Sunday, September 14, 2008

Listening to voices


In aviation, it's not uncommon to hear voices.

Rare is the time I'm flying when I don't hear the sound of my first flight instructor's voice.

Airplane building is like that, too. I hear voices all the time, and it's a good thing because I think the RV-7A I'm building will be a better airplane because of it. Sometimes I hear the voice of Ken Scott at Van's (although it comes through as an e-mail), urging me to "build on" when I think it's better to build some part again.

Other times the voice says something entirely different. Yesterday was one of those times.

On Thursday, after 7 hours of work, I had convinced myself that the canopy windscreen fairing was shaped about as well as could be. But part of me had doubts and the voices wouldn't stop on Friday. So by Saturday morning, I knew what I had to do.

"You have to be a little more aggressive in sanding," Doug Weiler's voice said to me yesterday, repeating what the president of the Minnesota Wing of Van's Air Force said to me in person a few weeks ago at the hangar.

"When you find yourself saying 'I guess that's good enough even though I'm not that happy with it,' it's time to take a break and think about it some more," RV-10 builder David Maib had said to me a week ago... and again, by proxy (me), yesterday.

When I arrived at the hangar yesterday, I opened up an old issue of Kitplanes while I munched down the Big Mac and Coke. It was the June 2007 issue, one about working with composites and, specifically, one about a canopy windscreen fairing on an RV-10.

The advice was comforting -- you can fix anything that isn't right with fiberglass, for example -- and instructive. The builder had used 14 short pieces of fiberglass instead of one or two long pieces. I had used about 3 on previous layups and I didn't like the result much. I had, over the last week or so, sanded well into those layups and I had already decided to do one final layer of fiberglass, having shaped the radius.

By the time I finished reading the article, and with the voices seeming to scream at me, I knew what I had to do: a better job.

So I put the low-grit sandpaper back on the shaping tool and went back to work. Instead of trying to do the entire length of the radius at once, I concentrated on getting one small area just the way I liked it, and expanding it from there. Eventually, it was done, and I liked it.

It may still not be Oshkosh show plane quality -- or even the RV next door quality -- but I'm finally happy with it.

Then I layed down the final layer of fiberglass, having realized that I really hadn't been cutting the fiberglass strips on a 45 degree angle and finding that, yes, it's a lot easier when you do (the fiberglass doesn't come unweaved). I layed down short strips, taking care to tuck it right up to the tape that marks the top edge of the fairing (the fiberglass there will be sanded down level with the tape, and then the tape will be removed, hopefully revealing a nice tapered edge).

When I put peel ply on it, I felt for the first time that I understood fiberglassing technique better, and vowed -- as I have for 7 years -- that the next RV airplane I build will be even better.

When I finished, I heard a voice say, "nice job, Bob."

That one was mine.

2 comments:

  1. That message - in any voice - is good to hear.

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  2. After spending the past 2 months on my -7 canopy, I feel your pain! Keep on sanding! The best thing about fiberglass/canopy work is that it's not done until you paint it. If you decide six months from now that you can make it a little nicer, there's nothing stopping you from laying another layer of glass or squeegee-ing more filler...

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