Today I attempted to remove the vixen file tool marks from the edges on the rear spar reinforcement bars. I tried to keep the edge profile called for by the plans, but I ended up rounding all the edges. The plans say you can round an edge if needed so that the bars will fit properly against the rear spar. But that's only one edge, not all four. Out of an abundance of caution I reached out to Vans to confirm that I didn't mess anything up by rounding the edges and they told me the edges looked good and there is no concern about removing too much material. I began putting the satin finish on the rear spar reinforcement bars. I started with a maroon scotch brite pad, but I wasn't getting anywhere. Then I tried 400 grit sandpaper, which worked a little better, but was still taking forever to get out the deeper scratches in the metal. So I went down to 220 grit and that worked better, but was still taking forever by hand. So I ended up using my random orbital sander with 220 grit sandpaper, which made things easier, but I didn't have enough time to finish getting all the scratches out today.