aft canopy deck too far aft

prkaye · #1 11-04-2007, 03:04 PM

Today I put the shallow curve in my longerons, and drilled the aft canopy decks to the longerons. somehow i forgot to double check the fore/aft position, and the left aft canopy deck has been drilled to the longeron about 1/8" too far aft. is this going to cause a serious problem, or can things be trimmed later to compensate for this? is there anything i can/should do now?

LettersFromFlyoverCountry · #2 11-04-2007, 05:12 PM

I can't remember if you're building a tip up or a slider. My comments involve a tip-up.

first, you'll have a space between the forward side decks and the ones you just installed. I don't think you want to pull the whole side decks back 1/8", but maybe.

You may have to trim 1/8" off the back. You've probably already trimmed it to accomodate the gusset plate that connects with the 705 bulkhead (again, if it's a tip-up). Otherwise you may get some interference with the brackets at the base of the rollbar that go there.

I can't think of anything here that's a deal-killer.

prkaye · #3 11-04-2007, 06:15 PM

thanks Bob. I'm building a slider.
I haven't done any trimming at all yet.
Since my canopy deck is 1/8" inch too far aft, i could cut the 1/8" off the forward end of that longeron, to bring the canopy deck into correct position (relative to the forward end). This will leave my longeron 1/8" too short at the aft end. Would this be a serious problem?
Which is worse, canopy deck 1/8" too far back, or aft end of the longeron too short by 1/8" ?
Are these longerons exactly the right length as-shipped, or do they typically require trimming anyway?

LettersFromFlyoverCountry · #4 11-04-2007, 06:48 PM

Van's is in the best position to answer that question but I would NOT cut the longeron below the suggested original length at all. In the back, you do cut a flange to make the rear bulkhead (712?) fit right. but at this stage of the game, I think you're asking for all sorts of problems to fix one mistake by making another.

prkaye · #5 11-05-2007, 09:19 AM

Any other thouhts here anyone? Can I still use my longeron? I've been worrying for the past 18 hours that I might have to buy and bend a new longeron

I emailed Vans, but usually they take a day or two to reply.

LettersFromFlyoverCountry · #6 11-05-2007, 11:08 AM

Give 'em a call.

Of course, the simplest solution, I guess, would be if you could get canopy deck replacements that aren't pre-drilled. Then you can just put 'em where they're supposed to go and use the existing holes in the longeron.

prkaye · #7 11-05-2007, 11:14 AM

>> would be if you could get canopy deck replacements that aren't pre-drilled. Then you can just put 'em where they're supposed to go and use the existing holes in the longeron.

That's brilliant. I wonder if they would make one for me... i suspect they would have to do it custom (their machines probably pre-punch them automatically).

prkaye · #8 11-05-2007, 11:29 AM

Ah, just got a reply on this from Vans... apparently it's OK to cut the 1/8 off the front of the longeron and shift the whole thing forward. Apparently there is a little overhang at the aft end that gets trimmed anyway, as I had hoped.
Relieved, and ready to build-on!

LettersFromFlyoverCountry · #9 11-05-2007, 11:59 AM

Just keep in mind that if you've bent the longerons, now your bends are off by 1/8" too. Not a real big deal, but you may want to do a little tweaking on the longeron.

prkaye · #10 11-05-2007, 12:06 PM

good point... but the most critical part of the bend is apparently along the canopy deck... I did the tweaking as I was drilling the longeron to the canopy deck... the curves match-up very well (I was pleased how well this went).
Next step is to put that downward bend in the longerons, and then the twist. I'm excpecting this to be easier than the shallow curve.