[koda2]

There have been a couple of posts about rivet technique lately.

I don't know if this video has ever been mentioned before; I couldn't find it on a search. This is an old video on flush riveting but extremely well made. I suspect the principles are still the same.

http://www.youtube.com/watch?v=IagmAgHvcWQ

It mentions 110 degree countersinks. I have never seen or found such critters made for aircraft use.

The old Naval Aeronautics manual on rivets also mentions a 110 degree inner sheet countersink and a maximum inner countersunk diameter of .200 - .208 for AN426AD-3-x rivets. My dimple dies (Avery springback dies) produce a dimple that will often sit proud of such a countersink diameter despite trying to preset them and I have had to make some countersinks bigger in order to get the two sheets to lay completely flat. Any tips?

Vans assembly manual also recommends dimpling skins of .040 or less but I have seen different recommendations elsewhere. Anybody have any data to support certain techniques?

Dave A.
RV-6AQB

 

[Top_prop]

Great post!

I'm still in the newbe camp, but was told somewhere to counter sink just a hair deeper than flush inorder to compensate for the tendancy of a dimpled piece above to nest a bit high and to compensate for the little bit of primer that I put on my parts prior to riveting... I think that is the common way of compensating for the 100deg vs 110deg problem the video brings up...

Tom