Question for Spike

hugo · Post by **hugo** » Wed Mar 08, 2006 9:05 am

Hi,

I visited your website and noticed that you are dimpling the lower flange and countersinking the upper flange of the elevator spars. Why are you doing that ? Is this because you are going to use pop-rivets on the lower flange ? (I am also busy with the elevators )

Kind regards.

hugo

Post by **Spike** » Wed Mar 08, 2006 11:11 am

I moved this over to the RV-9 forum since its more applicable to the 9's.

It appears that my builder's log is probably a bit unclear Hugo. The main elevator spars themselves are dimpled top and bottom. The trim tab spar that goes in the trailing edge of the left elevator is dimpled on the bottom and countersunk on the top. That is because the trim tab hinge rivets to the bottom of the top flange of that spar. So, in order to keep from dimpling the hinge, the top flange is countersunk to accept the dimples in the elevator skin.

Does that make it clearer?

-- John

hugo · Post by **hugo** » Wed Mar 08, 2006 4:07 pm

Absolutely !

Thank you.

hugo

jim_geo · Post by **jim_geo** » Wed Mar 08, 2006 10:24 pm

You're also going to find that you do the same thing for the flap hinges as you did for the trim tab hinge. I'm sure there are other examples also I just haven't run across them yet.