This week saw final riveting on the hinges, trailing edges, rib tips, and bending the leading edges.

A special modification to a standard bucking bar was made with a grinder and round file. The depression in the bucking bar face exactly matches the trim tab hinges.  This configuration allow bucking the hinge rivets without smashing the hinge assembly itself.  The bar worked well and the results look good.

Here is how the modifed bar fits under the hinge to access the rivet for bucking.

The final product looks good.

Next came backriveting the trailing edge.  This process was the same as for the rudder, with the exception that all the manufactured heads are on the top skin (no altering top and bottom).  I was able to do this by myself.  Again the results look good.

The outcome on upper and lower edges.

Here the sheer clips are being pop riveted into place.

After rolling the leading edge of the right elevator with Rich’s help, we cleco the two halves together.  We were only able to complete the left side with the time available today, but the final work on the right side will be done in a day or two.  More photos of the final product will be added later.

The week of November 24 (Thanksgiving Holiday) I spent time with Eric finishing up all elements of the elevator build.

After rolling edges, priming the surface to be covered was the next order of business.

Closeup of the final product before and after pop rivets.

The static wick nut plates install on the lower skin at the tip ribs.

Tip rib counterweights installed.

End results! They look good at a distance, but I really struggled through the elevators (see previous posts).  Now on to the tail cone section.

After many weeks of redoing the elevator trim tabs, adhesive bonding of the trailing edges and foam ribs was in order.  Rich came over to lend an extra pair of hands during the process.

Bending the angled trim tabs was accomplished with a simple red oak board cut to a 45 degree angle, then clamped to the angle iron jig.

Here the trim tab is sandwiched between two pieces of angle iron for bending the front part of the lower skin to 15 degrees.

A 12″ back rivet set was used with a standard backing plate to attach the lower portion of the trim tab spars.

Here is how the first set of trim tab horn rivets appear. More on the trim tabs later.

Cherry Max 3213-4-3 structural rivets were used to replace the simple LP4-3 called out in the plans. Discussions with my technical counseler and an A+P mechanic indicated structural rivets can always be substituted for lower strength rivets of the same size. However, Cherry Max brand rivets are more expensive (about 63 cents apiece).

On to the trailing edges – here the Van’s ProSeal equivalent is being applied initial application from with a caulking gun.  I later used a wooden popsicle stick to smooth out to ensure complete coverage.

This shows the foam rib attached to the rear spar.

Smoothing out the  bonding adhesive, getting ready to insert the trailing edge.

The trailing edge is clecoed to the angle iron jig about every 7th hole.  In between are wooden clothes pins, then comes a 2×4 with weights to hold the skins against the freshly bonded foam ribs.

The trim tabs were also bonded.  This photo shows them in the wooden jigs holding the skins against their bonded foam ribs.

DONE.  Now to let the adhesive cure for a few days before starting the final riveting steps.

This week I consulted with Terry Gardner on the best approach for handling the skin crease in the lower right elevator skin.  Just proceeding ‘as-is’ was one option, provided continual awareness of any crack development over time.  After considering alternatives, we decided to apply an external patch, drill out the adjacent rivets, stress relief holes, provide some bonding with a thin layer of ProSeal, and then apply new structural rivets all around.  Essentially this approach sandwiches the weakened crease line between the new patch and the internal rib. This may seem like a touch of overkill, but worrying about potential cracks on a new plane did not seem an attractive alternative.  Plus the time is right – the right elevator is basically wide open, I can get to both sides of the skins, and using structural rivets is preferred to Cherry rivets applied later.

Here is the effort for the week of October 5-11.

Another look at the offending location…

Pattern laid out to fabricate the patch.  Here I am using a scrap piece of .025″ aluminum.  The skin itself is .016″, so this should be adequate and easily use an AN426AD3-4 rivet for proper thickness.  The Advisory Circular AD43.13 page 4-20 was used to determine proper rivet separate for this plate (three diameters between centers).

Using the drill press to fashion the plate holes.

Deburr the holes with a hand-held cordless screwdriver and about 120rpm.  Notice the right hatching, this will be removed in the next stages to get the proper outer dimensions of the patch.

Used the patch as a template for first match drilling the skin holes.  Here piece is clecoed to the skin.  Not all the holes have been drilled in this picture.  Example, the lower left hole is clearly visible in white.

Here is how the skin looks after match drilling all the holes with the patch and the adjacent rivets removed.

This picture shows the stress relief holes drilled at the ends of the crease.  A #40 drill was used.  Fortunately the crease line is very well defined, not diffuse across the skin.  Next up is dimpling, bonding and riveting.

I had a little time available after skin drilling, so I started in on the rebuild of the trim tabs.  Here a jig for holding the rough-cut elevator horns is depicted (next to the roughed out patch plate).

Week of October 20 – A business trip to LA consumed over a week of my time. Before leaving I ordered a small one ounce quantity of ProSeal equivalent from Van’s for bonding the patch to the skin.

This stuff looks and smells just like the branded ProSeal version.  This container has a one hour set time, so moving expeditiously through the process is required. The white bottle contains the main compound, the foil pouch has a black colored catalyst.  The instructions call for uniform mixing with the wooden stick, and the final outcome should be a dark grey.

The mixture did turn dark grey.  The stuff is very sticky and quite thick, which made it difficult to spread thinly or evenly on the pieces. The patch has some of the rivets held in place with rivet tape for alignment with the holes in the skin.

Smeared and ready for back riveting.

Well here it is riveted, and then cleaned up.  Not too bad.  The final cosmetic verdict will be once primer and paint are applied.  My feeling is the structural elements of the patch are very solid.

Upon return from vacation I started the assembly of the elevator parts.  All went well until …. (more on that later).

Elevator reinforcement plates on inital assembly.

Adding the hinge reinforcement plates (those not already installed with the bonding strap nut plates).

Using a pneumatic squeezer and longeron yoke borrowed from Tal Halloway, a fellow RV10 builder.  The longeron yoke configuration is needed to get at both sides of the tip ribs.

Completed tip ribs, shown front and back.

Here it is – my big mistake on back riveting the lower right ribs to the skins.  Despite much care in alignment, the rivet head vibrated off the side of the backing rivet plate, resulting in me pounding the **** out of  the skin. Looks bad, thought skin was not broken.  I will have my technical counselor advise on path forward for this error.  In the meantime, I completed the left side back riveting with very good results.

Sheer clip install on left rear elevator spar.

Pop riveting the upper and lower left skins together with the ribs.  I used an old mouse  pad under the pop rivet tool for proper vertical alignment and keeping the tool from scratching the primed surfaces. The outcome was excellent.

The left side assembly through riveting the rear hinge is completed.  Again this part looks very good.  We shall see how the right side proceeds.

After work this week we finished off the Prekote and prime of elevator skins.  The most significant elements were masking off the scuffed area for foam ribs, and priming the riveted reinforcement plates for the static wicks.

Ready for primer…

Done.  Next step is rivet assembly.

All the elevator parts primed and staged for assembly.  Rita and I are taking vacation in the NC mountains this coming week, so maybe a few rivets will get set over the weekend when we get back.

I took a half-day from work on Friday, then spent about 15 hours over the weekend with the routine for wash, scuff, brighten, rinse, alodine, and priming all parts except the skins.  The process is the same as described in previous posts.  Here are just some pictures of recent events.

This photo shows the reduced cross-section on the special female 3/32″ die purchased from Cleaveland Tools.  Here the clearance from the screw recess is visible.  A picture of the regular die size is included for comparison. (see previous post on details)

Alodine applied to the skins where foam ribs will be glued with ProSeal.  This process is the same used for the trim tabs.

The garage is turned into a chemistry lab for the weekend…

Happiness is when friends and family participate in your favorites hobbies.  Rich and Eric both helped greatly on a long, hot weekend of metal prep and priming.