RV-8 aft deck not level

[laplander0]

I am getting ready to mount my h stab...I got my fuselage perfect level with a digital level across the cockpit area in both directions an corner to corner...but my aft deck is not level.in fact it takes a 3/32 shim on top of 1 of my 1/8" spacers to get my h stab level..it is a qb kit...is this something to worry abt or just shim it an drill it? Thanks 4 the help n advance
2014 dues paid

[cfiidon]

Have you checked other reference points to determine "level"? It might be prudent to check that the spar carry thru is level. I would think the wing attach points and the horizontal stab should be parallel.

Don

[laplander0]

ok, I will double check the main spar..hopefully it is closer to the aft deck..it does seem like there is a slight twist to the fuselage. .5 of 1 degree difference..I just didn't know if this was acceptable.. i doubt that it is normal

[Vic LaRocca]

We have found those same symptoms here at ORK when the top rear fuselage skin is not in place. If it is not installed yet just try clecoing it on and check for level again.

Vic LaRocca
RV-8 Canopy
Little Rock, AR

[rvbuilder2002]

Actually the drilling and riveting of the aft deck plate is what makes the fuselage torsionally solid.
If the fuselage was slightly twisted when the rear deck plate was fitted and drilled, that is how it will stay without unriveting and match drilling another plate.

[Vic LaRocca]

Mine is a slow build and my partners is a quick build. Aft decks were rivited and top skin was not. Both of us had the same symptoms. When we put the top rear skin on with just clecos the twist went away. They stayed straight after riviting.-Vic

[cjhammes]

OP indicated a QB kit. Wouldn't twist be checked before riveting deck?

[Vic LaRocca]

Please let us know what you find.

-Vic
2014 Dues paid

[laplander0]

I called vans and talked to Kent..He told me not to get to fussy about it..He said a 1/2 of 1 degree was really good. if it was 3 degrees out that would be something to work on. I am just to add a shim because I can but he also said it won't make much difference if I didn't add the shim. alot of turbulant air traveling over the h stab won't know the difference.

[cjhammes]

Thanks for providing the feedback from Vans. Helps to keep it in perspective that again we are not building rocket ships.