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 I have very few pictures of the RV-7 rudder construction.  I'll try to do better as the RV-8 goes together and we'll fake it.  As in every other operation, Dan Checkoway has exceptional documentation.

Rudder construction begins by making little pieces out of big pieces.  Using the reference notches in the angle stock, cut the rudder skin stiffeners apart.  Mark the taper on each one and trim by whatever method suits your tools and skills.  Note that the forward end of the stiffeners must be checked and trimmed to a maximum length as indicated on the prints.  Also note that the hole pattern is irregular - each stiffener is pre-punched to go in a particular place.  I marked with a Sharpie and straight edge, trimmed with snips and filed until smooth, then finished with the ScotchBrite wheel.  There should be no evidence of the guide notches when you're finished.

Cleco and ream the stiffeners to the skins, disassemble and de-burr carefully.  Use a very light touch when de-burring the 0.016" rudder skins - it is very easy to over-do it and end up with a sharp edge inside the holes. 

Dimple the skins and stiffeners.  This happens to be the RV-8 rudder skin, but by and large, dimpling is dimpling...  Clean and prime if desired. 

The rudder is your first opportunity to do some back-riveting.  Elevate the skins off the table and insert a rivet in each hole.  Use rivet tape to hold the rivets in place.  Turn it over, position the stiffeners and pound away.  (This is the right elevator skin from the RV-8 - the RV-7 rudder skins come in two pieces, so you don't have to fight the TE fold.)  Set the skins aside in a safe place. 

Cleco the bottom rudder rib to the rudder spar.  The 0.125" hole in the forward flange of the rib will mate up to a hole in the spar.  Use a Unibit to hog out the holes to 0.375".

Here's you first opportunity to make a part from scratch - make the shim shown in Drawing 7.  That was tough.  (I wish I had a small shear.  I think I used a hacksaw.) 

Bolt the rudder horn in place and match-drill the four top holes.  Remove the horn from the spar and cleco the rudder horn to the bottom rib and radius the horn to clear the rib flange.  Match-drill the four holes in the aft edge of the horn.  Take it apart.

Cleco the spar, bottom rib and rudder horn together, then slip the shim in place, clamp and match-drill the shim.

Cleco the reinforcement plates in place on the spar and ream.  Prepare the tip rib and counterbalance rib, cleco them to the spar and ream.  Add the counterbalance skin and match-drill to #40.  Cleco the skins to the skeleton assembly and cleco the AEX wedge in place.  Ream all holes to #40.

Trim the rudder brace per the prints, cleco in place and match-drill.  Fabricate the rudder bottom attach strips and match-drill to the rudder assembly.  Take it all apart and de-burr and dimple as required.

The plans direct you to ream and dimple the three aft-most holes at the tip of the skins to #30 for later attachment of the fiberglass tip with blind rivets.  I planned all along to use #6 screws to attach the fiberglass parts, so I followed the instructions.  If I had it to do over, I'd ream and dimple for #40 and use #4-40 screws and nutplates.

Match-drill the lead counterweight to the counterbalance rib, countersink and dimple the parts as required.  Countersinking the lead free-hand is easy enough with the de-burring tool or a countersink cage, but big-screw dimpling may not be so obvious.  I didn't buy a #10 dimple die - I doubt I'll make more than a dozen #10 dimples throughout the course of this project.  Drill a #9 hole in a block of hard wood - pine or poplar won't cut it.  I used a scrap chunk of oak.  In the same way you countersunk the lead, use the de-burr bit or a countersink cutter in the countersink cage to hog out a dimple in the oak.  Clamp the oak in your vise and slip the #10 screw thru the hole in the rib and into the oak block.  Pick up your rivet gun, mount a flush set and bump the screw until it forms a dimple in the rib.  Adjust the depth of the cut in the oak block until the dimple in the rib is just deep enough to set the screw flush.

Countersink the AEX wedge on both sides to clear the dimples in the rudder skin trailing edges.  You'll end up with a nasty-looking egg-shaped hole.  It's ok - promise.  Prime anything that you think needs it.

Cleco and rivet the reinforcement plates to the spar, then cleco and rivet the bottom rib and it's associated parts.  The prints indicate that pop rivets are acceptable in the horn brace, but I was able to buck all but two of them.  Cleco and rivet the tip/counterbalance rib to the spar, then cleco the counterbalance skin in place.  Rivet the counterbalance skin to the rib, but not the spar, then mount the lead and torque the screws.

Be sure the TE joint surface of the skins is clean and free of primer, then cleco both skins to the spar.  Set the 18 rivets that join the counterbalance skin, rudder skin and spar.  Cleco the tip rib in place and fasten it with blind rivets.

Rivet the rudder skin to the skeleton.  The last few rivets in the TE of the ribs will require a thin-nose, no-hole yoke on your squeezer or a very thin bucking bar.  A piece of 1/2" x 1/4" steel bar stock clamped in a vise with a very short stub hanging out of the jaws makes a descent anvil for pounding rivets in the TE of the rudder ribs.  If you use this method, you'll want a little help holding and balancing the rudder while you set the rivets.

The rudder trailing edge is a challenge for many builders.  It's not hard to do, but can be difficult to work yourself up to actually starting.  I used the TE hole pattern to match-drill a piece of 1x1x1/8" aluminum angle stock, then dimpled the skin TE holes.  Test-fit the AEX wedge in the TE and correct any high spots.  Clean the AEX wedge and TE joint surface with MEK or acetone.  I used 60-minute epoxy to bond the AEX wedge inside the rudder TE.  Cleco the now-sticky-and-gooey TE assembly to the angle that you drilled earlier, stand it on the LE and leave it for a few days. 

Once the epoxy cures, you can remove the angle and clean up the excess.  I propped it all up and shimmed until the TE would lay flat on my back-rivet plate.  Find the center of the TE and stick a rivet in it.  I used my flush set to form the double-flush shop head in the dimple.  Rivet the tip and bottom holes in the same fashion.  Some folks alternate the factory head left and right as they work their way out the TE from the center.  I didn't bother.  Pick two of the three rivets you just set and find the center between them.  Put a rivet in the hole and set it.  Continue halving the empty spaces until you've filled all the holes.  With a little care, you'll have a rudder TE that's dead straight.

Finish the rudder by rolling the LE.  I used duct tape to fasten the LE to a piece of iron pipe.  Then wrestled and twisted and cussed until it had a generally curved shape.  Then I removed the pipe and tape and squeezed, pushed, shoved and generally harassed it until the two runs of rivet holes came close to lining up.  Cleco the two LE flanges together and ream the holes.  De-burr the holes, bend the edge if desired and use pop-rivets to finish the LE.

I'll discuss the fiberglass tips later.