Title: rudder fitting
Finished the temporary installation of the elevators by installing the 2 stacks of washers that I super glued together last night. Was able to fish each side in as a unit with a pair of curved needle nose pliers. worked well, even though I couldn't see in there due to the vertical stab aft spar now being in the way. While I was at it, I made a new hinge pin for the elevator trim. The one that comes in the elevator kit is just the right length to install, but doesn't give you any extra pin length to have anything to safety, so they tell you to do it later, which might as well be now while it' right in front of my face. Safetied it based on what's depicted on the drawing, but theres no dimensional callout, so you're just left making it look like the picture. I drilled a #50 hole centered on the flange and safetied with .032 wire. I then got the rudder out of the basement and peeled the blue vinyl off. Back in the day I knew this was going to be laying around for a while and I didn't want the rivet lines to get all beat up, so I had taped over the rivet lines after riveting. Unfortunately, I had run out of blue 3M tape and finished up with a roll of masking tape I had handy. Turns out that was a big mistake. The glue on that tape had turned to tacky mush, and scrubbing it off with acetone made it even stickier. I went through about 1/2 pint of acetone and a 1/2 roll of paper towels to get that goo off. Never again. I thought when I built this I had lined up the Heim joints per print, but I remeasured because I couldn't 100% remember what I had done back then. They were off a little to what's suggested as a starting point in the build instructions so I reset them. I noticed later that here's a discrepancy in the dimensions between the print and what's recommended in the instructions. In my case the instructions turned out to be closer. I eyeballed to the center of the holes and set to to the instructions and it was nearly perfect. After the first trial fitting on the V/S I ended up only having to adjust 1 joint by 1/2 turn to get all three to a point where 3/8" brass rig pins slide in. Bonus, the gap between the rudder balance horn and the top of the V/S was a constant 5/32 along it's entire length, i.e. everything is in alignment. Unfortunately, I did run into a problem that took some experimentation to fix; When I tried to get the side to side swing called out in the instructions, The left side leading edge of the rudder was rubbing on the trailing edge skin of the V/S at about mid span vertically on the left side. Also, even though I left the rudder stops a little oversized due to people saying they're too short, turns out they were STILL too short. Anyway, back to the rubbing issue; I tried unscrewing the heim joints to move the whole rudder aft and relieve the rubbing issue, but I was having to go out enough turns to get enough relief that I was pretty close to min. thread engagement on one of the joints - the center one if I recall correctly. It would have worked and would have been within spec, but I don't like being at the end of the adjustment range on anything if I don't have to, and now is the time to deal with it. I eventually decided that since the v/s skin runs aft past the aft spar by about 1/2 inch I could file a bit off the trailing edge skin at the problem area and get clearance there without getting crazy with backing out hinge joints. Took this in 3 or 4 bites, about 1/64th at a time. reinstalled the rudder after each one to get an idea of where I was at. Ended up taking off probably about 5/64" in the problem area.blending into a shallow transition over about 10" vertically, which makes it unnoticable. It gave me a constant 1/16 gap between the two skins at full deflection, even after I cranked all 3 heim joints in 1/2 turn from where I's started. The instructions say that deflection is supposed to be 35* which is obtained with the stops set so that there's a 1 1/8" gap between the rudder skin and the aft corner of the elevators at full deflection. That sounds reasonable, but it's an awfully specific number for something that's essentially hand made. Out of curiosity, I looked in the flight test portion of the manual and it says travel is actually max 35* min 30*. I was curious, so I dropped some plumb lines, drew lines on the floor and got out the protractor. According to my rough calculations, I'm set up for 33* each way which is right in the middle of where I want to be, Sweet! I still will need to remake bigger rudder stops, but otherwise I'm pretty happy with today's efforts.


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