HP-24 Project

Update 8 November 2007: Makin' Flippy Flappy!

While I've been noodling around down here working on the horizontal tail and elevator, Brad and his friends up in Monroe WA have been working away making molds for the flaperons. What he's done is to take the rough hewn flaperon plugs that I cut away from the wing plugs and added the upper hinge radius to, smoothed them out, set them up with various dams, and made molds off of them.

One not-inconsequential part of that work is to straighten out the flaperon plugs, since they've acquired a substantial bow in the chordwise plane. It looks to me like the MDF that I used for the upper hinge radius has swelled since I put it on, stretching the leading edge of the parts and sweeping the ends back. Brad's done a good job of forcing them straight for molding, but the lesson is pretty clear: going forward, use more stable materials for such long limber plugs. High density tooling foam would have been a better choice.

The photos:

Brad and fellow Tyvek Warrior Chuck Anderson laying up a flaperon mold.

Two by two, hands of blue

On the left is the inboard right flaperon mold, upper and lower. On the right is the outboard right flaperon molds, separated. Each flaperon section is about 136" long. The color difference is because (at my insistence), Brad tried a different tooling coat than on different molds we've done in the past. The success of the experiment is debatable. My bad.

Orange, black. Just in time for post-Halloween candy sales!

Same molds, different end.

Mmmm. Chocolate...

The flaperon plugs, finished and polished for molding.


The inboard right flaperon mold, opened. The forward flange required some reworking.

Back to the TC1611 next time.

Homebuilt aviation is not for folks who don't try things at home.

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page updated 8 November 2007 all text and graphics copyright (c) 2007 HP Aircraft, LLC