September 28, 2018

Fabricating R-918 attach strips, match drilling rudder trailing edge, match drilling rudder skins to skeleton

The last step before clecoing the skin is to fabricate the two R-918 strips, which will eventually attach the bottom fiberglass fairing onto the rudder. The remaining material on that same long strip of aluminum used to fabricate the shim just so happens to be the perfect length to produce the two 1 1/8"x18" strips called for by the plans (crazy, it's almost as if Van's planned this!). Cutting the strips apart then finishing the corners and edges with the Scotchbrite wheel went well. The strips were then clamped to the bottom rib to be match drilled.


I clecoed on the skins and reamed the appropriate holes to #40. I couldn't resist propping it back up and admiring my new rudder. As a tailwheel instructor, it's hard to overstate the importance of this particular control surface.


There is an eeeeeeever so slight wave in the trailing edge, but it's not huge (only around 1/16" at most). I'd have a problem if there was a lot more waviness here, but this amount is merely cosmetic from what I can tell. It probably won't be noticeable at a distance.


The trailing edge should be drilled square to the rudder since the rivet shanks will be also be square with it. I set the rudder on some 2x4s on my workbench and used a level to check that everything was indeed level.


I managed to improvise by attaching a small level to my drill to make sure the drill bit stayed square to the rudder.

It looks stupid, but it works.