Thursday, March 27, 2014

HS Rear Spar/Trim Tab Work

A lot of the project is on hold until the first coating of primer that I applied yesterday has had 48 hours to cure so I can finish the job. However, the HS Rear Spar was already fully primed and could be assembled, so I focused on that. I riveted it and its parts together per the plans in sections 8-2 and 8-3. I also added two grounding nutplates near the number 2 and 4 elevator hinges, in case I want to add static wicks in the future.

 The #2 elevator hinge bracket, with the grounding nutplate just inboard of it.
 The #4 elevator hinge bracket, mirror image of what was done to the #2 bracket above.
The #3 (center) elevator hinge, with all rivets holding the doubler in place shown here.


The other side of the HS Rear Spar, with the hinge bolts torqued properly into place.

While waiting for things to do on the HS, I turned my attention briefly to the rudder. The proseal had cured enough to move on to riveting, and I thought it would be best to rivet the trim tab trailing edge first, since if I messed that up it would be easier than redoing the whole rudder! I had the rivets alternate directions to make things more even (probably for appearance more than anything) but I think it did help it stay straight too. There are a lot of posts online that warn builders of this step, so I was going pretty cautiously... It actually turned out to be a lot of nervousness over nothing, it went together very easily thankfully!
The rudder trim tab, with the trailing edge riveted together.

I'm not sure if the picture does it justice-- looking at it now, it appears to be a little wavy, but it actually came out very straight. There is one spot near the bottom corner that we'll need to fill in slightly though, because the corner got rounded off too much on one side, but I'm pretty confident it won't be that big of a deal. I'll see if I can take a better picture of it once it's all assembled together.

Sarah found the mother load of primer across town today, and so we bought 6 more cans... hopefully that should be enough for the rest of the empennage! Now we wait until tomorrow to finish priming and then begin the final assembly of the horizontal stabilizer.