Chop Chop

Paul Straney working his magic.

This glider project began with the fuselage from a motorized airplane.  There are a few mods needed to make it fit for the glider version.  One modification requires removing the circular pipe (it looked like a veritable Hula Hoop) that was welded to the very front of the fuse and held the front edge of the fabric such that it blended into the engine.  Since there is not engine on the glider, there is no need for the Hula Hoop.  Paul cut it off, and then filed the excess metal down to make a nice smooth surface where it had been welded.  The lesson here is make sure you leave a little bit when cutting away the excess.  That way you can file it down slowly and it will look like it never had an appendage, and it will be strong because there are no nicks in the remaining metal.  Having seen Paul's handiwork, I can say that once a coat of paint is put on the fuse, you will never know it had a Hula Hoop.

Digital French Curve circa 1945

Dick Weger sorting hardware

First, I wanted to show you Dick Weger as he charges ahead with his new task.  A shipment of hardware came in and Dick decided to sort it so the parts could be accessed quickly.  Yes, a minute saved when looking for a part is important when you have so many parts to assemble.  Let's see, if sorting saves a minute per part, and the airplane has a gazzilion parts, then Dick saved us a gazillion minutes, which divided by sixty minutes in an hour, is a boatload of hours.  Thanks Dick.

Speaking of gazillions, I was talking to Dick about his early days at Martins.  He told me about how they had to prototype 12 foot wing ribs, but did not have the die to make them.   So, they made them one at a time on a fancy thingy called a numerical controlled milling machine.  Think about this, this was around 1945, so how did they do it?  Dick said they had paper tape systems back then, and he had to punch the data into the paper tape.  Hmm, lets think about this.  The airfoil curve would have probably a gazillion data points that needed to be entered, well actually two times a gazillion (upper and lower surfaces) equals two gazillion data points.  But, Dick said they didn't have to enter that much data because they could program the paper tape with a series of curves: AKA start here, end here, use this radius, repeat.  Hence, the concept of a digital french curve.  So cool.  This is the same algorithm I use when drawing curves in my CAD system.  Same principal, but silicon chips instead of punched paper.  Thank you Dick for the interesting slice of history.

BTW, if the digital french curve reduced the data points entered by a factor of ten (just guessing), then Dick would have only entered two-gazillion divided by ten . . . wonder what that equals?