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.

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Fittings. How fitting.

Not much has happened on the Ace this year. The winter was long and spring has been very cold, so I spent a long time waiting for the garage to warm up. Now that there's a little heat down there I've been making some headway on the next step of my wing build: fittings. I copied the parts off the plans into CAD and then printed them onto cardstock to use as patterns when laying fittings out on the steel stock. First I tackled the brackets that will hold the pulleys for the aileron cables. I have a lot of extra material in case I had to remake these. The next step was to bend up my fittings. There is one fitting that mounts to the forward side of the strut which gets bent to a 90° angle. The fitting which mounts to the aft side of the spar gets bent at about an 85° angle. I forget the exact number, but don't feel like looking it up at the moment. Next I cut out the aileron control horns. My Harbor Freight porta-band chucked into my vice works well for cutting thes

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

3-D and waiting.

On January 18th I posted my last blog update; both fuselage sides were tack welded. That was seven months ago now. I should update more regularly. Okay, self-flagellation over, let's get to the content! Once both fuselage sides were tack welded, I pulled all the jig blocks off the table, elected not to repaint again, and just laid out the stations for the top view of the fuselage. We lay out the top view because the top of the fuselage is flat which makes it a lot easier to jig things up if you lay out the fuselage upside-down. With the top view lofted out on the table I could start adding in jig blocks starting in the cockpit area where the sides are parallel. A stick and some clamps help hold the sides parallel for this photo op. Now may be a good time to mention, if I haven't already, that I am widening this fuselage from stock. The original Jr Ace (Model E) was 33-1/8" between tubing centerlines at the widest point. This makes for a pretty cramped space when two peopl

Aviation Coming Eventually

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