« Archives in December, 2010

On. The. Gear!

10 hours.

Over a couple of days that is. This week I tucked into wiring. I had to drill some new grommet holes in the baggage bulkhead on each side so I could slip some fat strobe wires up one side, and some fat RG400 coaxial cable down the other. Performing this task is difficult. I don’t have a large drill bit that screws into my 90 degree drill, so I had to make do with a countersink. A countersink can, in a pinch, be used as a drill bit. Drill your 1/8″ pilot hole, then push the countersink all the way through. Hole gonna need some cleanup, but that’s OK. I finished up running the strobe and coax for the ELT and tail strobe, along with power wires, then ran two lengths of RG400 cable aft for the GPS antennae up the left side after making a couple of new holes in the baggage bulkhead for some grommets.. This should take care of the eventual two GPS’s, the one in the MGL Odyssey and the one in the GNS430W. Yes, I’m going to get a GNS430W, because it contains 3 pieces of very necessary equipment in one box. On the other side, I ran two high voltage strobe cables and the strobe powerpack and tail light power wires.

I had some leftover coaxial so I ran it through the spar to a spot picked out for the COMM antenna on the left side under the seat panel. When the new load of coax comes in I’ll run the wire for the transponder antenna and reserve a healthy length of wire for the run down the left wing to the Archer antenna.

Not much to look at right now, but this will eventually get cleaned up, fully routed, and fully dressed.

But the fanfrakkingtastic thing is this:
I got the plane on the landing gear today!

To do this, I rolled out my trusty engine hoist.

It’s hard to take a self-portrait with an iPhone 3G, but this is me, positioning the hoist in order to lift the ship high enough to get the gear leg into the tube on the engine mount.

Lifted off the ground with one gear leg on. Judge me by my size, do you?

The plane supported only by its own landing gear.

From the side…

So now I have to cut a couple more holes in the firewall for electrical goodies, but the good part is, I’ve got a rolling airframe on which to hang the engine, which should be done soon. On the down side, it’ll be harder to get in and out, so I’ll have to come up with some kind of platform to make that easier. I have to go back down the Jeffries Tube a couple of times to clean up some wiring, but not too much work back there. Next is running battery and alternator cables, figuring out the wiring busses, actually choosing switchgear, and finalizing the panel design.

The Jeffries Tube.

3 hours.

In Star Trek, the Jeffries Tube (named after a member of the original series’ production crew) is a long, narrow tunnel from the engine room to the warp drive nacelles of the USS Enterprise. On the RV-7, it’s the space behind the baggage compartment going all the way down the tailcone to the 3rd-to-last bulkhead. Working down there really does make wish such things as aircraft elves existed. Unfortunately, they don’t, so I had to crawl down the Jeffries Tube to drill holes in bulkheads for wiring grommets, carrying a big cordless drill, a bit for the pilot hole, a bit for the grommets, a deburring tool, and the grommets themselves. I was able to get the grommets in and start the wiring run for the strobe cable and tail light power wire. It’s a slow process, and being mildly claustrophobic and crammed into a metal tube reminded me of my recent unsettling, yet action-packed U-boat dreams. I’m going to be spending a lot of time down there. I also have to drill grommet holes for the ELT coaxial cable and set up the wire stays for everything. I’m trying to avoid drilling more holes in the longerons and j-stringers, but I do have some adhesive-backed cable tie holders that will need to be placed.

As an aside, I finished the lower empennage fairing. These two stupid pieces of metal are supposed to have a rubber seal on them, but there’s no way that’s going to fit. Also, there’s no point in making these things removable, so I riveted them on. So now I have a 1/16 to 1/32 gap along the horizontal stabilizer at the root. So I lose a knot. Big deal. If it concerns me later, I’ll create a proper fiberglass lower fairing. Speaking of fiberglass, I got the empennage tips riveted on. they’ll need a coat of primer/paint, but they’re done.

Also, yesterday I got a call from Tim at Tim’s aircraft. My spam filter de-rezzed his pdf of the engine repair estimate, but I got a new one from him. Nearly eleven grand. Ouch. But now I have nitrided steel cylinders instead of that godawful cermichrome and it’s going back together as soon as the magnetos come back from the specialty shop. I just hope he doesn’t flinch at installing the AFP fuel injection system. But what that means, brothers and sisters, is that I’ll probably be hanging the engine in the not too distant future. At this point it’s now time to get down and dirty with the remaining amounts of money and see if there’s enough for avionics, remaining FWF, interior package, taxes, training, and hangar rental at my phase 1 airport.

More emp tips and the strobe head.

4 hours.

You know by now that fiberglass is not my favorite medium in which to create airborne works of art. Mostly it’s the mess, but the big minus is the cure time. I filled the ends of the empennage tips with foam, laid up some fiberglass on each side to stiffen it, then slathered on a nice frosting of micro. I had to take another run at the micro to fill the low spots, but this time I mixed it a little wet. Of course, this necessitates putting the pieces in a position that will allow the filler to flow out flat along the backside, like so:

This tree, cobbled together with clamps, tongue depressors, and scrap angle, allowed the filler to behave as if it was cast in a mold. There’s still a modicum of shaping after this, but these are nearly done.

But I had to do something else while this was curing, so I tackled the thing I know I have the resources for. A while back, I verified that the strobe unit worked. Now it was time to stick it in the plane. I’m going to worry about wire runs later, but I mounted it just behind the baggage comparment bulkhead on the passenger’s side. This is a fairly common location, and will do the job nicely. But I’m out of practice with metal. I went through three plates before I got one that fit right. There are two pieces of angle a little wider than the strobe head, fixed to the J-stringers between the longeron and the floor. Drilling them to the J-stringers was not fun, and neither was riveting them. But they did eventually go in. Here’s a shot of one of the angles clecoed in:

And this with everything assembled and riveted:

Foam arrived, finally.

1.5 hours.

Cut and glassed in the emp tip foam inserts. This damned foam took nearly a month for Aircraft Spruce to get it to my house. It was backordered, then backordered again, and I finally got it today. They sent me a 2×4′ sheet of it too, and I’m pretty sure I ordered a lot less of it. Oh well.

This was easy enough, cut out some foam bits that fill the shape of the fiberglass tips, closing them off to outside elements. Mostly. I applied fiberglass and foam with the tips clecoed on so when the resin dries, I can pull them off and the tips will stay the shape they where when clecoed on. A couple of layups on the inside of the foam block and some micro filler frosting on the outside and those will be done. Then I don’t have to see the empennage again for a while.

Since I had some resin in the pot, I used up all the rest of my cut scraps to glass in the Archer VOR antenna in the wingtip, something I’d been planning to do for a long time but never got around to it. I did two layups on that, which should be enough to hold it in place, it’s not structural, just something to keep the antenna from flopping around in the wingtip. Another thing done.