Building the Legal Eagle Fuselage
Page Two

4/5/2010; fuse construction continues

A Harbor Freight right-angle clamp worked nicely to get the firewall station started. The tubing was mitered with the radial arm saw and two corners tacked.

Also shown in the photo is the flip-up #5 welding shield that clamps to a standard safety hard hat. This is the ideal rig for those of us who wear progressive lenses or bifocals. The traditional goggles won't allow us to look through the bottom portion of our lenses. The shield also stops the occasional weld splatter.

The firewall was clamped to the table, blocks added to insure squareness, and the last side tacked. Since engine details have not yet been finalized, the engine mount carriers will not be added at this time.

The major cabin tubing has been added and station one is jigged and ready for the longerons. Forward cabanes are single pieces of tubing.

The scale of the fuse is now apparent. So far the minimal jigging has worked very well at keeping everything straight and square.

4/6/2010; All major tubes have been added to the fuse. Still need to add seat bottom tube braces.

4/8/2010; Major fuse tubes are now completely assembled and tacked

I'm now getting my welding skills and confidence to the point where I'm comfortable welding the fuse. Several coupons have been welded from 4130 cutoffs and destroyed in various ways in order to insure a structural weld. The weld integrity is good, but still working on getting the welds to look nice enough to give me a warm fuzzy feeling. The plan is to do as much welding as possible with the fuse jigged on the table, then remove it from the table, invert it on saw horses, then finish welding.

I've settled on ER70-S6 filler rods and a #1 tip on the Mecco Midget torch.

About thirty-five hours (six good work sessions) went into getting the fuse to this point. Once the knack of cutting the fishmouths is acquired, the structure comes together pretty quickly.

So far.........no wind chimes have been made...........very little scrap tubing is in the shop.....

4/11/2010; fuse removed from jig and ready for welding

The fuse is now off the building table/jig and has been mounted on an engine stand. The stand allows the fuse to be rotated in 45 degree increments so it will be easier to comfortably weld the clusters.

Here is detail of how station one is attached to the stand.

Now........gotta figure out how to advance from gorilla welds to work I won't be ashamed of showing.

(gorilla weld [n]: a weld that is structurally strong but too ugly to claim)

4/16/2010; test fit vertical stab

The vert stab was placed on the fuse so the location of the attach fittings could be verified. The curves of the tail pieces line up nicely with the fuse and the hinges fall in the correct places.

Welding 101 continues on the rear half of the fuse. It is slowly getting better.................gorilla welds are now evolving to the level of orangutans...........

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I decided to forego making the strut/gear fittings and purchase a set of laser-cut fittings from John Bolding. The fittings are nicely cut and finished and saving considerable time in fabricating the eight fittings.

5/15/2010; strut/gear fittings tacked to fuse

The fittings were mocked up using 7/8" long pieces of tubing and 1/4" bolts. The fuse was carefully leveled and the final alignment of the fittings was checked with a level. They were trimmed and bent as necessary and tacked with the MIG.

5/27/2010;  wing attach fittings

Because the wing ribs have already been built and spar spacing is consequently established, a jig was assembled which consists of a rib, a set of wing spar fittings (unfinished) and the wing/fuse fittings. A length of 1/4" all-thread holds the fittings at the proper spacing to fit the rib and insures good alignment.

1/2" was added to the height of the fittings so the bottom of the wing would be even with the longeron. It seems I will be running pretty close on headroom and the extra space may be helpful.

6/1/2010; fuse primed

The welds on the fuse were cleaned up a wire brush in the air drill, then the entire fuse was gone over with maroon ScotchBrite pads followed by a lacquer thinner wipedown.

A pint of Valspar Tractor and Implement sandable primer was enough to put a light coat of primer on the fuse, gear, and assorted pieces. The primer was thinned with naphtha and shot with a small detail gun.

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