Possible Manual confusion with respect to part VS-410PP

Post by **Spike** » Fri Jan 14, 2005 12:25 pm

In workup up the Vertical Stabilizer and reading over the drawings and manual, Ive come over a bit of confusion with respect to the usage of those heart stopping words, "drill in assembly".

For the RV-9, the manual points out that not all of the holes in the VS-410PP hinge brackets have been drilled. We are to cleco the top one in place and back drill those holes through the pre-punched holes in spar/doubler. However, the manual then proceeds to say that the bottom corner holes on the lower VS-410PP should be "drilled in assembly for their bolts."

AH HA! We have a slight problem here in that this piece is different based upon the gear configuration of the build. If you are building an 'A' variant then those two lower outside rivet holes do get drilled and riveted. If you are building the other variant those holes do not get drilled due to the proximity of the bolts that go through the mounting plate on the tail wheel assembly. The confusion here is that there are 2 sets of lower corner holes. One for rivets (in the 'A' variant) and one for bolts. So, tell me Van's, which ones are you to drill in assembly?

It seems pretty obvious that if your building the taildragger then you have to drill those holes in assembly because the bolts go through not only the VS spar and the gear mount, but also the rear bulkhead. However, if your building an 'A' variant those two rivets are no different than any of the other spar to hinge rivets.

My conclusion on this is that vans' use of the evil "drill in assembly" language really only applies to the bolt holes used in the conventional gear setup. Do note though that if you are building a trike, you will still have to drill two additional bolt holes "in assembly" later on in life for the tail tie down bracket. However, we can ignore that for now. Since I know for sure that I am building a trike I dont see a reason not to match drill those holes now and prep them just like every other hole in spar/doubler/hing assembly.

Any other 9 builders care to offer support or disagreement to my interpretation of the plans?

-- John

mustang · Post by **mustang** » Sat Jan 15, 2005 2:44 am

John,
I'm looking at that very thing myself and scratching my head. I've got the rear spar built up but since I'm building an "8" taildragger I'm not sure what to do either. It shows a lonely little rivet at the bottom of the spar that I am wondering about. So far I have not even drilled the hole for it. I must spend more time reading the plans.

I think drawing 27 has some answers for the trike.

Cheers, Pete

Post by **Spike** » Sat Jan 15, 2005 8:24 am

Pete, the more I thought about this yesterday the more I was convinced that my interpretation is the correct one. Just to back myself up though I took the drawings to another builder and he agreed with me. I am going to move forward and drill all 6 rivet location in the bottom of that hinge plate since I am building the trike. The drill in assembly for bolt holes in the manual seems to only apply to the tail dragger. Is this the same for the 8 also?

Dan A · Post by **Dan A** » Sat Jan 15, 2005 6:13 pm

Pete, If you are talking about the horizontal stabilizer spar, do not drill those holes until you have the fuselage built. drawng 3PP shows this as you are setting the incidence angle with the fuselage. If you are talking about the vertical stab. rear spar, drill when you are fitting the tail wheel assembly and have it all clecoed together. See drawings 6PP and 27 (comes with the fuselage but you have a small drawing in the back of the book). That may make more sense of it. Good luck! I did mine about 2 years ago,
Dan

Dan A · Post by **Dan A** » Sat Jan 15, 2005 6:20 pm

Spike, The holes you "drill in assembly" are also for aligning the vert. stab. sith the fuselage. Wait until you have the fuselage built before you drill them so you can align it correctly. As with peter, check the prints in the back of the manual. I have found them to be a very good resource. Dan

mustang · Post by **mustang** » Mon Jan 17, 2005 3:26 pm

Dan,
OK, Thanks. The latest instruction sheet does not mention these holes in the VS but I wanted to be sure that I was not omitting anything that would be more difficult to drill later. I am just about to rivet my vertical skeleton together so.....
Thanks again,
Pete