When I left off last week, I had dimpled the #8 screw holes and hadn’t yet started in on the 3/32″ skin holes. There are a lot of them! Because of the way the tank skin is bent, I needed to do some work getting my DRDT-2 set up. In New York, I had a nice bench with an overhang set up permanently against the garage wall. For most work here in Texas, I can get away with bolting my dimpler to one of the EAA work tables. For the leading edge and tank skins, I need a bit of an overhang. I thought of a bunch of possible ways to set this up. In the end, I did something very simple and effective. I used some 3.5″ x 5/16″ lag screws and a piece of 2×6. This very solidly tied the extension into the table. A couple of 1″ lag screws holds the dimpler to the 2×6. It worked very well.
So I sat in the comfy chair and twirled a dull drill bit in the holes. I like this method. It is very fast and easy to control. It just barely takes off the burr while leaving the hole nice and smooth.
I had high hopes of getting in some practice touch and goes, but all thoughts of that were quickly dashed. It really poured! Even when the airport was in the clear, there were nasty thunderstorms lurking all around all day long.
The DRDT-2 and the carpet covered boxes worked vey nicely. The dimpling went quickly, but there were still SOOOO many of them! I finally got all of them done…
Next, I worked on the fuel caps. There’s a pretty red anodized base and a cheap looking plastic sealing cap. I can get replacement ones made out of machined aluminum, but at $145, it is pretty pricy. I don’t like the idea of painting the plastic though. Will likely defer until it is time to paint the plane. There are some steps, that I’m really excited to get to. One of them is this shot of the fuel cap base clecoed in. Pro-seal time is close at hand!
One clever hint I saw is to set up a swiveling base for the stands. The Pro-seal is messy and hard to work with on a good day. These swivels will let me rotate the tank so that I have a good (better?) angle for both applying the sealant and for riveting. Not quite done in this picture. I cut these pieces from the end of the 2×6 I used to support the DRDT-2. Added a rounded edge and then drilled them out for a 5/16″ hex bolt for the axle. We’ll see how they work soon enough.
Next time, I have a few non-Pro-seal tasks to finish on the tank attach brackets and shims. Standard trim, deburr, prime (just the external parts), and rivet. If I get really saucy, I’ll do the nut plates on the inboard rib (screws pull in the fuel lever sender. No gasket, only more tank sealant). If I’m super productive, I’ll do the first set of sealant tasks (closing the tooling holes and adding the fuel flanges and anti-rotation plate).