Static System Leaks

I finally got to the point where I wanted to get an IFR certification done for my RV7 and took it to a local avionics shop. Everything was great. They took my altimeter up to 30k and it did fine. Transponder checked out fine. Everything was great ... except ... right -at- my static ports there was a leak. They have worked to seal that leak and are having no luck. I'm reaching out to the collected wisdom on the forum here for suggestions.

I am using the standard Van's pop rivet static ports. We have tried RTVing the tubing to the stem of the pop rivet, and it seals fine on the inside of the fuselage skin but leaks under the -head- of the rivet on the outside of the skin.

I believe I have heard people say they have nested smaller tubing inside the larger tubing to get a better fit on the shank of the pop rivet, but am having trouble finding any reference to that. I have read the following thread :

http://www.vansairforce.com/community/showthread.php?t=36191&highlight=pop+rivet+static+port+sealing

It is good information but we are somehow not quite getting a successful outcome. Any additional information would be welcome. The avionics shop does have an experienced RV builder who helps them part-time and he is being consulted about what -he- did, so maybe we'll have an answer soon anyway. But in case someone had meaningful insights I wanted to float the question. Thanks!

I have better luck taping off the static ports and then tapping into the system somewhere else to check it, that way you are not fighting that problem (the skin to port seal is not part of the static system).

What Walt, said.

I did something a little different. I took the safe air ports, cut down the external part in a lathe, drilled the port hole to the rivet size and installed sealed the safe air, rivet and head with pro seal and pulled the rivet to hold the modified safe-air in place. That way I have the threads inside for the connection.

Pro-seal oozed out under the rivet head, so I know it is sealed everywhere.

Hey Dwight, Noel here...yes, the shop called me this afternoon. I will be there early tomorrow am to see what they are talking about...did not make sense to me from the phone conversation.

I am in the midst of moving my advanced dimentia father-in-law from independent living to assisted living and can not spend a lot of time this week at the shop. I will look at your plane in the morning, and I have a number of different static port fittings and tubing solutions. Do you want to be a part of this work, or are you looking for the shop to just fix it?

Taking this to email to not spam the group with one-on-one planning communications. Thanks for the input, folks!