Fitting the HS

Anyone have any ideas on setting the 0 degree incidence on the horizontal stabilizer? I have drilled the holes for the forward spar and bolted it to the fuselage. I followed Vans directions in placing a 3/16" drill bit under the rear spar and found that I have to force down the rear spar to obtain the spacing that is required. Is this normal? Also, I find it difficult to get an accurate measurement from the deck to the tooling holes in the stab. ribs. Anyone have a better way to check for the 0 degree incidence?
Thanks

If you are having to force down the rear of the HS to get it to lay on the 3/16" drill bit you must have some interference somewhere. It should lay down without issue. Make sure the HS skin/flange that is closest to the Fuselage skin has a small amount of clearance. Mine had about 1/64" on each side.

Shown on these 2 pics

Tooling holes

I had the same problem trying to measure accurately from the tooling holes.
In the end I inserted a #30 12" Long drill bit across BOTH tooling holes and then used the deprth guage (a ruler would do) on my vernier calipers to measure the height above the deck.
Measuring both the front and th rear tooling holes and a bit of Trigonometry and i established the angle of the Stab. It wasn't zero, but about 1/2 a degree, so I used a slightly bigger drill. Problem is that Vans dioesn't specify a tolerance. Zero degress plus or minus 'What".

Pete

Anyone have a method for doing this that does not require using the tooling holes at all? I tried using my Smart Tool digital leval but the H.S. is just too curved to get any kind of accurate reading...

I tried putting the 12" long bit through the tooling holes but just thought it was flexing and would like a better way if someone has one...

- Matt

Hi, Just did it. Went to Home Depot and bought 3/16 rod, cut a little longer than space in front and back. Put these in center holes and then measured with caliper. Had to use bits bigger than 3/16 but got the right angle of incidence. The measurements ended up within 1/128 in.
I am no expert but that is what worked for me.
Cheers,
Guy
RV7A C-GUYW

I just drilled mine a few weeks ago on my -9A. I drilled them with the shims in place and also the 11/32" (IIRC) drill bit under the rear spar. I clamped them to the aft deck mainly to keep the spacer from moving and it worked fine.

The problem I did have was that you need a longer 3/16" drill bit for the outer hole that goes through the longeron because otherwise your chuck will hit the stabilizer skin. When I drilled it, my bit wobbled a bit and enlarged these holes. The adjacent bolt holes have a nice fit.

I spoke to Van's a bit and they didn't want my to upsize that hole for an AN4, and said that the connection is mostly preventing uplift rather than shear, so it should be okay. I'm still trying to think of a way to make this a little better. Any ideas?