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Final drilled rudder
skins to rudder skeleton. Disassembled rudder and deburred
rudder skins.
One challenge I had to
figure out is how to machine countersink the rudder trailing edge
(R-916 a.k.a the AEX wedge). There is about a 8 degree taper
to the trailing edge and looking at web sites of other builders,
they machine countersinked the AEX wedge with the countersink running
perpendicular to the skin holes. In other words, I need to
figure out how to countersink this thing with the sides perfectly
flat with the countersink cutter perpendicular. Tami actually
came up with the design (jig) to accomplish this. We started by angle sanding
a 1" x 3" wood using a Dremel belt sander that I purchased
when Tami was doing wood crafts.
Tami was able to roughly
sand the angle into the scrap piece of 1" x 3" wood.
When Tami got it roughed in, I took a wood chisel and "fine"
chiseled the angle I needed in the 1" x 3" by taking out
a sliver or wood, setting the rudder trailing edge in the angle
and doing it all over again and again until I got this thing to
lay flat in the scrap wood.
As you can see, the
rudder trailing edge (R-916) lays flush in the "wood jig".
I then clamped it to the drill press and drilled a #40 pilot hole
into the wood jig so that the countersink alignment pin cutter had
a place to go.
Once I got the countersink properly
adjusted to allow the rivets to sit roughly flush, the simple little
jig made some really nice countersink holes in the rudder trailing
edge. Care had to be taken not to over countersink these holes
as the piece is not really all that thick and it is countersunk
on both sides so that the rudder's trailing edge will be very thin.
Over countersinking would result in enlarging the hole as it would
cut completely through the trailing edge piece. |