Section 14 – Top Skins

I finished up dimpling the top skins today and got the rivet lines primed. I cut a slot in a scrap piece of cardboard to paint the rivet lines in the skin and make it look at least a little bit better than free hand.
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I also primed the wing walk doublers on both sides
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Section 14 – Top Skin

Yesterday I continued working on the inboard and outboard top skins for the left wing. I removed a small amount of material from about 1″ of the forward corner of the inboard and outboard skins where they overlap to help them lay flat. Then after complete deburring, it’s time to dimple.
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I got the top inboard skin dimpled. For the most part, I used the Cleveland spring-back dimple dies in the DRDT-2 but on the holes along the forward edge, I used the smaller Avery die so it wouldn’t flatten the slight bend.

I also added a new fixture to the workshop.
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I built the DRDT-2 table expecting to use it in conjunction with the main workbenches. But of course, they are occupied holding the wing so I need something to support skins while dimpling. I purchased a bench grinder stand from Harbor Freight and added castors. I think it was $40. I then attached a piece of the 3/8 plywood (shipping crate top) and carpet and it is a handy movable surface for supporting the skins. I couldn’t have built anything any cheaper and this will also be useful holding the grinder or band saw.

Section 14 – Wing Walk

No pictures today (because I forgot to take them) but a quick note to say that I finished countersinking the inboard top skin / wing walk doublers. This section of the skin is countersunk because there's two layers of .032 aluminum making it a little thick for dimples. The rest of the top inboard and outboard skins are dimpled and that's the next task.

 

Section 12 – Dimpling the Ribs

Finished up deburring the 40 sized holes on the upper and lower flanges of the wing ribs today. After deburring all of the holes, each one was dimpled. I couldn’t use the DRDT-2 for the dimpling of the ribs so I used the hand squeezer. I mounted it to the workbench so I could hold the rib with one hand and dimple with the other.
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So for each of 28 ribs, I have now:

  1. deburred the edges
  2. fluted the flanges to straighten the rib
  3. final drilled the holes in the flange (around 45 per rib)
  4. deburred the hole
  5. dimpled the hole

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