Print
Hits: 4315

This week I finished bonding the reinforcing strips behind the flanges on the empennage tips, and drilled out all the holes to 1/8 inch. Then I realized that the edges of the rudder and elevator skins refused to sit down nicely against the empennage tips. I noted that the flanges were not at the same angle as the skins. The flanges were splayed out a bit, so they rested on the skin only on the very edge of the flange.

Sanding block clamped to edge of tableI decided to remove a bit of material from the edges of the flanges to make the flange surfaces more closely match the skins. The reinforcing strips and thickened resin that held them in place should provide enough extra strength so that it is safe to remove that material from the edges of the flanges. I messed around trying to sand the flanges by hand, but it took too much care to hold the sanding block at the just the right angle, and to be sure to only sand the flange. I was making very, very slow progress. I finally woke up and clamped a long sanding block to the edge of my work table, so it was at 90 degrees to the table top, and at the right height so only the flanges would be sanded. Then it was a quick job to hold the tips against the sanding block and true them out.

I had to put in four rivets in the outboard elevator ribs - I couldn't figure out how to get at them when I riveted the elevators years ago, and I wasn't brave enough to try some of the ways that other builders had used. Today I tried using a back rivet plate, a thin steel bar laid on top of the rivet tail and a hammer to bash the bar, but I couldn't get the rivet to set no matter how hard I swung the hammer. So, I used the same setup, but I placed a rivet gun with flush rivet set on the steel bar, and managed to set each rivet with a long hard blast of the gun. Three of the four rivets came out looking good, but one of the ones on the bottom of one elevator is sitting a big proud of the skin. I don't know what I did to have such good luck - usually my screw-ups end up on the upper surfaces where everyone can see them.

I put the vertical stab and rudder tips on their respective surfaces at the same time, and was dismayed to note that the VS tip sticks up noticeably higher than the rudder tip. I thought I was finished with the filler on those tips, but that was obviously just a pipe dream. I'll have to reinstall the elevators so I can see if I have a similar issue with them.