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Elevators
It looks like I don't have a single photo of the RV-7 elevator construction. I'll add some from the RV-8 as I get to
it.
 Just like the rudder, elevator construction begins with the stiffeners. Use snips to cut the stiffeners apart, then mark
and remove excess at the trailing edge. Smooth the edges with a file. Then radius the corners and remove the burs
with the ScotchBrite wheel in the grinder. I didn't bother to separate and mark the pieces as left/right and top/bottom.
  Cleco the stiffeners to the skins and ream
the rivet holes to #40. Disassemble
and de-burr the parts.
  Dimple
the skins and stiffeners (even my brother-in-law Nathan can use the
DRDT-2) and prime if desired. Back-rivet the
stiffeners to the skins.
 Here's a step that I
messed up - before you rivet the right elevator access plate doubler to the skin,
you need to rivet the CORRECT nutplates to it. So, ream and dimple the E-615PP doubler plate, then clean up the edges.
Prep and prime if desired, then rivet the K1100-06 countersunk nutplates in place. Then back-rivet the doubler to the
skin. If you mount K1000-06 plain nutplates, you'll get to drill the doubler out and re-do it, because you can't reach
the rivets that hold the nutplates to set them.
 Use the
brake you made to bend the elevator skin trailing edges so that the leading edges just touch the spar without help from you (or
gravity). Be sure to keep the skin tucked back against the hinge-point as you bend. If it slides forward, it will
tend to bend too far forward, resulting in a humped TE.
The instructions direct you to prepare and rivet the right elevator before starting the left one. Other than the cut-out
for the trim-tab, the process is essentially the same for both.
 Cleco and ream the
reinforcement plates and nutplates to the elevator spars. Flange and flute the end and counterbalance ribs, then cleco
them together and ream the rivet holes. Cleco the assembly to the spar and ream the holes, then remove it.
The counterbalance photos that follow are from the RV-8 and are different from what's shown in the plans. On the RV-7, I
basically followed the plans and whittled the lead until it fit inside the fiberglass tip, which I modified by adding a
bulkhead to close the forward face of the tip. I don't like the idea of wrapping the fiberglass around the lead and
facing the open end into the wind at 200mph, whether it's glued and faired with epoxy and micro or not. I want my tips
removable, so bonding the open end of the glass tip to the lead is not an option.
 On the RV-8, I have decided to again follow the plans but modify the lead by cutting the rounded end off flush with the faces
of the ribs and use a bolt thru the forward tooling hole to add weight as necessary to balance. Not radically different,
but should drastically reduce the hassles of fitting the lead and fiberglass.
 With the
tip rib and counterbalance rib clecoed together, position the lead counterbalance weights and add the counterbalance skins.
Drill the forward faces of E-713 and the lead weights to #12. On the RV-7, I drilled the holes free-hand (because my
drill press was in another state) and wound up with crooked holes. For the RV-8, I used the pre-punched guide holes in
E-713 to mark the hole locations on the lead, took it apart and used my drill press to get a straight hole thru the lead.
Then I put it all back together and used the #12 hole in the lead as a guide to drill the bolt hole thru the forward flanges of
the ribs. Use lubricant or lead will stick to the drill. Remove the lead weights.
 Take the lead out of the assembly and put it back together. Cleco the counterbalance assembly to the spar and ream the
holes to #30. Cleco the root rib in place and ream the holes to #40. Cleco the skin to the skeleton, noting that
the elevator skin lays on top of the counterbalance skin.
  Remove the clecos holding the root rib to the spar, cleco the elevator horn in place and ream the rivet holes to #30.
Ream the elevator skins to the spars and ribs and take it all apart. De-burr the holes and file and smooth the edges.
The cut-out in the left elevator skin and the bottom flange of the E-606PP spar are dimpled and the top of the spar is machine
countersunk for -3 rivets.
  Disassemble, de-burr, dimple and prime as required. Note that four holes on each elevator must be machine countersunk to clear the
elevator horns.
  Rivet
the right elevator first - because it's a little easier. Rivet the tip rib and counterbalance rib together, then rivet
the inboard ribs to the spar, flush heads forward. Rivet the reinforcement plates and nutplates to the spar.
  Rivet
the outboard ribs to the spar, then rivet the elevator horn to the spar. Rivet the counterbalance skin in place and
loosely mount the lead weight. The prints indicate that you should hack a chunk out of the lead before mounting it - I'd
recommend you wait until final fitting.
 Position the skeleton inside the skin and cleco in place. Rivet the counterbalance skin to the skeleton, then rivet the
rest of the skin in place.
Repeat for the left elevator, but add a few steps for the trim-tab structure.
The lists are littered with tales of builders trashing three or four trim-tabs before either lucking out, giving up or making
do. I conscripted Dan Horton and his box-brake to help me bend the trim-tab. Mine isn't perfect, but it's
considerably better than what I could have done on my on with blocks and tape. Once the tabs are bent (or cut off...)
cleco the trim-tab spar to the bottom surface of the trim-tab, then clamp the control horn in place and drill. Take it
all apart, de-burr, dimple, countersink and prime as required. Cleco it all back together and rivet per the plans.
  The
instructions direct you to cut some tapered blocks to match the angle of the
TE and clamp it all to a table to bend the close-out tabs. I had poor
success with this step on my RV-7. I tried again on the RV-8 and had no
trouble at all. The 200 hours of banging on aluminum in the interim
probably had something do do with it. Use some form of double-sticky
tape to keep the
blocks from slipping under the clamp pressure and vibration of bending, whether with a hammer and blocks or rivet gun.
Clamp it TIGHT.
 I used my
2x rivet gun with the 3/4-inch flush set. Turn the air pressure down low - like less than 20 psi - and and keep the set
close to the bend line. Run the set down the bend line while tapping lightly and the tab will just fold over.
Some builders just cut the tabs off and fabricate close-out ribs rather than fool with it.
Bending the tabs on the RV-8 elevator skin went so well I decided to try the trim tab.
    Bending
the trim tab ends is basically the same, but the pieces are smaller and easier to handle.
 Countersink
the holes in the top of the trim tab spar and dimple the bottom. I used a back-up plate to guide the pilot when it
penetrates the spar.
  Fit,
dimple and rivet the control horn to the trim tab. I had to use a blind rivet in the aft-most hole of the outboard half
because there was simply no room to buck it with anything that I could find around the shop. My neighbor Nathan Boyd was
kind enough to help me pull the rivet. Dimple the holes for the spar flange.
 Now you
can rivet the trim tab spar to the bottom half of the skin. Measure, position, clamp and drill the aft half of the hinge
to the trim tab. Mark the excess, take it apart, trim and de-burr, then cleco it back together.
Pin the forward half of the trim-tab hinge to the tab and clamp it to the elevator, adjusting for alignment and clearance per
the drawings. Match-drill and cleco the hinge to the elevator, clean it all up and rivet the trim-tab. Rivet the
forward half of the hinge to the elevator.
Roll the elevator leading edges. I used duct tape and a chunk of 1" galvanized pipe to roll the LEs. Get some help.
Be careful to hold the elevator in place on the table and roll the bar into the sheet, without making a crease down the length
of the spar flange. Work the roll until the rivet holes line up with little or no force, then ream, de-burr and
blind-rivet.
Install the rod-end bearings and jam-nuts and test mount each elevator to the HS. The instructions direct you to trim the HS spar flange as necessary to
get the required DOWN deflection, but do not cut into the HS spar reinforcing bars - I'd wait until fitting the tail to the
fuse to trim the spar flanges. The instructions also direct you to drill
the elevator horns now for the center bearing bolt. Some builders recommend waiting until the assembly is mated to the
fuselage. I drilled as directed, but in hindsight, would wait till later.
I'll cover the fiberglass tips elsewhere.
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