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Builder's notes:

• Note the holes drilled through each of the solid nose ribs. These come pre-drilled from the factory. Before attaching these to the aileron spar, stack them together so that the back edges of the pieces are flush. Check that the holes align well, because the tolerance is tight, given that you will have to run an aluminum tube (five feet worth) through all these holes, after the leading edge material closes the structure. If the holes do not align well, or are too tight for the aluminum tube to pass through fairly smoothly, take the time now to enlarge and match drill them. I found during the torque tube installation that a little graphite powder as used to lubricate locks will ease the progress of the tube.

• The geodetic pieces in the trailing edge bays actually rise a little bit above the eventual plane of the fabric covering. This is bad as it will guarantee abrasion of the underside of the fabric, no matter how smooth you sand the wood strips. I discovered this after covering the ailerons with fabric, unfortunately. I had to cut small holes in the fabric near the crossing of the geodetic strips and, with great patience, use rib-stitching cord and long rib-stitching needles to tie the top and bottom geodetics together at the crossover in order to pull one down and the other up and away from the fabric plane. Much like building a ship in a bottle, I suspect. Not very much fun. Tie these together before skinning the ailerons!

• The fabric patches easily, before it is painted, and I think the round patches with pinked edges give a little character to the aircraft even before it gets knocked around from use. However, treat the fabric gently. It is very tear resistant, but not so much to abrasion. Before it is painted, the material is vulnerable in handling - never slide a fabric covered piece across a surface - pick it up and place it, making sure the destination surface is clear of debris - splinters, grit, metal shavings, staples, nails, etc, etc. And since you will be sanding the fabric surface between undercoats and color coats, any less than smooth structural surfaces will cause pinholes, or worse, to appear in the fabric. Check every contact point in a final sweep just prior to covering the structures with fabric. Then later, while sanding, use light pressure when between fabric contact points, as there will be geodetic crosspieces beneath the fabric, which you may depress far enough to contact, and bingo, another pinhole!