I marked everything to ensure minimum edge distances and checked many times before drilling through the skin.
First I figured the location of the doubler on the spar and match drilled this to locate the doubler properly. I had to increase the joggle a bit to fit it.
I ran lines up the doubler from the lower rivet locations to confirm edge distances were okay. I ran lines up the skin the same way in the same place on the outside of the skin.
I trial fitted the doubler with skin on top, and marked on the inside the doubler location. I also put the angle I fabricated on the inside and marked it's location on the doubler and rib.
Then I took it apart and put the angle in place on the rib using the jig you see in the first picture. The goal was not to set the location on the doubler; it was solely to get the angle placed on the rib properly, offset back to keep the doubler flush. Angle to rib holes were drilled.
Then I put it all together again with the angle on the rib, doubler in place, and skin on top. Marked on inside and then took apart. Confirmed that all edge distances were good and my marks were good.
Put it all together again, and drilled the hole at the top left on the doubler. Took it apart and checked all good. It was. Did same with doubler top right. Checked good. Then drilled the rest of the doubler holes with confidence.
When I disassembled all the overall assembly was perfect with good edge distances and as you can see it is very true and flat.
I will have to modify the washer plate to accommodate the two lower rivets on the upper half but I'm good with that. If the washer plate had been longer I could have incorporated it into the upper rivets but it just wasn't.


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Ser 104142, RV-14A flying - N1463

Ser 83825, RV-8 building - N8638?

USN Ret, Urologist, AME, Repeat Offender