatement. Please help me brace for the bad news from Van's. I'll be calling them pretty much as soon as they re-open from the holidays. And future builders, please learn from my carelessness.
Long story short, it looks like I built the whole forward and mid fuselage around incorrectly bent and drilled longerons.
I'm at the point in the build where I'm disassembling the forward fuselage to prep the surfaces, dimple, and countersink them for riveting. While countersinking the longerons, something just didn't look right. The top holes I had drilled for the aft canopy deck were way too far aft. So I clecoed the longeron back to the mid-fuselage, and pulled out the F-721B aft canopy deck pieces. Lo and behold, the holes are indeed way too far back:
It looks like way back when I drilled the canopy deck to the longerons, I had the forward edge of it in the wrong position:
How I made the mistake: The distance between "Beginning of Curve" and "End of Curve" is 30 27/32" which is almost exactly the length of the F-721B canopy deck piece, so I ASSumed that it was to be positioned between these marks.
So at the very least, I'm going to be ordering two more longerons, re-bending them both, and re-drilling them to the skins. As a side note, the holes in the longeron-facing aft fuselage skins are already dimpled so it's not going to be fun to re-drill those. But that's the least of my problems.
Unfortunately, as a result of incorrectly locating the canopy deck pieces, my longerons must have been bent in such a way that they align with the incorrect placement. As proof, when I lay the canopy deck piece against the longeron in the correct position, it does not match up with the curve of the longeron:
This means I have built the entire forward fuselage around incorrectly bent longerons. This may mean that I'm scrapping a fair bit of the front fuselage, too, likely at least the side skins.
To say I'm disappointed is an understatement. Please help me brace for the bad news from Van's. I'll be calling them pretty much as soon as they re-open from the holidays. And future builders, please learn from my carelessness.
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