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prkaye

Well Known Member
i just had a minor freak-out.
I diligently followed vans plans and lined-up the aft ends of my longerons (these are already bent and the aft canopy decks are already clecoed on)with the aft edge of the last tailcone bulkhead. Then I notched and prepared the aft ends of my main longerons . After a serious amount of puzzling and struggling to get the center and aft fuses aligned so that the side skins will fit, I immediately saw the longerons were way out of position...the forward end of the longeron stick out about 7.5 inches beyond the front edge of teh forward side skin, the downward bend is about the same destance forward of the downward bend in the upper edge of the side skin, and the canopy decks are correspondingly too far forward. It LOOKS to me like what i need to do is push the longerons back about 7.5 inches, and then chop this amount of the back of them. Before I do this though, I wanted to find out if you 7/9 builders experienced this as well... am i correct in my assumption about what's going on here?
Thanks,
Phil
 
Sounds to me like you did not trim the stock that Vans sends you to length before measuring where to put the bends. The stock they send you is too long and must be cut to length.

The downward bend on mine ended up exactly at the downward bend of the side skins.

Before hacking or rebending, figure out what went wrong. But if this is true, I think you will be correct in cutting the extra off the back. But, the notch for the vertical bars may not fall in this distance and if so, you would end up with two sets of notches.
 
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Yes, i didn't cut them to length yet.
Am i correct that the forward edge of the aft canopy deck (28 1/4" back from front edge of longeron) is supposed to line up exactly with the spot on the side skin where the top edge takes a bend downward? Is the front of the longeron supposed to line up exactly with the forward edge of the side skin?
 
prkaye said:
Yes, i didn't cut them to length yet.
Am i correct that the forward edge of the aft canopy deck (28 1/4" back from front edge of longeron) is supposed to line up exactly with the spot on the side skin where the top edge takes a bend downward? Is the front of the longeron supposed to line up exactly with the forward edge of the side skin?
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The downward bend must line up with the downward cut of the side skin.
 
Phil,

You mean like this?

I was so proud of that picture and then realized what I had captured. Ugggg...

Brian was correct, follow his advice.
 
The downward bend must line up with the downward cut of the side skin.
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Right, so that would leave the front of the longerons about 3/4" aft of the front edge of the side skins, which makes sense i guess to leave room for the firewall flanges.

Thansk! Everything looks better now. Will take a break now and hack off the back ends of those longerons and re-notch them later this week.
 
prkaye said:
Right, so that would leave the front of the longerons about 3/4" aft of the front edge of the side skins, which makes sense i guess to leave room for the firewall flanges.

Thansk! Everything looks better now. Will take a break now and hack off the back ends of those longerons and re-notch them later this week.
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Yes, I don't have my manual handy right now but there is a measurment later in the manual that you must have between the end of the front of the longerons and the firewall. Most of us have had to trim a little off to get that distance.
 
Yes - it states such in the instructions. And yes, Phil - the aft canopy deck leading edge is at the sharp downward bend 28 1/4" from the unbent longeron forward edge.


Bob Collins said:
Correct me if I'm wrong. It's been awhile. But don't the instructions call for the longerons to be cut to length before any bending? (and twisting?
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