Well, it's January of 2015, and I'm finally starting work on my new stunter for 2014. After much backing and forthing (I owe Bob Hunt at least one totally trouble free purchase of a set of wing cores), and a long hiatus first to build some equipment for Howard Rush's trip to the Worlds, and then to catch up on my work, I'm building a Legacy from a Brodak kit.
The kit came to me from Don Curry, then president of the NW Fireballs. He had been given the kit by someone who got it from who knows where, and he gave it to me because he had no use for it. Somewhere along the line someone got the wing halves built and bollixed it up so badly that it needs a new wing. The thing's a horror. My flying buddy suggested that I string it up on a jig and sheet it, but the spar and leading edge aren't even fully seated in the notches everywhere -- there are spots where there's 3/32" of air between the notch bottom and the spar. So that wing is going onto the campfire at the flying field sometime soon.
I sorta semi remembered that Brodak sold wing kits, so I emailed them and asked. It turns out that while they don't catalog wing kits, if you ask nicely they'll make one for you. It also turns out that you need to be careful what you ask for -- had I asked for a Vector-not-40 wing kit, I would have gotten the right thing the first time. Imagine my disappointment when I finally got my bench cleaned off, a new building board (2' x 8' x 3/4" melamine) laid down, and started building only to find that I had the wrong kit.
Brodak is full of extremely nice, helpful folks who will fix their errors, even if you just want to keep what they shipped you by mistake and buy a rib kit for the right wing. They'll be getting more of my business, for sure.
I bought a set of 60" x 8mm carbon fiber rods from a kite shop to use for my wing jig. This will allow me to build the wing all in one piece if I want. I also got some shorter rods so I can build two halves. This wing is going to be jig built, and it's going to be as straight as I can make it.
While I'm waiting for the correct box of goodies to arrive from Brodak, I decided that I'm going to make this kit with a molded leading edge, and that I'm going to make the buck for it. This should be an adventure, because I've never cut foam for real. Hopefully I won't waste much time on this -- if I do, I may back out of the molded LE decision and just make it the old fashioned way.
Since I'm doing the cutting in an off-the-cuff what-the-heck sort of way, I just bought a chunk of foam from Home Depot. Unfortunately, Home Depot (at least around here) doesn't sell foam thicker than 2". So tonight's work was to make a 4" thick blank using two layers of 2" thick foam.
I'm starting from near-scratch here. I made a bow from a 5/8" dowel, some 1x2, finish nails, and some used .015" flying lines. What you see in the picture has about 29" between the bow arms, which is just about exactly what I need to do the job.
I'm using a 12V power supply that I use for charging batteries. It seems to hold the wire at a decent temperature -- at least, it's not getting hugely hot, and it does cut the foam nicely if I'm patient. My 30 inches of wire pulls about one amp from the supply. I have no clue if it's too hot, too cold or just right -- but I'm confident that with care I can cut a buck that'll be good enough to mold leading edges on.
I made a test cut, freehand with the bow and some scrap foam -- it seemed to come out OK.
My flying buddy had, until today, infinitely more experience cutting foam than me -- he has a friend who cuts foam and chats. I knew from Tom that you want to make tick marks on your cut, and count them out as they go by. After one cut that happened too fast, my assistant suggested that I make the tick marks spaced closer together, and please count them out as eight notes, in 4/4 time (he's a musician. that makes perfect sense if you're a musician).
The final picture is my blanks glued together into one master blank. I'm gluing with epoxy (I don't know what else will cure nicely inside of foam), being careful not to leave any epoxy anywhere that I'll want to cut later. I'm using my favorite relativistic clamping system, that uses the very curvature of space-time itself to induce force on the items being clamped.
Tomorrow I'll cut the buck and either joyously start molding leading edges, or cursing myself for screwing things up somehow.