Laying out the Tail

Once the tubing arrived, I had the jig table built, and we finally cleared off the garage sale remnants, it was time to lay out the tail surfaces.

Horizontal stabilizer leading edge

The dimensions on the plans were marked out on the table and centerlines were drawn in. Then I could offset that centerline to mark out where edges of the tubing should land. Jig blocks can then be screwed down touching that edge line. I'll skip a lot of the specifics because it's hard to visualize without pictures and I took very few pictures. Each tail surface is made up of a tubing perimeter and C-shaped sheet metal ribs. The ribs were bent up out of sheet steel with a borrowed bending brake.

Bending tool

The trickiest part of these surfaces was bending the leading edges around the 5-1/2" curves called out on the plans. The radius is tight enough that I could not bend the tubing without kinking, even when packed tightly with sand. I decided to try building a sort-of mandrel bender. The device I came up with has a bending die on a long handle that cradles the tubing and forces it around a round jig block. It took a couple sample pieces to get the hang of it and dial-in the bender, but the bends turned out well enough.

Vertical stabilizer and rudder laid out

Once everything was laid out, I could tack-weld it all together and pull it all out of the jigs.

Comments

10 months in under 10 minutes.

I don't feel like going into depth on every little aspect of work I've done over the last 10 months, so I'll hit the highlights and if anyone has questions, feel free to comment and I'll elaborate. As the year started the garage was cold. With a propane heater it would get warm enough to work for a few hours, but because 4130 steel is an air-tempered alloy, it needs to be sufficiently warm out for welding. Long story short; I can't weld, so I make parts. I plugged away making little bits so I can use them when it comes time to build a new assembly. The landing gear legs and spring struts have metal straps to reinforce the bushings in the ends. I knocked these out in a couple days after work. Likewise, the tabs that will become door hinges and the fittings for the tailwheel were cut, drilled, and deburred. As it warmed up and I got an order of laser-cut parts the aileron control arm and pulley brackets were welded to the torque tube for the control stick. I also cu...

Gear Legs

Last updated November 8th, 2022!? Time sure gets away from you sometimes, doesn't it. Woof.. A lot of time was spend figuring out main landing gear legs. The first step was taking the info from the Piper drawings and laying out the gear v's full size on my table, then jigging the parts in place. This is what we're building. The left side of the picture would be facing the front of the aircraft. And here's the jig laid out on my table. The nearer jig sets the relationship between the forward tube and the axle. The farther jig aligns the forward and rear tube as well as the bushings on which the gear leg will pivot. With the jigs laid out it's time to manufacture parts. First came the pivot bushings, and they were a bit of a process. First the little U-shaped piece of metal that holds the bushing needs to get bent to shape. I made a little die the right size to bend the material in my vice. After the U is bent it then gets a notch ground out to fit around the...

Drag wires

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