Tuesday, June 29, 2010

Stringing Anti-Drag Wires

Yesterday I decided that the butt ribs can wait for more patience and installed the tip compression strut yesterday. Strangely, despite the last noserib sliding between the compression strut and the spar, there's no shim to adjust for the slight (0.010 inch) difference of one side of the compression strut to the other - It's just bolted down. (This is why to NEVER toss the old anything in restoration - I hauled the old cracked spar out of the attic and stood at the top of the ladder going "Really? Really? I didn't lose a shim, it's just there isn't one?")

Today I strung the drag and anti-drag wires starting at the tip, and stopped to contemplate the first bay. The drag and anti-drag wires go through the wing tank, with a foot of thick clear plastic tube wrapped around each to prevent chafing against the tank. The tubes I currently have were pulled off so I could remove corrosion and zinc chromate all the wires - and I appear to have lost two, while the other two are discolored dark brown where the friction tape secured them. I'll have to figure out where to get more before I put the gas tank in and string those two wires. (Then I'll have to redo the right wing, too, as they're strung sans tube or gas tank install.)

I took time out for a run to Reeve Air Motive to get more AN-3 bolts for the rear spar attach bracket, and a necessary detour to sit in my plane and make airplane noises, promising her she'll soon have wings. Then back to work, only to discover the rear spar actually takes AN-4 bolts; I was looking at the wrong end of a misdrilled hole that needs to be reamed out. I'm going to have extra hardware when this is done - but better to have 5 too many than 1 too few!

Then I got to checking the front spar attach bracket - and that, like the right wing, is just a little off. So tomorrow, sanding the end in hundredths of an inch until it's juuuust right, varnishing, reaming, varnishing bolts as they go in so the fresh wood inside is protected, and attaching those. If I'm wise enough, I'll remember that one end of the butt-end compression strut overlaps with the rear spar attach bracket (That one is shimmed! And I know exactly where that shim is!) so I don't have to try to get the bolt back out after it's varnished in place. Lord, help me look at the checklist I'm writing tonight!

And I shall repeat to myself until I believe it: "Finding new mistakes and errors to correct is progress!"

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