Shop: Rivet shaver bliss.

I bought a well-used rivet shaver off of eBay for $110 shipped.  It is a US Industrial/Aerospace Tools, model US 7337R3 with the guides.  The 'net didn't turn up any information on it.  Regardless, it works like a charm.  The much higher RPM afforded by this tool, compared to a 3000 RPM hand drill, coupled with the stabilizing guides, provides much happiness.

First, using some scrap angle, I set the cage to where the bit just shaved the surface.  Then I backed off the cage until the bit no longer shaved.  Running it over the proud rivets, it took them right down to flush in one shot.  The shaver loves air, so it made my compressor work hard.  Sometimes I had to hold off until the compressor caught back up.

Here are before and after shots of two different proud rivets.  You can see that the bit only shaved the rivet head, not the spar flange.  The scuffing on the right is just the primer ("spot-primed" the countersunk holes, per Section 13) removed from the flange.  Now that these rivets sit flush, I no longer need to worry about them gouging the top skins.