Clarification on a few drilled holes for the horizontal stabilizer

[charrois]

Hi everyone. I've built an RV-10 before and have now just started on an RV-8 with my son.

I have a couple of questions with regards to some of the drilled holes for the horizontal stabilizer spar. In Sec D-D, it references 470AD4 rivets to attach the pieces together, yet in the plans when it had us drill those holes, they were drilled to #40. Assuming the rivets really should be AD4 like the others in the area, those holes should be drilled #30. Did I miss a step, are they to be enlarged at a later stage, or was it just a typo?

Also, there are a number of rivets (8 on each side) that go through the HS-00003 to HS-702 to HS-810-1/HS-814-1, towards the ends of the HS-810-1/HS-814-1, that will have to be match drilled to accept the AD4 rivets that are called out, yet we didn't see anywhere in the instructions to do so. Again, is it something we just missed? I know from building the RV-10, in general, if they didn't tell you to do something at a particular stage, they usually had a good reason to hold off doing it. But the RV-8 plans might be a little more "loose" in this regard, so I'm wondering if these things should just be done now. I've noticed that sometimes the plans/diagrams don't line up exactly with the exact parts we are given (different versions?) in that some of the parts were missing pre-punched holes in some locations that seemed to be in the diagrams, requiring match drilling instead of final drilling. Not a big deal at all; it's just an issue of getting used to the precision of the plans.

Thanks!

 

[N804RV]

I think SB-14-01-31 might clear some of this up for you.

https://www.vansaircraft.com/service-information-and-revisions/sb-14-01-31/


Also, throughout the HS, skin to rib/spar flanges are all pretty much AN426AD3 rivets as far as I remember. If its a universal head its part of the supporting structure and mostly AN470AD4.

 

[Taltruda]

The -8 instructions sometimes miss little details like you discovered. They often have you initially drill#40 holes, then letter when you determine the time is right, you match drill #30, then disassemble and deburr. I haven’t built a 10, bit I hear it kinda spoils you.

 

[RYOUNG]

You are in an area of the build that requires extra due diligence as you proceed. It is very easy to end up with edge distance issues with the #30 holes through multi-layered parts if not careful with layout. Good luck.