Section 8 - Horizontal Stabilizer (countersinking/dimpling; substructure)

Lots of progress the last couple of days - these myriad parts are starting to look like a horizontal stabilizer ... well, the skeleton anyway.  Much of the work has been deburring edges and holes ... a thankless but necessary task that took a half dozen hours.  Not shown, dimpling the ribs and skins, a task I very much enjoy (using the DRDT-2 is therapeutic). Below are a few pics from this midpoint stage in assembling the H.S.

Countersinking a couple hundred holes on each side of the front and rear spars, and stringers (rear spare shown here). Aluminum shavings/filings everywhere!

Section 8 - Horizontal Stabilizer (initial work, front and rear spars)

Starting with the Horizontal Stabilizer, I am priming ONLY non-alclad parts, since the pure aluminum coating on the alclad parts acts to prevent corrosion.  I estimate that this will save about 10lbs in weight overall, as compared with priming all non-skin internal parts, which was my original modus operandi.

Rear spar with 4 of 5 brackets clecoed (this is the only pic I currently have of the rear-spar - it is currently riveted and sitting awaiting assembly with the ribs, stringers, etc.):

Section 7 - Rudder (riveting everything together)

Lots accomplished today, much of which was riveting.  This post will be mostly pictures, with only a few words, since I'm pooped from almost 8 hrs in the workshop.  All the parts preparation the last week or so made today just knocking out the riveting tasks one-by-one.

Back-riveted stiffeners to rudder skins and and blind-riveted stiffener clips to right rudder stiffeners:

Section 7 - Rudder (new bench/shelf; trailing edge; priming)

I needed a little more storage for the large flat and odd-shaped  pieces in the empennage kit (the floor wasn't working), so a fellow builder (Ken B.) recommended 2x4basics (Amazon) to create a 4'x8' bench/shelf.  He uses this setup for the wings (large) in lieu of the EAA workbenches.  I'm using it for storage, at least for now - thanks for the suggestion, Ken.

Section 7 - Rudder (trimming; initial assembly; drilling trailing wedge)

The rudder is making the vertical stabilizer seem like child's play.  Lots of little parts that all need to be separated and trimmed down to their final shapes.  Skins are VERY thin (0.016") and feel like they will bend/break when I move them around.  Tons of rivets in the skin as well as lots of LP4-3 (and other) blind rivets to zip the entire assembly together.  Amazing engineering though; I like the lead weight used as a counter balance.  For those of you, whom have flown an RV, that smooth feel of the control surfaces is due in large part to well-matched counterweights.

A few pictures from this part of the build are below.

Section 6 - Vertical Stabilizer (finished! ... well, almost)

Over the last couple of days, I plowed through riveting the doublers and hinges to the spars, the ribs to the front spar, the skin to the assembly, and the rear spar to the final assembly.  I had to drill out a few bad rivets, but otherwise, it was fairly straightforward.  BUT, there is ONE darn rivet that even my thin tungsten bucking bar, on its side, can't buck (FYI, it's the forward-most rivet where the skin attaches to the top spar). I guess I'll be putting in an order for a thin yoke with Cleaveland Aircraft Tool!

Aside from that one rivet, the rest of Section 6 is complete.  In total, it took 31.1 hrs to complete a whopping 5 pages ... and that doesn't count most of the reading, planning, and cogitation!  This must be a slow-poke record.  Well, I'm taking my time.  Here are a few pics as I riveted everything together:

The pneumatic squeezer, with adjustable set to rivet, made quick work of the AN470AD4-sized rivets ... now, I just wish it was that easy to use the squeezer on the skin-to-spar AN426 rivets!

Section 6 - Vertical Stabilizer (priming)

I'm now at the stage of cleaning/prepping and PRIMING the metal - a topic that has been the subject of many highly opinionated forum posts.  It seems there are as many ways to prep and prime as there are people who have completed RVs.  From reading WAY too many of those posts, I'll summarize what I feel to be the best balance of quality, durability, weight, cost, ease and efficiency.

After all metalwork has been accomplished, including dimpling and countersinking (but, of course, BEFORE riveting anything), I cleaned the surface of all pieces to be primed with 100% acetone, using blue nitrile gloves to prevent oils from my skin to contact the surface and prevent the primer from sticking.  I decided to prime the following: all 4 ribs, both spars, the two doublers, and the internal rivet lines in the skin (not the outside, and NOT the entire internal surface skin - it already has a nice protection from the pure-aluminum alclad coating). I am NOT priming the 6 steel hinge brackets, since they came from Van's powdercoated (but, after match- and final-drilling, I did add a little 3-in-1 protective oil to any exposed steel surface, to prevent rust).

After acetone cleaning the surface, I used a Scotchbrite maroon pad to scuff any surface to be primed - for the ribs, spars, and doublers, I scuffed every surface. For the skins, I scuffed only the internal rivet lines. I then cleaned the surfaces well with Kleenstrip Prep-ALL, let dry, and primed with SEM #39683 self-etching gray primer (aerosol can) - it is expensive (about $21 per 15.5oz. can), but it is easy to apply (no HVLP gun needed!), dries quickly, and is tough after it has cured.  I bought a little spray can trigger handle to ease application of the primer, and primed until I couldn't see metal (~3 light passes or so), waited 5 minutes, flipped the pieces and primed the other side (the skin was primed standing vertically). I plan on letting the primer cure at least 2 days before riveting.  Here are most of the pieces, drying/curing after priming the second side: