As I wait out the colder weather so I can prime parts and rivet, I sneak ahead and prepare the next bolus of parts for priming. To that end, section 26 is a 22 page beast, filled with a multitude of parts big and small, each with various steps towards being ready for riveting.
One thing to keep in mind is that the #40 holes in the bottom flanges of all the ribs must be dimpled to accept the center bottom skin. In most cases, that is not stated in the plans. If you're uncertain, skip ahead to see where the skin is dimpled and where it meets the ribs to convince yourself.
The F-01415-L/R outboard seat ribs must be fluted to conform to the curvature profile of the skin. Step 1 on 26-06 describes the process required to morph a straight rib into a properly curved one. It's a protracted series of repetitive steps: Flute, cleco until there is resistance, un-cleco, re/de/new-flute, etc. Here's what it looks like with the lower flange properly fluted. The upper flange is then matched to the lower.
The F-01443 center section lower doublers must be countersunk for an AD4 dimpled 0.025" skin. These doublers are about as thick as an AN426AD4 head so the plans require the doublers to be cleco'd to each other to provide more material to keep the pilot from elongating the holes. When you get one side countersunk and switch to the other, elongation is essentially incipient. Go slow. One might consider just buying another F-01443 part from Van's for the sole purpose of providing more thickness.
The F-01448B gear brace bars are quite thick. As such, following manufacture, they come out rather warped (thankfully, in only one dimension). Left: One out-of-the-box and another after straightening. Middle: After straightening both. Right: The method I used to straighten (originally described here).
Once straightened, the entire gear brace assembly can be cleco'd together and final-drilled (note, you'll need a 1/8" cobalt bit to complete this step, which is inconveniently sized between a #30 and #31).
At first (and second, and third) glance, the F-01484 center bottom skin looks symmetrical. And it is, but in shape only. There are exactly 8 unique holes that are right of centerline. Below, I've circled the right-side-only holes which will later accommodate the comm antenna (the other 5 are non-dimpled drain holes as described in Figure 1 on 26-11 ), thus the image shows the skin from the top (that is to say the side for your butt and feet). A recent thread on VAF discusses the subtle asymmetry of the skin.
After a concentrated hour deburring the myriad of holes in that skin, my hands howled weary and weak with soreness. With such strong protestation in...uh..."hand"...thus ended the weekend's work in favor of several days of healing.
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