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Completing the Rudder

Hours: 4.5 Manual Ref: Page 7-11 steps 1 through 6; Page 7-12 steps 1 through 5 Partner: N/A

After having read about all the fuss over curved trailing edges, I spent a great deal of effort ensuring that the edge stayed as straight as possible.  Like several other builders, I also alternated the shop heads of the rivets on each side of the rudder.  The plans also state to back rivet the rivet about 1/2 way, starting vertical then rotating to perpendicular to the skin.  Afterwards I went back with the mushroom set and flatened out the shop heads, so that no part of the rivet protruded proud of the skin.  In the end, the trailing edge is as straight as the best straight edge ruler I have.  It doesn’t get much better than that! I also recorded a time-lapse video of this process.

Rolling the leading edge proved to be a bit harder than the riveting of the trailing edge.  The short section near the top was easy enough, but that middle section was quite difficult.  Thankfully I’ve been working out, because the twisting of the broom handle took every bit of strength I had.  Once I got the clecos in, things started getting a little easier.  The next hard part was having to final drill the holes with the #30 bit, then deburring.  Once the skin was bent into a curve, getting the burring tool in there was a challenge.  To finish up, the pop rivets went in with no problems at all.

Installing the lead counterbalance weight was quite the interesting process.  There was a lot of “bend the skin this way”, and “bend the skin that way” going on.  The plans said to use a #8 screw as the temporary holder of the lead weight to the rib flange.  I opted to use a couple 5/32 clecos.  The only part that I didn’t completely understand how to do was the dimpling of the holes put in the skin to hold the weight in place.  The holes are drilled to #19 in size, and I don’t have a “#19 dimple die”.  I used my 1/8 dimple die set and the machine countersunk holes in the weight to complete the dimple using the head of the #8 screw that holds it all in place.  All in all, it seemed to come out right in the end.  Now I have a completed rudder!