Patrick's Sling TSi

Week 4: Rudder

This week I ran into my first significant roadblocks. I started by prepping and priming the vertical stabilizer parts. I noticed the front spar had some significant scratches. These must have come from the factory because they were circled on the reverse side. There was no indication of damage where they were circled, so I think this was their inspection process to see if the parts could still be used.

I confirmed with the factory's technical support that I could still use the parts, and they instructed me to lightly sand the scratches smooth without removing any other material. One of the other parts that gets riv-nuts installed also had a couple holes that were not the correct size. I also confirmed with technical support that the drawings were correct, so per their instructions I drilled out the additional riv-nut holes to the correct size.

After completing these fixes, I prepped and primed the vertical stabilizer frame parts. The next step was to install the riv-nuts, which is when I realized that the riv-nut tool I bought did not come with an M3 mandrel. I ordered this from Amazon on Saturday, but it was not scheduled to arrive until Wednesday and it may be even later due to a ridiculous amount of snow (at least for Oklahoma).

Since I could not continue with the vertical stabilizer I moved on to the rudder. I started prepping and priming the rudder frame parts. I also built a stand for the empennage parts I am completing. When test fitting the skin and the rudder cap, I noticed that the trailing edge of the cap seemed to be angled the wrong direction. The factory confirmed this and approved my suggested fix of filling that end with epoxy, then sanding to the correct angle.

That was a relatively easy fix, and once it was done and correctly fit into the skins I match drilled the holes and counter-sunk the ones indicated by the instructions. I spent a fair amount of time trying to get the rudder trailing edge correctly aligned with the frame. I got it as close as I could, then checked the overall alignment with a laser level after clamping the rudder control bracket to my work table. I think I have it lined up correctly, but I guess I will know for sure when I can assemble it to the vertical stabilizer.

When I was happy with the alignment, I went ahead and riveted the skin to the frame. I am not riveting the rudder cap since I still need to get a tail light and mount it to the top of the cap. I am going to go with the Aveo MiniMax Ariel with the red light and use it for a beacon. I am going to use the Aveo Ultra DayLite wingtip 3 in 1 Nav/Position/Strobes, so this should cover the anti-collision light requirement in FAR 91.205. I want the additional beacon light for additional visibility and to indicate engine start on the ground.

The kit came with 20 gauge 4 wire shielded cable for the tail light, but it looks like there was only enough for the vertical stabilizer and not the additional length need for the rudder. I should only need 2 wire cable for the beacon since I don't need to have it synchronized with anything else. It also looks like the voltage drop with 20 gauge is a little high, so I am going to order 18 gauge 2 wire cable to use for the beacon. I will have to wait until I have that to rivet the vertical stabilizer skin.

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