HP-24 Project

Update 22 September 2003: Both sides now

Doug Gray and I did manage to get the other side of the aft fuselage plug skinned on Wednesday last week. We encountered no particular problems. On Thursday I unbagged it and attached the vertical pipe that attaches the vertical fin portion of the plug.

The fuselage skins came out with a lot less orange-peel than we saw on the vertical fin. The .014" mylar seems to be doing its job a lot better than the thinner and less stiff .005" material. It's not a perfect surface by any means, but it sure won't take much sanding to finish out.

To align the vertical fin, I bought one of those smart levels that reads out to .1 degrees. I'll use that to set the fin's zero incidence. I played around with the alignment some on Thursday, and I think I know how it'll make it work.

This morning, I brought a pound of microballoons down from the shop to use in making the fillet between the fin and the fuselage. I'll use it to extend the ruled surface of the fin to where it intersects the surface of the fuselage cone. Then I'll fill in the intersection a little bit, and sand the intersection fillet to whatever radius I get by wrapping sandpaper around a 2-liter soda bottle. That'll be one of the first applications of a metric tool on this project...

Actually, there's one other thing that wants for doing this week - I have to sand down the scarf joint between the right and left aft fuselage skins. This is the same job as I've so far done for the leading edges of the horizontal and vertical stabilizers. But the larger radius of the fuselage means that there's more material to sand away. I got a head start on this job by whittling away a lot of the overlap using a pocket knife while the epoxy was 1-day cured, but there's still a lot of material to remove.

This week, the elevator plug cores should arrive; if so we'll get a head start on them. This elevator plug incorporates a lot more camber than the equivalent portion of the horizontal stabiliser plug we already made, and also has the hinge and seal radii already incorporated.

Up at the shop this weekend, I prefabricated a bunch of truss parts for the table where I'll build the wing plugs. The wing table needs to be straight and square, and needs to be adjustable so I can remove any twist that tries to sneak in. I recycled the engineered joists from the spar plug table, and I'm adding legs and truss members to make them stiffer.

This weekend I also added wheels (two fixed, one castoring) to the wing spar mold. That's so that when I install the wing table in the shop I can roll the spar mold under the table and save a bunch of floor space. When developing 18-meter ships in a 20'x30' shop, every square foot counts.

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page updated 22 September 2003 all text and graphics copyright (c) 2003 HP Aircraft, LLC