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Just started, already screwed up

Latech15

Well Known Member
6-3 - Vertical stabilizer - The instructions said to machine countersink the rear spar on all of the holes that are common to the skin and the inspar ribs (I think, tying from memory)

I machine countersunk (countersank? Countersunked??) all of the holes on the rear spar that are common to the inspar ribs, including the ones below the VS skin, except the one at the very bottom for the fairing. It looks like the side skin will rivet to these holes, and that they will probably need to be countersunk later on anyway, but I can't find it.

Am I ok, or should I order another rear spar and start over?
 
Post a pic so we can see what's up.

But at the end of your build, when you've become pretty good at this stuff, you'll wish you could go back and re-do these kinds of things.

Consider the few dollars for a replacement part just on-the-job training :D
 
Can double check for you tomorrow, when i am in the workshop
but if you take a look at 10-25
you will see that is 4263-3.5 rivets goes in there, which means that it will have to be countersunk.

Don't through it away just yet :)
 
6-3 - Vertical stabilizer - The instructions said to machine countersink the rear spar on all of the holes that are common to the skin and the inspar ribs (I think, tying from memory)

I machine countersunk (countersank? Countersunked??) all of the holes on the rear spar that are common to the inspar ribs, including the ones below the VS skin, except the one at the very bottom for the fairing. It looks like the side skin will rivet to these holes, and that they will probably need to be countersunk later on anyway, but I can't find it.

Am I ok, or should I order another rear spar and start over?

I'm not following which parts you countersunk inappropriately. Specifically what step (page and step #) did you mess up on? What part numbers are you referring to? Post some photos.
 
i did the same

I did the VERY EXACT SAME THING!!!!

I wrote to vans, they said just use the appropriate AN 426 rivet and build on. If I remember correctly, I had to order some AN 426 rivets as these are 426D4-* and I only had a handful of them. A quick order to Spruce or your favorite dealer of these type items and you are all set.
 
If you're referring to the holes in the aft spar flange below where the skin attaches, guilty here as well. The instructions are easy to mis-read.

The standard rivets that that attach the spar flanges below where the skin attaches are AN470AD 3-4. I was also advised by Van's to use AN426AD 3-4 and build on. These are the rivets that go into the spar caps from the spar flanges: the spar caps are also attached to the spar web and spar doubler in this area with AN470AD4-7 rivets so the structure is very strong.
 
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I always cross reference the instructions with the rivet call out on the plans. That will clarify the size and type of hole treatment required. The prints are accurate.
 
I always cross reference the instructions with the rivet call out on the plans. That will clarify the size and type of hole treatment required. The prints are accurate.

I'm unfortunately human and sometimes don't do what I "always" do. In this instance there's no rivet callout for the holes in question. Only a printed instruction to use a certain rivet size, last step of last page of section. The plans are correct, but it's one of those instances where printed instructions are somewhat subtle in the specific location of countersinks versus none. In any case, with one notable exception, I think all of us make these kinds of mistakes from time to time.
 
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Well I found the page in the instructions where those are to be riveted. I made the executive decision to go with the 426 Rivet’s instead of the 470. Glad vans agrees with me.

Now what does vans say about smileys in the skin......doh!
 
There are two exceptions: no countersinking starting with and below the bottom of the skin but also no countersinking above past where the spar cap ends.
You didn't mention the latter. The spar is too thin to countersink where it has no backing and therefore gets dimpled.
 
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