I've gotten rather a few emails from folks who look here for the latest project news, not to the project page on Facebook. So I thought I'd better do an update. Here's the latest photos.
On or about 9 January 2011, I built a rudimentary MIG welding lathe for making the stainless steel pintles for my flaperon and elevator hinges. These simple slugs of steel require a bead of weld to prevent them from escaping from where they are potted into the surface.
I also finished off the design of the elevator automatic connecting drive and sent parts off to Brad for incorporation into his aircraft.
On or about 23 January, the weather was nice so I did some rock climbing with Alia in Yosemite. I also welded up a wheeled cart for rolling the flaperon molds around, and did some prototype parts for the horizontal stabilizer forward attach.
Earlier, I had my friend Harald Buettner down at Precomtec R&D send me a chunk of ASW-20 flaperon. My thinking is that since the ASW-20 has a bit more wing flex than I (but not much more), it would be of advantage to see how they accommodated wing flex in their flaperon design. So on or about 7 February, I deconstructed the ASW-20 flaperon section to see what was inside. It was an eye-opener indeed.
Two end-on views showing the heroics that the AS guys go to to make sure their trailing edge joint is tidy. By contrast, their leading edge is seriously old-school; a big slug of solid balsa topped with shmoo. Note also the fuzziness to the saw cut that liberated this section. Except for a thin glass veil ply, it is all Kevlar. The foam appears to be Rohacell, and is carefully scarfed out so that it goes to zero thickness right at the trailing edge.
Here I've sawn through the leading edge and separated the trailing edge by running a taping knife through it. The Kevlar/Rohacell sandwich is so tough that it didn't damage the sandwich. Of course, that is partly because Kevlar doesn't give much peel strength.
Here I've peeled off the Kevlar from both sides of the foam so that I can weigh it and get the fabric specs.
On 12 and 13 February, I dragged Alia up to the shop and we prepped flaperon molds for the next round with wax and some other elements. Per tradition, I also made Brigitta a Valentine's Day token. This year the medium was MIG welded 1/8" cold-rolled SAE 4130 Chrome-moly steel.
You can also track the project on Facebook.
Homebuilt aviation is not for folks who don't try things at home.
page updated 19 February 2011 all text and graphics copyright (c) 2010 HP Aircraft,
LLC