Elevators 9-12-1 to 9-12-6

Now that the rear spars were attached to the ribs, it was time to rivet the skins to the rear spar. Again, I started on the bottom right skin and set the rivets along the open side of the spar using the pneumatic squeezer. 

I did leave the last 4 holes open as I will later need to reach inside to rivet the gusset to the root rib. The plans don't specify leaving these 4 holes open (only the holes along the forward spar) but I figured I would have some additional flexibility reaching inside if I did so, and I can finish riveting those later as I won't lose access to them.

Rear spar riveted to bottom right skin

Next up I riveted the skin to the rear spar along the underside of the skins behind the trailing edges. These had to be bucked, but this was relatively easy with the rear spar placed at the edge of the work bench as the plans illustrate. All bucked rivets came out really nicely.

Bucked rivets along the rear spar to the skin...

...and from the top side rivets and skins are flush and flat

Now it was time to position the remaining two skins on top of the first and start riveting them together. As I lay the skins together, I made sure that the rib halves and close out tabs on the skins were aligned correctly, and then clecoed the skins to the rear spars.

I decided to skip ahead a couple of steps and rivet the rib halves together first because this would give me a little more flexibility in fixing issues if anything went wrong while riveting the ribs in the tight space available. I started by clecoing each end of the rib halves together from the web side. I decided that I would pull rivets from the flange side as that gave me a little more room to manipulate the hand rivet puller. 

Working on one rib at a time, and from inside outwards, I was able to pull all 4 blind rivets without any issue, and didn't need to make the spacer tool specified in the plans. All rivets were set perfectly, and I am very happy with how the manual rivet puller performed.

Manufactured blind rivet heads on the rib flange side...

...and blind rivet  shop heads nicely set on the web side.

Continuing on with riveting the rear spars to the elevator skins, I began by riveting the bottom left skin to the rear spar in the open area where the trim tab will be attached using the pneumatic squeezer. 

For the remainder of the skin to rear spar rivets behind the trailing edge, I had to make use of a special bucking bar (that I purchased as part of my kit from Cleaveland Tool) to set the rivets due to the tight spaces involved.

Bucking bar for setting the rear spar to skin rivets on the elevators (taped so as to not scuff the primer)

Following the plans on placement of the bucking bar relative to the spar/skin, it was not too difficult to set all the rivets. I did find that I had to increase the air regulator to the rivet gun by 2 notches, and also had to buck for several seconds several times in order for the rivet to set fully, but all rivets came out nicely.

Due to not being able to see the bucking bar on the rivet while riveting, the bar did slip off a few rivets while they were being set, but other than some very minor deformation (that I flattened out) of the shop head on one side, this was not an issue. 

Rivets bucked on the bottom left skin (bottom row)

Once the rear spar was fully attached to the bottom left skin, I felt confident enough to tackle the rivets using the special bucking bar on the top right skin. These all turned out really well, and I felt I had much better control after my earlier round on the bottom skin. 

Rivets bucked on the top right skin (top row)

Rivets seen from the outside, all set nicely


Build Hints

  • When pulling blind rivets in tight spaces, determine orientation of the rivet to allow pulling in a direction that maximizes the space available for rivet squeezer to operate. That may remove the need to fabricate a spacer tool to help in pulling the rivets fully.
  • The special elevator bucking bar requires an increase in rivet gun pressure and longer bursts of riveting to fully set the rivets. A 2 notch increase in the air regulator setting worked well for me.
  • Pay special attention to the special elevator bucking bar moving slightly while riveting. A small movement where it is being held can translate to a much larger movement near the shop head and may result in the bucking bar slipping off the side of the rivet as it is being bucked.
Time Taken:     6.5 hours
Dates:                December 6 - December 10 2022

Elevators Total Time:           63.9 hours
RV-10 Build Total Time:      227.6 hours

Priming Total Time:                     24.8 hours (not included in build time totals)