Empennage: Rudder. Spar riveted.

I decided to redo my rudder due to the trailing edge.  Here is the post outlining the new rudder.

The rudder spar is essentially complete and awaits its mating to the skin.  When I was ready to rivet the horn and its associated parts together, I noticed the plans had two holes that my parts did not, except for R-00917.  The missing hole on the left is critical for the tie clip, the right one must be for symmetry.

No such holes for me.

Thinking I may have missed a match-drilling step in the plans, I checked back and noticed nothing.  I needed those holes, so I match-drilled the holes into the spar and R-606PP using R-00917, then cleco'd on the horn to match drill it too.  After deburring and spot priming (above right shows the departure of some primer since I cleco'd without a full cure), everything came together just fine.

However, the rivet lengths called out for the plans are incorrect for the horn (including its nutplate).

My calculations (shown below) revealed more appropriate numbers (shown above in red).  Thicknesses were measured with my caliper.  I didn't have a -7.5 length, so I ground down several -8 lengths.  For the -8.5 (holds the nutplate), I could have ground down a -11 (the next highest length I had), but went with a -8 instead as called for in the plans. The shop head is a bit short, but hey, it's for a nutplate, right?

	1/8” Rivet
Rib/Spacer	0.035	0.035
Spar	0.035	0.035
Doubler	0.069	0.069
Horn	0.135	0.135
Nutplate		0.063
Additional	0.188	0.188
Total Length	0.461	0.524
Size (in 1/16”)	7.376	8.376
Rounded Up	7.5	8.5
Rounded Down	7	8

Here's the spar.  I'm just missing the counterbalance rib as I'm waiting for #10 dimple dies (dice?).  Ya, I could probably force dimple it with a screw, but tools are cool, right?