If it really is mission critical to set those rivets slightly high it should be specified in the manual.
It's not. What is critical (if one cares to do it right) is for the rivet to not sit low in a countersink. If it does, when the rivet is installed, it can not be set with it sitting tight in the bottom of the counter sink. If this is still not clear, take another look at
Dan's detailed post. Particularly the diagram at the bottom.
If you had countersunk to a depth that resulted in the rivet being exactly flush you would have done what the manual said, and it would have done what is detailed on page 05-08 in
Construction manual Section 5 If you look at this document you will see that it shows the hole knife edge if machine countersinking on .032 material. It also says that for material that is .040 or thinner, dimple countersinking is preferred, but that in certain instances you can machine countersink as thin as .032 for an AD3 rivet. That is what is recommended in this location because of the reason stated previously.
I only mentioned 1-2 thousandths high would be a way someone could assure they did not have any that were too deep. In reality, just a few slightly deep would probably not be a big deal. You said you purposely made them all deep and some were even deeper. If that wasn't actually the case then you might have been fine.
Building RV's is a learning process. Very few of us have the skills and knowledge required when we first start (myself included). Chalk this up as a learning experience.
Here is a tip I developed many years ago to that can be used as a shade tree method to determine how deep a countersink is.
- Countersink a hole
- Insert a rivet
- apply a piece of vinyl electrical tape over the the rivet (do not stretch the tape) and rub it down well.
If you see a raised spot in the shiny surface of the tape, the C.S. is too shallow. If you see a low spot in the tape, it is too deep. If you can see nothing (can not see where the rivet is under the tape) it is probably perfect.
The unfortunate thing is that I would guess you countersunk deeper because some well meaning builder or builders, (possibly right here on VAF) suggested it as a way to avoid having rivets sitting proud because of sealant under them. This may shock some people... not all advice from other builders is good (whether it is meant well or not).
I agree it sounds like you got some conflicting info regarding the countersink depths. Maybe it was a mis-communication, maybe not. At this point I don't see how it matters in your case because you specifically said you had already C.S. deeper than what the manual specifies. Tech support does monitor activity here, and the person you talked with may have already seen your original post (though I do not know that is the case), and gave you a recommendation based on that.
BTW, I grew up right in your neighborhood. Learned to fly at KANE (North Star Aviation), and hung out at Benson airport on weekends when they were flying gliders. That was more than 30 years ago... the airport has changed a lot since then. Up late with a pounding sinus headache.... hopefully this got me tired enough that I can sleep now.....