RV-12 Stub spar/receptacle

I have the fuselage completed to the point where the stub spar/receptacle must be fitted.

I also have the wing underway and have completed the stub spar sub assemblies. It has been my long term habit to remove machining marks as I go along, and I did so with the stubs. I then did a trial fit to the receptacles and they slid right in.

The fit in the semicircular area is good but if the stub is pulled back even 1/8" from the receptacle vertical play appears between the stub and its receptacle.

Question - When the wing is mated to the fuselage does the stub spar fit right up against the back of the receptacle? Is any vertical play acceptable if the mating does not fit tightly against the receptacle. Any thoughts appreciated.

The forward and aft stub spars should be tight with no movement after the two spar pinds are installed. If you do have movement after both wings are installed and the pins are installed then you can add shim material to the front / outer surface of the stub spars until there is no play in the wing. You can check this by grabbing the hand hold on the end of the wing and moving it up and down and fore and aft. There should be no "clunking" .

Typically, after painting and you add the wing root / fusealage seal there is enough pressure from the seal to keep the wing from moving, but IMHO you should shim the wing if there is movement.

Thanks for the response. Since I do not have the last three kits at this time, I was reluctant to continue with wing construction, particularly skins without knowing more.

You can certainly build the wings, just clean up the spar stubs after you are done so they fit correctly. The instructions say to fit the spar stubs into the reciueveing sockets before assemply, but IMHO that should be done when you are fitting the wings.