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Mounting the Emphennage
I had a hard time getting started on mounting my emphennage to the fuselage, because I didn't really know where to start. I'll keep a few pictures here, and add advice as I go along.
The first step is to get the fuselage level. I have a "Smart" level, that is accurate to 1/10 of a degree. It turns out my fuse has a 1/10 degree twist. I called Vans about the problem. They of course thought I was nuts, and told me that I should use a carpenters 6ft level, and a digital level was far more accurate then I needed. Below are some shots showing where I placed the level to true up the fuselage. Move it around to different points. The fuse is supported at the "false" wood spars, and under the tailwheel leg, and shimmed with aluminum spacers as necessary.
**NOTE: In the Orndorff video, George sets the incidence by putting the spacers on top of the skin on top of the front and rear spars. I found this out later, and was worried that my incidence may have been wrong, but further testing showed that they were less then 1/2 deg difference. I was told by a Tech Counciler not to worry.
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I seem to have gotten the fuse level and the
stab incidence perfect using the locations shown above. The next step was to square the HS
to the fuse. I determined the centerline of the fuselage by measuring across at the front
baggage compartment rear skin. I then transferred the centerline to the top of the curved
skin by using a square. I verified this by using a plumb bob with the string draped over
my center mark. The fuse has to be level for this to work. I then taped a long piece of
dental floss to this center mark, and attached a small weight, like a cleco or something,
at the other end of the floss. 
Mark the center of the fuselage aft deck,
and clamp the HS in place, making sure the front and rear of the HS are centered on the
aft deck. Now use the floss to measure to two common points at the ends of each side of
the HS. Floss has less stretch then string, but there is still some. I compensated by
laying the floss over a smooth surface, like my sharpie pen, and letting the weight
stretch it the same amount every time. I verified my results by using several points, and
verified the points by measuring their location relative to the centerline and rear edge
of the HS. I then double checked it by using a plain tape measure. Vans pre-punched holes
were right on the money, and I was able to use skin rivets as common points. It took .025
of shim on the right attach bar to get it square.
Lay a 1/8 spacer on the HS front spar, and a
1/4 spacer on the rear spar as per the plans, and check the incidence. Mine took 5/32 of
shim under the rear spar to get it level. At this point, double check that the fuse is
level, and the HS is level and square.
At this point I removed the HS (write down
how much shim you used!), crawled inside the fuse, and measured from the 810 bulkhead to
the rear edge of the 810C support angle. While you are in there, make sure your 810C is
wide enough to nest inside the radius of the longerons. You'll see why later. I then
transferred these measurements to the top of the aft deck, so I had an idea of where he
longerons and support angle that I was about to drill into were located. I then remounted
the HS, made sure the HS-814 was lined up fore and aft of the 810C marks I made, and
traced the edge of the fuselage skin on the underside of the HS-814. Now, with the HS once
again removed, I could measure where the holes needed to be drilled as per the plans. I
pilot drilled them to #40, then remounted the HS, re-checked all angles, and used a
12" #40 bit through the pilot holes and into the fuse. Put a cleco in each hole as
you go, take your time, and get the bit as straight as possible. I used 5 minute epoxy sparingly
to glue my 887 spacers in place so they didn't spin as I drilled. This was Chet Razer's
idea, and it worked great. The spacers popped right off when I was done, and the dried
epoxy came off with acetone.
Now came the problem. It seems that it is
very hard to impossible to make edge distance for the 3/16 bolt hole in the longeron and
the 810C angle. My 810C was nearly 1/8" short of the inside radius of the longer on
each side. I called Vans with the problem, and they said it was common, and that is why
the two inboard bolts are there. Edge distance is not critical with bolts like it is with
rivets, and there is nothing to worry about, so I press on. I used a needle file to
"fine tune" the pilot hole locations, and will have to final drill from inside
the fuselage with an angle drill. This part is a two person job, as you need somebody up
top to check your progress as you move up from one bit to the next, finishing with
3/16". Wedging my 6'2", 215lb frame into the tailcone was no easy task. Make
sure you wear earplugs and safety glasses, as it's very loud, and the drill blows all
kinds of debris around.
Here it is. With the help of RV-8 builder
Joe Matza, I managed to get the HS drilled and bolted in place. It is straight and sturdy.
The VS is only clamped in place for this photo.