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Monday, October 22, 2012

Extra Innings

Ok, even though I was raised in a baseball family, I'm a football guy. It's just wrong that the World Series now extends into November when football is going on. This time of year is for things like "Montana drops back to pass... Young is looking for Rice..."


But even though it was raining it didn't get as cold as fast as I thought... and I had some time... so......

 

The latest change to the aft cockpit manual shows the pitch trim changing, with the actuator now having a double bracket. I took mine apart, made a second bracket and installed it. But they must have changed something in the design because it changed the geometry, and it ended up rubbing against the elevator pushrod tube, so after spending a couple days installing it I remembered the old NASA saying: "Better is the enemy of best.", which also means "If it ain't broke, don't fix it.", and I undid the double mod.




Next was to make the hull doubler from some 6061, and drop it off at APC.




It was suggested I change the AN3 bolt for the tailwheel retract cable to an AN4, and add a bushing. Done.





Some concern also came up that the tailwheel bumper might actually cause a problem, since it makes the tailwheel hang lower, and it might catch a wave, snapping the extension cable. Good point, and I removed the bumper, and filled the holes with 6-8 rivets. 




Remember the hunk of foam I added way back when to keep drafts out? Problem is when the tail comes up out of the water a little flows back up the tube, and could be caught by the foam, leading to corrosion. A big stick helped shove the foam out of a small hole.





Here we go again. A to-do list for the turtledeck mate.




Since it's cold let's get the heater going. The standard PA heater is in the front cockpit ahead of the rudder pedals, but it requires tubing to be run from near the cluster bracket all the way up to the front, through the cockpit. It adds weight, and there's just something about having hot coolant underfoot in the cockpit that made me nervous.

Another alternative is to mount the heater from Recreational Mobility on the boom tube in the baggage compartment. I'm told most of the drafts come from up the boom tube and thru the aileron torque tube fairing overhead, so it makes sense to have the heater back there. Yes, it will eat into the available space in the baggage compartment a bit, but I'm learning kitbuilding is a series of compromises.





More hacking, making room for the fuel and electrical runs in the front of the pylon, and the heater hose in the back.



Since I've got the turtledeck out, let's pretend to make some windows. They'll get cut last during final assembly. 




Trace the outline of the windows, then draw another line 1" inside.  Trim, align 3" back and 4" up from the front of the TD.






Spend some time checking and double checking the alignment, and redraw the lines a few times. Or more.






"Back when" I ran the wing nav light wiring inside some silicone tubing, and it was a royal pain. While it worked, in the back of my mind I've been worried what might happen if I had to replace the wiring for some reason. I decided to use a larger diameter for the tail light, but that was a pain since the tubing was heavy, smashed flat, and curled up. I started to heat the tubing and it straightened out fine, but after spending an hour and only getting a foot done I was rapidly getting frustrated.




Then I remembered this stuff called "Bilge tubing". Lightweight, easy to straighten out, it slipped into  the boom tube in seconds, and getting the wiring thru didn't take much longer. Next year I'll replace the tubing in the wing with it.









I've been putting off the fuel system. I wanted to have a fuel shutoff at the tank outlet before the fuel pumps, and there needs to be a gascolator or filter before them. When I picked up the aluminum tank a couple years ago Paige was kind enough to give me a handmade fuel strainer tapped into a brass barbed fitting, but all I could find was a fuel shutoff tapped for threaded fittings. Which meant I'd have to go from tank-hose-shutoff-hose-filter/gascolator-hose-pumps. Lots of fittings, lots of hoses, lots of stuff that needed to be secured against vibration. I didn't like that. I wanted to go directly tank-shutoff-hose-filter/gascolator.

I couldn't pull the strainer out of the fitting, and frustrated I put it in a vise and wiggled. Eventually it popped right out. 



It was 0.02" too big for the fitting, so I borrowed JR's lathe and carefully turned it down. 



It wasn't a perfect fit, but I into a corner where it wasn't quite tight enough for me to be happy, but too tight to remove, and I didn't want to hammer it too hard and risk breaking it.




Stopping by Scott's shop, he judged that it was comfortably tight and secure, but also pulled out some Pro-Seal. I left it to set-up while I was gone on this trip.

 


Guess what Gordon finished?








I miss being warm.



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