Wednesday, September 5, 2012


It won't be long now until I apply power to the airplane and its associated subsystems. In the vernacular this is known as a "smoke test," perhaps for obvious reasons, perhaps not. The idea is, of course, that no smoke appears at all, and if it does, that it comes out of something relatively cheap, easy to replace, or if you're really lucky, both.

Because I'm getting close to the point where all of the smart little boxes get installed into the airplane, I thought it might be a good time to take the instrument panel parts out to be powder coated. For those not in the know, powder coating is:

...a type of coating that is applied as a free-flowing, dry powder. The main difference between a conventional liquid paint and a powder coating is that the powder coating does not require a solvent to keep the binder and filler parts in a liquid suspension form. The coating is typically applied electrostatically and is then cured under heat to allow it to flow and form a "skin". The powder may be a thermoplastic or a thermoset polymer. It is usually used to create a hard finish that is tougher than conventional paint. Powder coating is mainly used for coating of metals, such as household appliances, aluminium extrusions, and automobile and bicycle parts.
I want you to make note of a couple of things. First is that it "create[s] a hard finish that is tougher than conventional paint." I thought this would be desirable for the instrument panel. In retrospect, it would have been desirable in a lot of other places too, but it's too late for that. Second, note that it is "cured under heat."

Here's why that matters. When I stopped by the hangar to pick up the instrument panel pieces, I impulsively also grabbed the two steps that will be mounted outside the airplane to provide a means to climb up onto the wing in order to get into the plane. These steps will see rough duty, and they were already starting to rust just from sitting around in the humid hangar, so I thought I'd go ahead and get them coated too. Doing so would add $25 to the bill, but I thought it was worth it. I dropped them off last week and was told to expect a call midweek to let me know when they were done. Well, I got a call all right!

"Hey, I'm calling from the powder coating shop and I was wondering if there was something inside those steps you wanted powder coated. We put them in the oven and they're spewing clouds of smoke!"

Uh-oh! I had completely forgotten that Van's had me pour fuel tank sealant down into them to keep water out!! That stuff smells to high heaven anyway - I can't imagine the smell of it burning! Soooo, the steps didn't get powder coated. But the panel looks great!

I am in the middle of what has been described as the hardest part of the Skyview conversion, which is the routing of some wire bundles from the avionics bay back to the back end of the plane where the main computer will be installed. I pulled the biggest bundle through a few days ago, so all that was left was a pair of two wire bundles. These are the ones that I used heat shrink on to protect the little gold pins. I may have shared that I thought that idea would prove to be either brilliant or stupid and only time will tell.

It did.

It's not a great place to work from a comfort point-of-view.

But I managed to get both bundles through without breaking off any of the pins. The heat shrink was a brilliant idea!

No, really, I was thrilled! You just can't tell because the 90% humidity made working conditions pretty ugly.

So there it is! A lot of work for just eight wires, no?

I sure hope none of them smoke!

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