Spent a few hours with John today to get help with a few things.
When I maidened the Falcon it had a strong right roll tendency, something quite challenging in 3-channel flight. Today he taught me how to twist a wing to bring it back into balance. The right wing needed to be twisted so that the trailing edge was down more as it was twisted a bit high (curious when measure it looked good, but there was a visible twist), causing a lift to correct the right roll. I am glad he did this for me as when I read his instructions I thought this was a more sever twisting. It was done with a few lead weights bags holding the wing, a slight twist in the correct position, as he ran the heat gun to tighten in the new twist. This is done on both sides and took very little pressure. Here I was imagining both my adult kids holding the wing and twisting it while I heated the cote... It took a few cycles and now it looks quite balanced. Cannot wait to get it in the air again, as correction of this flaw will make this a great flyer!
I also picked up the tail I designed and he built for me, fitting it and setting up the hinging. He cut out the elevator slot in the rudder as well. This is going to be a beautiful plane.
He agreed that I needed to put a little slabbing on the front where the original builder has stopped building, to give the cote a good surface to adhere to. I also need to continue the rib in the front two sections. Port side
Starboard side
He used an ultrasonic cutter (a specialized tool that of course an engineer who crafts rc planes at his skill level has) to remove the bulkhead that was behind the tank. Structurally it was unnecessary, and it was making positioning the fuel tank challenging.
To that end we also decided to abandon the idea of hard pointing the wing. On one hand there was just no good way to do the front securely as it wasn't built for it, and it is a vintage model designed for rubber banding. There was also the decision, which for some reason I had not considered, to fix the plastic top to the wing permanently. This solve several other small design issues. So I will be going with rubber bands along each side (no criss-cross because I will be flying the plastic top to the top of the wing permanently. I am really happy with these decisions as it simplifies so much BTW, I put a primer coat down on the plastic top. Darn it, forgot to also prime the cowl piece ...
The engine, when set to the firewall, sits so that the high speed needle and the cylinder head are hard up against the frame, as the firewall install inside the fuse. I also cut a 1/8" plywood backing the size of the Dave Brown round engine mount to bring it out a little to clear. I epoxied that to the firewall, which by the way has the "right-and-down" P-factor built in. I will need to drill access thru the plastic cowl to access the glow plug, but may have to make it much bigger to clear the cylinder head. I am installing the engine with the cylinder to starboard, exhaust straight down. This may change ... The plastic cowl has a large gap and I may rotate it to balance everything out. We'll have to see how it all fits first.
My next step will be to install the tail assembly, template out the cote work and do the cote (going olive drab), install the engine, control rods/sheaths/horns. I need to get a cutting compass to make rondels, and I have a great idea for the wing wires
I really hope I do will with the cote work, because this will be a beautiful plane!
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