I replaced the inner O-ring together with the outer when I assembled the whole thing few months back. Hopefully is just the outer. From the 4 holes I could already see it was in bad shape.. let's see. I wisely bought some extra O-ring as I kind of knew this was going to happen.

The feeler gauge trick did not work for me.
If I used the very thin ones they will break apart when pulling out, if heavier then the all thing will get stuck.
I tried with a thin foil, again no way, the clearance wall to wall is 0.01mm.

So what worked is to cut 4 piecies of a PVC rod and hold them in place with a metal clamp well thighened. I tried to pull the O ring in and out and it was still brand new.

What resin was it used back in 1981 for the glareshield? Poly or epoxy?

What is the gap within the Aileron leading edge and the wing trailing edge on the top of the wing? For -20 deg, neutral, and +20 deg?

Mine is darm close, in the original installation I could see the ailerons leading edges were scratched by it. I’m resckinning the ailerons and flaps, but without skin I can see the ribs very very close to the wing when moving the ailerons up.

Is this a frequent issue, how it is normally solved?

Bend the hinge standoff arms up or down so that the surface is on same plane as bottom of wing.

Could someone share some detailed pictures of the baffling installed on the 540. Specifically how are they attached the shaped around the cylinders. Thanks

can you run the engine without wings and tail feathers installed?
clearly not airworthy

Might be fun to do a fast taxi around the airport though!

I don't think it would be a good idea to have that big gyroscopic flywheel of a prop spinning without the stabilizing effect of the wings. There are several Utube videos of plains running with out the wings for several seconds before they get all wobbly and tip over or stood up on the noses but all of them videos ended with prop strikes. Some of them looked like an attempt had been made to secure the fuselage, didn't seem to help.

Hmm...
On one of Admiral Byrd’s Antarctic expeditions, one of the planes was badly damaged early on, so they removed the wings and used it as a tractor. To pull sleds (the airplane was on skis of course). Seemed to work fine, from the old films I saw. Maybe it makes a difference what kind of landing gear you have. I’ll bet spring steel gear is much more susceptible to the dynamic you describe than A-arm gear, whether oleo or bungee.

We have run the plane w/o wings. I believe they had tail surfaces though. We have a tank made that bolts up to the wing attach fitting. I doubt we ran it up though, most likely only idle.

door mods pics. having curved the frame doing all in one single aluminum piece was very difficult so we opted for stripes. I'm very happy of the results, once painted. we have independednt locks for each door and gas strut for the windows.

door mods pics. having curved the frame doing all in one single aluminum piece was very difficult so we opted for stripes. I'm very happy of the results, once painted. we have independednt locks for each door and gas strut for the windows.

The finished cockpit, the hole on the right will accomodate a mini iPad with moving map.

Now working on a new direct air Intake on the lower cowl with a bellmouth.