The wires in my hand are just for effect. They actually came out of my antique car when I foolishly decided that the warmed-up LT1 engine I had put in it didn't have near enough horsepower. With the
money I proceeded to spend on the followup engine I could have easily bought the firewall-forward kit for the airplane. We live and we learn (I hope). Money is shaping up to be a major player in how soon I can "slip the surly bonds of earth." The avionics and engine, which is what I will have left to buy after completion of the "finish" kit, represent more than half the total cost of the airplane.
Given that the airplane will have sophisticated avionics, autopilot, etc., I've always contemplated doing the wiring with a sense of dread. So far, the dread has been justified. I immediately discovered that some of the holes shown in the pictures in the build manual through which the wire bundles must pass were not present in my kit, owing, I suppose, to the slow pace of my build. During the time
lapse from when I order the sub-kit to when I actually get around to working on it, the kit has evolved. No mention of this is made in the build manual, so step one was to drill the missing 3/4-inch holes in the instrument shelf and three fuselage bulkheads. The left arrow in the picture shows an array of cooling holes that also aren't there, but I'll put off drilling those until I figure out what goes there.
The step drill shown worked well for these holes. BNC connectors and two fat wire bundles go through these, so the required snap bushings will be slit, placed over the wires, and snapped into the holes later.
The cooling fans were installed at this point. After hooking them up to 12 volts, I discovered that they blow in opposite directions relative to the fan housings, and one runs at a higher RPM than the other.
The Mothership said it's OK. Simply flip one over to get the correct direction and the slow one will probably come up to speed after it "loosens up." It would be so easy to replace one now rather than later, but I'll trust Van's.
The wire bundles and the three coax cables go over the rudder tube. A wire tray will be added later. The bolts holding the rudder tubes up must be loosened in order to allow the BNC connectors to pass above the tube. They still have to be forced through the gap.
In the picture at right, both wire bundles have been run. Various wires are identified and pulled out of the bundles as the bundles make their way aft through the various snap bushings, with some wires going all the way back to the tail cone area, others stopping at various locations.
The build manual stresses repeatedly to run each wire individually from the instrument shelf to its final destination. I didn't do it this way. Instead, I laid out each bundle on the shop floor and taped the end of each shorter wire to the main bundle, then ran the whole thing through the various Adel clamps and snap bushings. The sticks have been installed in order to run the wires for the push-to-talk switches. Issues with the sticks will be addressed in a separate post.
Much time was wasted removing snap bushings which the build manual had me install in various bulkheads and seat ribs. With the bushings in place, various wires with their already-installed connecters won't come close to fitting through the bushings, requiring that the bushings be removed and the wires run through the bare holes. The slit bushings can then be placed over the wires and finally snapped into the holes. The problem is that the already-installed bushings are difficult to reach and remove in the tight spaces. If I were building another airplane I wouldn't install any of the bushings in the fuselage until all wires are run. The build manual warns of this, but way too late.
Most of the builders who have gone before me agree that delaying the attachment of the tail cone is the smart thing to do (also not suggested in the build manual). This allows easy access to the rear
bulkhead and also makes it easy to turn the fuselage on its side. Having the fuselage on its side allows me to comfortably sit while routing the wires.
One of my students dropped by and offered to help with the fine adjustments.
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