Poly-Stits Workshop

There are many skills in this world that are best taught and learned with hands-on instruction. No amount of dry spectographic and temperature detail in a textbook can best describe the right shade of glowing color that is best for hammering bar stock into a folded steel knife. No video can truly teach the feel of a ripe melon, or the smooth rhythm of a pass of a paint gun.

This weekend I was one of a class of four in a garage learning how to cover a fabric wing. We started with books describing both the Poly-Fiber and Ceconite processes, but it was up to us to crack them and read more in our own time. Instead, we spent most of our time with our hands on tools, being walked through recovering an aileron from a DC-3. (If you can recover that, with tapered chord and tight radius bends, wings and fuselage should be simple.)

I learned how to rib-stitch, how to avoid making mistakes, and how to fix the mistakes we made. If we didn't make the mistake, our patient instructor made them for us, so we could learn without fear on somebody else's plane! And like many things in life, if you understand the Why and the How, then the process is simple, but not easy. Fabric work is not complicated, but it does demand attention to detail and the occasional time spent standing there with cup of coffee in hand, plotting out how to accomplish the desired result.

Interestingly enough, this workshop drove home the point of increased expectations. I am rebuilding my plane to a far higher standard than she was originally built. When she came off the line in 1941, she had an expected lifespan of five years. Now, I am expecting the covering I put on her to have a working lifetime of 20 to 30 years with a minimum of fuss and maintenance... If I take good care of her and keep her in a hangar, the work I do now will show when she celebrates her 100th birthday.

That said, many choices in covering will not be driven by aesthetics or desire to look pretty, but rather by desire to have her be the best plane for getting out and exploring the world. We covered doubling fabric on the bottom of the elevators (where the tires are most likely to throw gravel), where to put six-inch tapes (sure, the manual says two, but everybody leans on the leading edge when pouring in fuel), where to put inspection rings (everywhere you might ever need them, whether or not you ever actually cut them out), where to put inspection panels (inspection rings will let one eyeball or one hand up inside, but not both at the same time), installing seaplane scoops over drain holes, how to keep mud daubers out of drain holes, how to repair dents in a leading edge, and how to repair moose-attacked fabric sufficient unto flying back to town for real repairs.

As to using poly-fiber vs. ceconite for the covering? One burn test later, I have absolutely no regret or second thoughts on my choice.

That was some of the best money I've ever spent for instruction, including all my semester-long classes in college.