« Archives in December, 2007


1.5 hours.
Trimmed wingtips and got the LED nav light/landing light combo installed in the left wingtip. Mostly. Too many chickens and too many eggs. What I got done was cutting the holes and temp-installing the LED nav light board and the landing light bracket in the wingtip. No paint or anything fancy, and it’s not really that difficult of an install, but as usual, never having done it before, it took a lot more time than I think is probably necessary. I did get the wingtip edges trimmed so they clear the ailerons and they fit nicely into the wing skins. Once the strobes go in, I have to make the wingtip lenses out of the plexi that came in the kit, but once I’ve done those, I’m gonna call this done until it’s time to actually wire the wings and install the wingtips, which will happen a lot later. OH, and good news. The tanks are sealed! The balloons lasted two days without any appreciable deflation, so it looks like my splotch job with the proseal worked.
But back to the wingtips. Eventually, the side of the wingtip cutout holding the nav/landing lights will get covered with red/green scotchbrite tape, if I can find the right size/color.
Now the only things standing in the way of the wings being done is pitot/AOA plumbing and riveting on the bottom skin, which will also get deferred until I figure out what to do about an autopilot. Ideally, I’ll mount the servo in the right wing to counterbalance my fat ass when i”m flying solo, but if push comes to shove, I can mount it on the end of the wing and run a longer control rod, later, after it flies even.
So here’s the tip, with a sharpie mark on it, in an attempt to actually measure where the light is going to go.

Just a quick lineup test of the right wingtip mocked up to the wing to test the trim job. Looks good to me.

This is one of the CreativAir nav/landing light setups. The metal bits hold an MR16 lamp and the red bit with the LED clusters on it goes outside on the cutout.

Here it is in place. The landing light aim is adjusted by long bolts which keep the lights aimed by spring tension. Simple, neat, easy. Props to Bill Von Dane for this setup.

Cross your fingers

1.5 hours.
Testing the tanks. I made capped lines for the vent lines by squeezing the end of a section of 1/4″ tubing in the hand seamer with a regular AN fitting on the other to connect to the vent line nipple. Got to use my new tube bender, cutter and flare tool. Sixty bucks off eBay. Then I put a balloon in an AN fitting and that over the fuel line fitting with some vaseline on the thread, for a decent seal without ripping the balloon. Then forced air in the fuel drains to inflate the balloons and gaffer tape over those holes before the air ran out and the balloons deflated. I then measured 2 marks on each balloon, wrote down the distances between them, and the time. If the balloons stay inflated over the course of the day, and the distance between the marks stays roughly the same but doesn’t decrease overall, then my tanks are sealed. I’m expecting those distances to fluctuate with temperature somewhat, but a leak should make itself evident within 48 hours.
Meanwhile, I’m waiting for FedEx, who is theoretically showing up with my wingtip light kit and strobe kit at about 1:30. I’ve gotten the wingtips down out of the rafters, so I’m thinking about glassing in the Archer antenna and making the doubler strips. I suppose I could just do CS4-4 rivets, but I’m not into drilling those out eveyr time I need to change a landing light bulb or troubleshoot the VOR antenna. Either way, I need to do the wingtip ribs.
I’m also trying to decide whether or not to buy the Trio avionics autopilot now so I can install it in the wing and be done with it. OTOH, if I don’t close the wing skins until much later, I can worry about it then.

Sealed the tanks.

5 hours.
Prosealed the access plates and fuel senders to the tanks today. And yes, I’m counting setup, pondering, and cleanup time. The last time I messed with the toxic nougat, it was the rudder, and the actual sealing properties weren’t as important as just gluing the bits together so they didn’t shift under stress from riveting. This is the real deal. I made damn sure every surface to get gooed was cleaned thoroughly with MEK, and that the tankside surface of the access plate was scuffed up beforehand. Access plate. That’s a good one. If you slather a ring of this crap around the outside of it and screw it down, you ain’t accessing anything in the tank for a long long time. Following the advice on VAF, which made sense to me, I discarded both the cork rings for the access plate and the rubber gaskets that came with the fuel senders. Supposedly Prosealing it will give you a much better seal and the cork gaskets tend to deteriorate over time and eventually leak fuel. This I believe; when I was a kid, we had gaskets on our boat tanks made of the same stuff and they leaked like a bastard. I just hope they seal, because if they don’t, it’s going to be a very, very bad day, which could set me back several hours if I have to somehow get those plates off and fix/modify anything inside there.
The blogware’s probably going to cut off the right hand side, but here they are, sealed and curing.

As you can see, I haven’t dialed in that ‘beautiful proseal job’ look yet. I’m just hoping it works. I made sure there was enough goo, liberally applied on the surfaces in question. I even put some around where the weld for the sender insulator is. You never know. But I bet I wind up sealing that over once I’ve got a wire on it. that’s no big deal, I know how I’m going to do that: Hook the shop-vac up to an adapter going into the fuel fill hole to provide negative pressure and daub a wad of the gray all around that fitting. Hopefully Stewart-Warner has thought of and made the unit airtight already.

Things to finish wings

This is more of a checklist for me than a report of actual work done, but here’s what i need to do to finish the wings:
Seal/test fuel tanks
Install nav antenna in wingtip (on the way from AC Spruce)
Install nav/landing lights in wingtips (on the way from CreativAir)
Run power and antenna wires from wingtips through conduits to wing roots
Run pitot/AOA plumbing to wing root from pitot mast location (order this from SafeAir)
Make wingtip connectors for lights/antenna.
Figure out whether or not to close up the wings, and if so, install pitot/AOA mast and probe.
Once these things are done, I believe the wings are finished. Then I have to store them in the garage and build a wooden cage around them so they don’t get bashed by various comings and goings for laundry and yardwork. This can be done by a few 2×4’s framed outward from the wall and covered with a thin sheet of plywood.

So now what.

2 hours.
Finally got what I needed from Spruce to finish the wing conduits, and those are now done. Proper aluminum Adel clamps all around, no interference with the pushrod. Also temp-installed the fuel senders. After a lot of agonizing about how to do this, I decided to bag the fuel return lines for now. If I get into a situation where I need a new engine and that engine needs a fuel return, I’ll pull the tanks off and plumb it then. I could do it now, but why? I guess the advantage is being prepared for an eventuality, but it’s still going to be a lot of extra work, and those fittings are pricey, from either Van’s or Spruce. And another thing: trying to correlate Van’s AN SPACER 6D with a spruce part number was nigh impossible. Not only that, I’m not sure what sizes to use for a return line. The Eggenfellner site says to use 5/16, the fuel feed line is 3/8’s so returns of that size would make sense, but a lot of guys on VAF would have done it 1/4 if they had to do it again. I don’t need it that badly, so screw it. Moving on.
I’ve ordered strobes, nav, and landing lights. I went with CreativAir’s LED nav light and 75w halogen landing light combo, and a 60w/6 way strobe package from Strobeguy. I also got the Archer nav antenna from spruce. All this crap is going to go into the wings and so is the wiring. I still have to proseal the fuel stuff and test the tanks (dread), but wiring the antennae, strobes, and lights should be fun, and not in the usual snarky way I say things are fun. I’m looking forward to it.
What this means is that I can’t yet shove the wings into a dark corner for a long time and go full tilt on the fuse. I need all that above-mentioned crap to finish up the wings, but if I can get the tanks sealed, then maybe I can save that wingtip stuff for much, much later. I’m not worried; I’ve got a 3/4″ wide conduit down each wing. Wiring wingtip goodies is going to be a snap.
This is the PVC conduit running along the pushrod. No clearance issues here.

Top of the pushrod’s arc. No way is this going to clang.

This is the conduit sticking out way past where it should at the wing root. I’ll trim it, eventually. The red crap around the edge of the lightening hole is irrigation drip tubing, split down one side and fit over the edge so the pushrod doesn’t bash around and ding up the primer.

A look at the tank access plate, with the sender temp-installed. The little blue AN fitting below toward the leading edge is for the vent line. The two clecoes on each side are holding on to an anti-rotation bracket that slips over the tubing nut on the other side of the plate where the big blue fitting is. That’s where the fuel pickup is. That will get prosealed and riveted.

Wings moving along.

4 hours.
Finished dimpling bottom wing skins and got the access doors done. This did not go perfectly. I didn’t set the clutch properly on my powered screwdriver, so I snapped one of the 6/32 screws for the forward edge of the left outboard access door. No big deal, except I don’t have a replacement 6/32 K1000. I wish I’d done this last week before I put in my order from Spruce. I’m not ordering a lone bloody platenut. I was going to wait until I messed something else up, but that didn’t take long; I did it as soon as I got to the fuel senders. To make the fuel float work, you’re supposed to bend the float wire 90 degrees about 3″ back from the float, then cut the wire off 3″ down from the bend. This insures your float goes all the way to the top and bottom of the tank. Well, what they don’t tell you anywhere on the plans or the float instructions is that you’re supposed to leave enough wire on the end to bend 90 degrees and stick it through the hole in the sender’s pivot. This keeps your float from flopping around. I found this out on VAF after I’d cut the wire. I only used 1/8″ for this bend, so it might still work just fine. If that’s not cool, I can make a new float wire out of extra piano hinge, which someone else did.
I’m also not sure what type of bolts/screws to use when fastening the sender to the access plate on the tank. Drawing 16A has all the fuel tank details, but I can’t find that tidbit anywhere.
The other thing I did was start pulling some pieces out of the tailcone and clecoing/leaning/stowing them where they’re supposed to go on the airplane. It saves some time looking for stuff, and reduces some of the psychological impact of such a huge pile of parts.

Wing conduit, and a couple of fiddly bits.

4 hours.
Spent a whole lot of time figuring out the best way to run PVC conduit down the big lightening holes in the left wing today. I’m sort of doing the Mickey Coggins method, but probably not as well or as precisely. I made a bunch of L brackets out of a forward HS spar I’d ordered a while back when I thought I’d have to replace most of my HS, then clecoed Adel (fake ones, from Ace) to them attached to the 3/4″ PVC conduit. Lots of trial and error, moving things into position with various clamps and such, testing for fit and interference with the bellcranks, figuring out which ribs to clamp them to. Once I got a combination of bracket, Adel clamp and conduit that sat well and gave maximum clearance to the bellcrank, I clamped it down and marked the position on the rib. Then I made a template out of some scrap, which made it easy to determine the bracket location on the remaining ribs. Of course, here I am, trying to hold three pieces of metal in position with the intent of putting a drill bit through them when I grasp the fact that I’m doing it the hard way, as usual. The little 1″ cleco clamps you get with the tool set are like extra hands in a situation like this, and I’m a dumbass for not realizing it earlier. Clamp on the template, clamp the bracket, drill the bracket, move on to the next one. I primed the brackets, the outside of the aileron pushrods, and the pitot mast while I was at it, then riveted on the left wing brackets. Right wing brackets are in position, I should be able to deburr, prime, and rivet them into position tomorrow. Then, I wait for a bunch of AN hardware to show up from Spruce.
Also, my package from MSC showed up. Should be a new Burraway, some spare blades, and something else I forgot about.

Some ugliness.

Yesterday when Dan was here, he pointed out the ham-fisted way the left HS inboard ribs were put together. He was right. It’s ugly. Two rivets are close to minimum edge distance, if not over the line, and now that I see that little section of the HS (Months later), it looks like a team of chimps went to work on it with socks full of ball bearings. But I so want to be done with the empennage. I sent photos to Van’s, and they said yeah, it’s ugly, but it’s ‘hard to imagine this will cause any problems structurally.’ So I’m going to move on, and cover it up with the empennage fairing when the time comes. If it continues to drive me nuts, like some aluminum telltale heart pinging away aft of the baggage compartment, I’ll fix it by replacing the left HS inboard ribs.

Oh, one more thing.

Yesterday, my .093 Burraway developed an oscillation, due to me pullingit out of a hole at the wrong angle. In the foolish attempt to bend it back into shape, I snapped the shank right in half. That was a big ‘Oh frak’ and not the Galactica pronunciation either. Cost is $TBD in treasure, and a nice gouge in the base of my thumb from the snapped end in blood.

TC visit today.

4 hours.
Dan C and Scott F stopped by today and we went over the progress to date. It worked out great! The only squawks were some bolts without enough threads showing, some with too many, and a question of whether or not the left inboard HS ribs are outside minimums on a couple of rivets, and a suggestion on how to do the flap hinge pins, which brings us to today’s actual work.
Afterwards, we grabbed a bite to eat at Spitfire, then I watched Scott’s IO-390 powered RV7A hop into the sky like an ICBM. Back home, I farted around for a while, trying to decide what to do first. I did all the bolt squawks on the emp, then put the emp parts up in the attic, awaiting Van’s word on the rivet status of the HS rib. Then I did the flap hinges. I cut out 2 eyelets on the flap and one on the wing and ran the hinge pins in from the center. I bent them back and fastened them to the flap brace by means of a small plate and a CS4-4 rivet. Probably coulda just safety wired them below the wing, but this way the pin ends are tucked away out of sight. I did the left wing, and i’m almost done with the right wing, just need to make a hold-down plate for the pins and the flaps they izz installed.
Still waiting on my Dynon pitot/AOA probe.