Took it easy the last couple days-- went to a fly-in grill-out on Tuesday (this is like the third time in a row we drove to a "fly-in"... gotta change that soon!) and hung out with some chapter 33 folks and our friend Derek who has also started on the RV-10 build journey himself! Excited that there are so many RV'ers around the area, hoping to do everything I can to help spread the "disease"! :-) Anyway, other than deburring one F-1001G gusset with Derek to show him the joys of fuselage-building after getting back from the cookout, the firewall has pretty much sat dormant since Monday's session.
Tonight, though, we got back to it. No marathon build session, but we did complete deburring, countersinking, and dimpling all holes for the firewall assembly. It was pretty straightforward for 95% of all the holes, but I was a bit confused about what to do with the 16 holes at the very bottom of the firewall that don't have any parts attached to them. The plans don't really say anything about them specifically, other than it looks like there are rivet callouts for them in the next pages. I'm thinking they must be just dummy holes that will be plugged with 4-4 flush rivets. (EDIT 6/24/15: Leave these holes alone for now! They are not dummy holes, they are used to attach the fwd floor ribs. See GOTCHA entry in this post.) Otherwise, everything was pretty straightforward... just have to watch out for two of the fourteen nutplates that need to go on the other side of the firewall, which requires different dimpling/countersinking procedures.
By the end of tonight, I believe we have a fully prepped firewall section with the aluminum parts ready for primer and all other parts ready for assembly. Should make for quick work this weekend!