Tail Fairing (3)

3 hours

The tail area is getting pretty close to complete, but one of the big items remaining was this fairing.  This is a piece that just covers the area between the two stabilators.

I started by laying out the flat pattern per the plans and cutting it out.

Since this part is not structural, I did what a lot of builders do and annealed the sheet metal to make it much easier to form into shape.  The technique that seems to work for this is to draw all over one side with a sharpie, then heat the metal from the other side with a torch until the sharpie disappears.

Once it cooled down, it was indeed very easy to bend.  It's kind of like a thick beer can.  Anyway, I bent the flanges first, using the edge of my workbench as a straightedge.  I could easily bend the flange down with nothing but my hands, and then I used a rubber hammer to pound it nice and flat.

Next I applied the curve.  The bottom of a 5-gallon bucket was about the right size to form the big end, and an aerosol spray can was the right size for the small end.  The area in between just kind of worked out once I got each end curved.

The part turned out pretty nice, but unfortunately it was just a bit too wide to mate up with the aft end of my turtledeck.

The part was easy to make, so rather than mangle this one trying to force it to fit I just started over.  This time I made a quick template out of a strip of cardstock to figure out how wide the big end should be.  I came up with 270mm, which is about 12mm narrower than the first part.

I made a new fairing, which went much faster then the first one, and the fit ended up much better.  I still need to figure out fasteners to attach the fairing.  The plans just call for sheet metal screws, but I think I will use small nutplates at least on the forward end where the fairing fits under the turtledeck.  I want to be able to tighten the screws there decently tight to hold the fairing inside that curve, and the annealed metal is so soft I think sheet metal screws would just strip out pretty easily.  So I'll come back to that.