Look at the wiring in any car and you’ll see a rainbow of colors. Look at most any airplane and you’ll see flowing currents of white Tefzel wire.
Tefzel wire, the standard for aerospace applications due to its heat, chemical, and abrasion resistance, is also available in colors, but it is expensive and typically sold by the roll, not the foot.
My Sonex had white wires. I applied neatly printed numbered labels to their ends to identify their purpose. The numbers proved small and hard to read in dark places, or outside the focal range of my astigmatic eyes. It took far too long for the idea of painting white Tefzel wire colors to germinate, but it did, and with this sharing you benefit from my late bloom. (It seems I come to most everything late; hopefully my funeral will be no exception.)
There is little reason to paint the entire length of a wire — it is the ends that matter most. When installing, removing, or troubleshooting a circuit, color-coded ends are extremely helpful. Fully painted wires may be helpful if you anticipate tapping into a wire mid-stream sometime in the future.
Record the color used for each circuit on the electrical schematic. There is no point in color-coding wires if their function is not recorded for future reference.
Schmart, very schmart. This idea is long overdue–kudos for mentioning it. Tracing the labyrinthine wire bundle under the panel or in the exhaust and oil stained cowling on a hot, sunny day is true torture. Worse on cold and rainy days or evenings when you know there’s a loose wire or intermittent connection you want to find and eliminate. Only rapped knuckles and bleeding fingers will do the job first time if you can locate the badass wire or connection. Colour codings should save 85% of the detective time. Good call.
I did something similar on my homebuilt aircraft. I used a permanent marker and made a series of dots on the ends of individual wires. Some had 5 dots, some 4 and so on. Then made a legend to refer to. I’m not waiting for paint to dry and it’s messy used inside the aircraft. (overspray)
Can colored shrink-tube be used or is there a flame hazard?
…and they are probably more durable than paint
I looked at several ID options, but decided to ante up for colored Tefzel. I agree that the ends are generally what matters most, but I have seen far too many cases where wires get cut mid-run either accidentally or or intentionally and knowing the circuit ID mid-run is occasionally useful.
And the cost difference isn’t great. At the moment, 24 gauge Tefzel at Aircraft Spruce is 51 cents/foot for white and both black and blue are cheaper at 45 and 48 cents/foot, respectively. The most expensive color is yellow at 57 cents/foot, so not that much different.
Sure, you will have more left over wire when using colors rather than just white, but I estimated my wire lengths fairly closely and bought pretty close to what I needed and didn’t have that much wire left over. I doubt using colors rather than white cost me more than $50 extra which is not much in the scheme of things. Buying 5 cans of colored spray paint costs nearly that much and spraying all of the wire ends is a lot more headache than just using colored wire.
This ranks up there with other forehead-slapping “Now why didn’t *I* think of that!?” moments I’ve had during building. Thanks for sharing another clever and useful idea!