Prop safety-wiring

Tonight I finished safety wiring the prop attach bolts. I had previously wired two of the 6 bolts, but had left the others so I could move on with other tasks. At the time I was working towards a deadline – moving the fuselage to the airport – and didn’t want to spend more time on the task. The first two bolts had been a real pain, and I had redone the wiring several times before I was satisfied that it didn’t suck too badly.

For the remaining four bolts, I started by practicing with the thinnest safety wire I have, which is much easier to work with. After figuring out the routing, the length required, and any other relevant details, I switched to the large diameter wire and completed the task. The bolts are wired in pairs, and each bolt has a hole through the center where the wire passes. Because of the varied orientation of the bolts, each one presents a unique challenge in getting the wire through the hole. I was lucky that only one bolt needed loosening and reorienting, and I was able to get all the others to work without adjustment.

In the end I was quite happy with how it turned out, and found that a little practice and lots of patience definitely helps.

A pair of wired bolts. The wire acts as a fail safe in case the bolts vibrate lose and start backing off
Another pair of wired bolts

EarthX Battery

Before completing the aircraft wiring, I decided to switch to a Lithium battery, and EarthX seems to be the most popular brand for RV builders. The difference in weight between the original lead acid battery and the Lithium battery is substantial. I didn’t have the original battery specs, but it must be 3-4 times heavier than the Lithium battery. There are some other benefits too, such as a longer period of output, longer store of charge, and a battery health indicator output wire.

The EarthX 1200 series is an almost exact match in size. It’s slightly deeper, slightly narrower, and the top is shaped differently. The battery came with some foam to help make up for the narrower shape. I added a washer on each side to account for the wider shape, and added some aluminum strips with foam to the hold-down bar to ensure a snug and secure fit.

The battery terminals are basically the same, so once I had modified the hold down bar and charged the battery, it was ready to go.

Original Vans supplied battery. This is a few years old now.
Side by side comparison of Vans batttery (right) with EarthX battery (left)
Test fitting. Not the gap under the hold down bar
Added some aluminum strips and foam to the hold down bar
Final installment. Note, the ground is disconnected since I’m still running on ground power at this point