!#%*&@... Front HS Spar Ooops

I can't beleive I did this...

While riveting the front HS spar, I had a rivet with a shop head that was too small (I think I might have picked up the wrong size rivet). It was the only blemish to an otherwise perfect riveting job, and I just couldn't have one bad rivet, I felt compelled to fix it. In hindsight I wish I had just left well enough alone!!!

I decided to drill it out and replace it, so I flipped the part over on the bench, and then walked over to my tool chest to grab my drill. I then walked over to the part and proceeded to drill. I flipped it back over only to find out I had just drilled out the WRONG rivet. When I re-riveted the hole, I bent the rivet over badly (grrrrr), so I drilled it out (again). Unfortunately, I had to drill the entire rivet out to remove it. When I flipped the part over I found that the back side of the hole was now enlarged (egg shaped) and I had now violated the 2D edge distance on the HS Spar Reinforcing Angle HS-710 by a pretty big margin (it was pretty close to begin with). Now the explatives really started to fly!!!

I called Vans this morning and sure enough, due to its critical nature, HS-710 needs to be replaced. [Insert more explatives here]. That's about 14 good rivets to drill out, and now I have to fabricate/replicate HS-710!

Scott (at Vans) gave me the impression that the enlarged holes in HS-405 (rib) and HS-702 (front spar) are not as much of a concern as the edge distance on HS-710. One thing I forgot to discuss with him is... should I be concerned with a minor edge distance infraction (say 1.5D) on the front flange of HS-405? I would like to avoid replacing that part as it is match drilled to the skin, but I will if I have to. Your opinions??? I am not sure I even have problem there as the hole enlarged away from the edge, but if it might be an issue I might just have them throw an HS-405 rib into the order before it ships.

Moral of the story... Vans says to leave minor rivet problems alone and build on... trust me, they are right!!!

Regards,

Can't answer your technical question, Brad, because I'm building a 9 and don't remember exactly to what parts you are referring, but hang in there. I rebuilt half of my HS, including an entirely new front spar and right side skin, because I wasn't happy with a couple rivets on my front HS nose rib-skin rivets. Cost be about $275! Ouch. If there is any question in your mind (or will be in the future) and especially if the parts aren't too expensive, I would think about replacing it. At the same time, if you get some good suggestions on how to remedy it, don't be afraid to do that as well, especially if Van's endorses it.

Don't worry, you'll get so much better as you go along that you won't make as many mistakes that require replacement of parts. Been there, done that as have a lot of builders before me.

Good luck.

Steve, thanks for the words of encouragement.

For others that may read...
As a clarification, it isn't so much that I don't want to take the time to relace the part, but more an issue of trying to avoid further problems. While in general I would say a rivet with 1.5D edge distance is near unacceptable, I am wondering if the potential problems created by replacing the part are less than the potential problems created by the original problem (in this specific situation). In other words, replacing this part for one bad hole means I have to drill out several more rivets and match drill the structure and skin again. Certainly not the end of the world, but it opens the door for more issues (on currently uneffected parts). Remember, fixing something that might not have been a big deal is what got me into this mess in the first place... I am trying to learn from my own mistakes. ;-)

Response from Vans

Well, I called Vans again to ask them about the edge distance issue on the HS-405 forward flange. It went something like this...

Me: Hi, I want to talk to you about edge distances on the HS-405 forward flange.
Vans: Build on.
Me: Ok, but see...
Vans: Build on!
Me: But... I... but....
Vans: BUILD ON!

Ok, so I will build on.

I guess this is one of those spots where sacraficing a little edge distance on one part (HS-405) is acceptable to ensure edge distance on a more important part (HS-710).

build on

brad --

if you haven't got to the rudder yet, be careful when trimming the horn, as per the drawing. i cut from center of hole to center of hole, but by the time i had edge finished the part, when i match drilled it into the lower rudder rib, there was insufficient edge distance. i called van's & they asked if i was building a 7 or 7a -- when i said 7a, they said build on, not critical. however, it was only a ~$10 part, so i elected to replace it anyway.

for drilling out universal rivets, the "rivet removal tool" can't be beat. basically it's similar to a microstop, with a cup that fits over the rivet head to guarantee centering of the bit. most of the tool shops have them -- i found the cheapest was either ats or spruce, i forget. doesn't help on 426's, though. for them, i usually start with a smaller bit. anyway, good luck with the rebuild. i'll bet it comes out o.k. because you will be "extra careful" on doing it.

john
7a-wings (fuse ordered)

RV7Factory said:

Me: Hi, I want to talk to you about edge distances on the HS-405 forward flange.
Vans: Build on.
Me: Ok, but see...
Vans: Build on!
Me: But... I... but....
Vans: BUILD ON!

Click to expand...

Ok, well, maybe they're right but let me relay a story about a recent series of tornados in these parts. We have tornado sirens so wheneve rthere's a sighting, they go off and people head for cover. At least that's the way it's supposed to work.

A week or so ago, all heck was breaking loose and wind was blowing, debris was flying all over the place and a bunch of people were looking out the window. "Are you folks crazy?" I asked. "Does this <i>look</i> like a safe spot to be?"

"It's OK," one responded, "there aren't any tornado sirens."

The point? During the course of the project there will be times when a little voice will say, "this isn't right" or "this isn't good enough." For the most part, someone will always tell you to "build on." Sometimes -- perhaps even more often than not -- they'll be right.

But you'll be the one flying it and <i>you're</i> the one that's going to set the standards for what's acceptable workmanship. If you have a concern about it, don't wait for the tornado sirens. Follow your instinct.

John, thanks for the heads up. Your post has been printed and will be reviewed when I get to that task. Good advice.

Bob, following my instict is what got me into this mess!!!