do I really need wing spar spacers?

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RV9inIowa
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do I really need wing spar spacers?

Post by RV9inIowa »

Hi everyone - My kit arrived just before Christmas and I've finished the firewall and center section:

Image
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.... but I have a question :?

The manual tells me to make some fake wood wing spar spacers (1 7/16 thick, exactly!) and then test fit the center section bulkheads around them. Not sure what I'm testing. They will fit, I'm sure. Do I need these spacers later on in fuselage assembly? I can't find them referenced in the manual. I've found some posts where people say you don't need them. What does this group think?

I know some people have made the spacers up out of aluminum - that sounds like the way to go if I have to have them. Anybody have a spare set they'd be willing to part with?

Back to work tomorrow, :(
Dave G.
Building N149DG RV-9A Finish Kit, O-320-E2A, Dual AFS-3500
Flying the restored N3689Q, the lowest time airworthy Beech Super III.

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cjensen
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Post by cjensen »

I made mine out of wood, don't know if I really needed them or not. I know some people have built the center section without them with no problem. Seems like it may be a carry over from the 6...
Chad Jensen
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TomC
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Post by TomC »

Dave,

I agree with Chad :roll: Don't waste alot of time making spacers that are works of art. The prepunched holes in both the spars and the skins only allow the spars to be installed in one location anyway. These spacers must be from requirements for older, non-prepunched kits such as 3,4&6's. Even with the spacers, your wings will still probably be a tight fit, but what's the problem with that.

Good Luck,

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captain_john
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Post by captain_john »

Well, I really like my fancy al-yu-minee-yum ones!

They don't expand or contract and are perfectly dimensioned every day!

Yah, they are overkill, but that's what I am all about.

:) CJ
RV-7
Garmin G3X with VP-X & a TMX-IO-360 with G3i
It's all over but the flying! 800+ hours in only 3 years!

chappyd
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Post by chappyd »

The use of spacers makes sure that when you match drill and rivet, everything is in perfect alignment so that your wing spars fit the slot perfect. I made up blocks of steel with holes for the bolts, and ground them to 1.438" ( I work in a machine shop)

I wouldn't drill and rivet my fuse together without them in there. You could easily end up with slop, or an extremely tight fit. Even .005 too tight would make it almost impossible to mount the wings. Don't forget , we are talking about the very heart of the strength of your airplane.

If I were to do it again, I would just hve 4 aluminum spacers made up. The steel was overkill and way to heavy to mess around with.

Just my .02
Dave Chapdelaine
N821RV (reserved)
Fuselage
www.davesrv7.com
web site not updated frequently---I'm building :)

Who am I kidding? It's never gonna be updated again, lol. Been so long I forgot how :)

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