Flap leading edge fab

What is the best way to prefab the leading edge skins on experimental flaps?

buy them.... univair sells blanks

or you could do it in a sheet metal break, little by little...

Dakota Cub!
John

Fasten two 2x4s to a piece of plywood with the appropriate spacing. Place the flat aluminum on top with the bend centerline in the center of the gap. Then force a piece of plastic pipe of the appropriate size on top of the aluminum down into the slot. Allow for spring back.

The original leading edges are 3003 aluminum and very soft and easy to form. The originals where broken on the leading edge with a roll on the top surface. I have always bought the blanks from Univair, would consider Dakota as well. Not sure but believe they use a better alloy like they do on the spar. I think Pete's way would work well. I have a press break and would use it with the proper radius die, clecoe the bottom and then pull the top around the ribs to form the curve and drill. I made some fixtures to hold the skins while riveting the ribs in. I will get a picture, they were pretty helpful.

Here is the fixture I made out of MDF years ago to hold the skins while drilling and riveting the ribs inside.


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This is what I wound up doing.
I slide the correct material between the plywood sheets of my work bench. I then screwed the plywood sheets together to clamp the material securely. I then drilled an aluminum rod of the correct radius for screws and countersunk the holes every 6 inches. I then screwed the rod to the edge of the bench on top of the aluminum sheet. I then clamped boards to the free end of the sheet aluminum which was .025 2024. Then with considerable effort I folded the aluminum around the captive rod clamping it to the table. It took a little persuasion with a mallet on the boards. I did a secondary bend with another rod placed on top of the workbench. The results turned out nice.