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pilot10011

I'm New Here
I bought a second hand RV-8 Empennage kit a while ago and am finally starting in on it. The previous owner only got to page 3 of the manual. Everything looked good back when, but tonight I discovered a few flaws. Vans is closed till Monday and I'm hoping you guys can put me at ease...

1) All the ribs/skins on the left HS except 708 were match drilled with #30 instead of #40. I presume I could just use 4-4 rivets on these and live with the cosmetic flaws, but could I possibly use NAS1097AD4-3.5 oops rivets for all of them?

2) A couple ribs were match drilled without being fluted. After I fluted them I had the bad feeling that they might not match up now.

3) The two forward top/bottom holes on HS-405 that go to the skins are really close to the front edges. The left #30 drilled holes are less than a hole from the edge and the right #40s are probably right at one hole width. I see now that these holes are a reoccurring problem, but it seems like these are closer than most.

Any thoughts would be appreciated. Thanks in advance.
 
I'm no expert but I'll reply. I think you are fine going up a rivet size if the holes were mis drilled 1 size up. As far as holes being misaligned...nobody can even guess without seeing some decent pictures of what you have going. Do you have a decent camera?
 
I figure the only real way to see if the non-fluted ribs will still matchup is by actually trying it out. I will do that later today.


I've heard that you are not supposed to use oops rivets for more than 3 holes in a row, but I have not seen an official document stating such. Does anyone have one? I sent an email to Vans to see what they say.


Below is a picture of HS405 showing the edge distance of the #30 drilled holes. Both holes on this piece have the same distance. The other side is #40 drilled, so it has more.


http://i1293.photobucket.com/albums/b584/pilot10011/RV-8/20130126_183014_zps2e63b6b6.jpg
 
Aft hole in picture

It looks from the picture that the is a MED issue with the last hole of the rib flange. I would definately call VAN's tomorrow and get a new rib. I had to do that with a couple of pieces in the emp kit.

Cheers,

Don
 
I discussed edge distance of this joggled flange...

.........with Vans a long time ago, since even with a number 40 hole it did not seem to meet edge distance requirements for me. I believe there are other posts on here that describe the same problem. Van's told me that for this one hole it was acceptable, but again that was with a #40 drilled hole. Best advice is to contact Vans, but I would also be leary of MED with any other holes that may have been drilled incorrectly to #30.
 
Oops rivets have a smaller diameter head than a "normal" rivet so they blend in with the rivets that are next to them. This makes them weaker than "normal" rivets because the manufactured head contacts the skin with a much smaller area in proportion to the shank. Using one or two in an RV rivet line is not a big deal because the other rivets in the line provide most of the strength, but if you use more than that, your structure will be weakened.
 
I received my response from Vans today.

As we thought, I cannot use all oops rivets. I will use 4-4.

They said I can leave the ribs un-fluted if it looks like it'll create a problem. I already fluted them though. So far, they still fit on the left HS....

I was told not to worry about the edge distance on HS-405.

Thank you everyone for your input.


The build continues.......
 
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