Side Splitting Fun!

After a few days of avoiding the late-August heat and humidity, it was a relief to have a day in the mid-70s. It's been pretty hot out in the hangar so I've been spending my time on low-stress jobs like priming the longerons and trying to figure out how to install the Dynon D-6 in the flying airplane. I've finally developed a plan and ordered the parts to plumb the unit into the existing pitot/static and electrical systems, but I'm still flummoxed on the question as to where to mount the external compass module. Just figuring out which pieces of pitot/static plumbing supplies I needed and how to find them on the vast AircraftSpruce.com website took the better part of two days. Well, not "days" in the traditional 24 hour sense, or even the 8 - 10 hour work day sense. I mean two days in the I-get-about-an-hour-a-day-to-spend-on-stuff-like-this days.

All that's done now, except for the waiting for the FedEx Ground truck to deliver my stuff. That's not until next week, so I braved the temperate temperatures and high winds this afternoon to go out to the hangar and cut the spar slots in the fuselage side skins. The directions suggest the use of tin snips for the cuts, but I've always found snips to be somewhat abusive to the edges of the cuts. Or I'm just using them wrong. Which of those is the actual cause is moot, of course, since 'tis yours truly what has to make the cuts, right? Right!  I thought I'd try out my Harbor Freight nibbler instead. Clever as I am, I also thought I'd try it out on a piece of scrap metal first. My opinion after said test is that the nibbler makes a straighter, cleaner cut, although I did discover that it likes to scuff up the surface of the edge. I figured a layer of protective masking tape would solve that issue, though.

Step one: remove the pesky blue plastic.

Step two: clamp down the skins. The wind was 14 gusting 20, and the 20 knot gusts were threatening to blow the skins right off of the workbench.

Step three: make very sure that I'm cutting away on the correct side of the slot. My experience with the incorrectly bent longeron and my even more traumatic experience as a spectacularly failed orthopedic amputation surgeon encouraged me to be extremely diligent in marking the correct part of the skin to be removed. Much like cutting off the wrong leg, there's no fixing a mistake here!

Step four: see if I can find a perfectly sized rectangular drill bit to remove the metal in one shot. Failing that, use a nice, fat round bit to create a hole for the nibbler to start nibbling in.

Step five: lay down a prophylactic (oh, get over it. That word has a much more generalized meaning than what you're thinking of) layer of tape.

Step six: nibble, nibble, nibble.

The nibbler is also very good at trimming the edges after the first rough cut.

And there it is!

It was a waste of time since it will have to come back off, but I couldn't resist tacking the side skin on to see how it looked.

As I was looking through the top row of holes in the skin and seeing but raw longeron through them, I figured one didn't need to possess the prognosticative powers of the perspicaciously prescient Nostradamus to see what's coming soon: a whole lotta match drilling.

Oh goody.