Check, too, that the wings are level in both upright and inverted flight. The "different on insides and outsides" could be from esoteric and subtle P-factor and torque effects from the prop -- or you could have a plain old warp in the wing, or tweaked flaps, that's got the plane rolled tip-down in upright flight and tip-up inverted.
If you have a helper that you can trust, have them watch the plane while you fly dead-level laps both upright and inverted. This works best if you can fly laps at five feet, but if they've got a good enough eye it works at any altitude. They should be looking for the wings being level in both attitudes (if you're flying at handle height) or at least parallel to the lines (if you're flying high). If the tip is down in both upright and inverted, then you're tip-heavy. If the tip is down upright, and up (or less down) in inverted, then you're rolling to outside while upright, and you need to tweak your outboard flap down a bit. If the tip is down inverted, and up (or less down) upright, then you're rolling to the inside while upright, and you need to tweak the outboard flap up a bit.
If you don't have a helper, and if you can do so without crashing, then hold the handle up at eye height in level flight and sight along the wing. If it's level (assuming no dihedral) then your view of the wing should be blocked by the tip. If you can see the top of the wing in level flight and the bottom in level-inverted, then you don't have enough tip weight. If visa-versa, then you have too much. If you can see the top of the wing in both level and inverted, then you're rolling in while upright, and you need to tweak the flaps as above. If you can see the bottom of the wing in both level and inverted, then you're rolling in while inverted, and you need to tweak the flaps as above.
I recently helped a friend trim a plane. When I started with the "is it rolled" stuff I could see the bottom of the wing to the fuselage in level flight -- and the bottom of the outside wing in inverted flight. Flaps were tweaked and weight adding immediately after I landed and calmed down.
Inexperienced as I may be, I've found it useful to start serious trimming with a bit "too much" tip weight -- that way, if you've got serious problems with wings not level, or with leadouts grossly wrong, the excessive hinging will let you keep your airplane long enough to get everything else sorted out. This may not be necessary if you're an expert -- but you'll get to expert quicker if you have planes to fly.
Topic: Another trimming quandry (Read 1440 times)