Introframe

Update: 2007-03-04

Sonex 815, both wings done. 3/4/07

(See Sonex 815)

A few things about some builder tips floating around:

1. Using a big press to bend the leading edge should be abandoned. The vacuum-form method is quicker (no press to build), easier (no heavy parts to lift/move/secure), reliable (no wrinkled skins as an insufficiently stiff press flexes), and cheap (return the pipe when you're done, and the cost is about 1 roll of masking tape per skin, or about $1/skin in 2007). Also no large forces either trying to bend the press up out of the floor, down into the work table, or bend the pressing beam up out of the press. Vacuum-forming applies a lot of force, but it's with a tiny pressure difference over a large area. There is no bending load on the pipe or work table that the pipe is secured to.

2. The "construction tip" floating around about drilling hinges with the 2nd side attached to the side being drilled with the hinge open to about 90 degrees does not do what it claims. The problem is the hinge needs to be stiffer IN THE PLANE of the hinge, not in the up/down direction (parallel to the drill axis). In the drill axis direction, stiffness can be obtained simply by clamping it to the item it is being drilled to. But these things are flimsy enough, even in the direction where the material is 1/2" wide that the hinge can end up not drilled straight. The ONLY cure for this is a good set up - meaning your wing aft spar trailing edge is straight, and the hinge is clamped to it at a consistent distance of overhang. A good way to do this is to use a depth measuring gauge at each hinge lug. Having the 2nd piece of hinge in place will stiffen it in the plane of the hole drilling axis, but that doesn't really matter.

Now it might help if the hinge is attached to the 2nd side and opened out flat to 180 degrees. That way you're doubling the width in the direction that needs more stiffness.

Thanks for letting me get that out. There's so much information floating around that without having tried it that it's hard to tell if it's for real.

Sure, the press has bent a lot of skins. But I saw a Sonex this week with those press-bent skins. There are scratches in the leading edge where the edges of the press apply pressure. My vacuum-bent skins have no such marks.

Update: 2006-12-29

Got the site re-hosted so I can now make changes after the previous host was sold, my password lost in the process, and their new owner being completely unresponsive.

Update: 2006-01-21

A tiny bit of info on the S/N 815 build is here on the 815-1 and 815-2 from the menu on the left side of the page. This has been superseded by a separate site via Kitlog which is a lot quicker than writing this site.

-Link to Sonex 815 Build Website

Update: 2005-05-12

Plans no. 815 arrives 4/29/05.

What happened between Sonex 42 and 815? Motorcycle and Miata2, among other things. After about 5 years away, I had to give it another try.

Left wing ribs drilled. 6/7/00

(See Sonex Wing3)

Fuselage well underway. 12/26/99

(See Sonex Fuse-fwd6)

When the wild ducks or the wild geese migrate in their season, a strange tide rises in the territories over which they sweep. As if magnetized by the great triangular flight, the barnyard fowl leap a foot or two into the air and try to fly. The call of the wild strikes them with the force of a harpoon and a vestige of savagery quickens their blood. All the ducks on the farm are transformed for an instant into migrant birds, and into those hard little heads, till now filled with humble images of pools and worms and barnyards, there swims a sense of continental expanse, of the breadth of seas and the salt taste of the ocean wind. The duck totters to right and left in its wire enclosure, gripped by a sudden passion to perform the impossible and a sudden love whose object is a mystery.

Wind, Sand and Stars -Antoine De Saint-Exupery