Thursday morning 30 October. Once more, I'm not invited to Grace Slick's birthday party, so I use a vacation day to work at the shop. When I get there, Brad is liberating his finished horizontal stabilizer from the molds.
The stabilizer weighs in at 8.8 lbs, about half a pound lighter than the one I made a few weeks back. I think most of that weight savings is in not having gelcoat.
Brad and eight feet of carbony goodness. Brad's obviously a bit taller than Bruce Carmichael.
Moving forward, the guys start cutting core foam for Brad's lower wing skins.
Meanwhile I start welding up a carbon rack to make it easier to apply the +/-45 swaths of carbon cloth. Most of the content of this device is the product of dumpster diving. The 3-wheel carriage was left by the previous tenant, and the orange and black tubes came from a leaking engine hoist that my landlord threw away.
Doug bevels the edges of the core foam.
This is the much-abused bottom edge of the pail of epoxy resin we got from Rhino Linings, which is where you now get the epoxy resins that used to be sold by Jeffco.
The bias roll rack and the pre-cut veil cloth.
On 31 October (happy Halloween!) after a morning spent prepping the lower left wing mold, Brad pulls carbon onto the wetted veil cloth.
Doug positions the core foam while Brigitta mixes the next pot of resin.
With all of the carbon in place, the peel ply, perf ply, and breather laid down, Brad and Brigitta lay on the vacuum bag membrane.
Bagged down and vacuumed.
Doug trims the horizontal stabilizer cove where the elevator fits.
My project for the week was molding the jettison hood at the forward end of the canopy frame. After assembling a bunch of prisms of PVC foam and glassing them, I smear on a bunch of bondo and rough-sand it as you see here. After this I brushed on a cabocil-thickened coat of sanding primer, sanded that to shape, and then applied and sanded four coats of rattle-can jalopy primer.
The trimmed stabilizer with the forward attachment bolted on and the aft fitting (which bolts to the fin spar) applied. The elevator skin looks rough because you're looking at the inner surface of the upper skin.
The next morning the low clouds overhead took on a strange roiled appearance.
Here's Brad's lower left wing skin, freshly unbagged but with the other consumables still in place.
After peeling off everything but the peel ply, which we left in place to protect the carbon surface, we roll the mold into the storage bay. Here I rig my hoist to the upper left wing mold.
We traverse the upper left over the lower left...
...And execute a rollover maneuver...
...And lower the upper mold onto the lower. After that, we raise the upper right, roll it over, and place it on top of the upper left. That frees the lower right to roll into the work bay.
And after a lot of waxing and prep and layupping, the lower right wing skin is bagged down and the guys are cleaning up and moving to the next project.
Here I use a heat lamp to cure the last coat of primer on the jettison hood plug.
And then apply some radius fillets with modeling clay and a coat of PVA mold release.
We brush on the tooling coat and then slather on several layers of fiberglass.
Our much-depleted list of things to do. The only thing we didn't get to was cutting metal bits for the welder to assemble into landing gear parts.
Now the lower right wing skin is unbagged, and we've moved the upper right mold in so we can mark out the airbrake locations.
Left to right, Bob Kuykendall (me), Doug Gray, Brad Hill, and Brigitta Kuykendall. One of America's foremost sailplane development teams at the end of another fruitful Akaflieg Douglas Flat.
Homebuilt aviation is not for folks who don't try things at home.
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page updated 3 November 2008 all text and graphics copyright (c) 2008 HP Aircraft,
page updated 3 November 2008 all text and graphics copyright (c) 2008 HP Aircraft, LLC