More H-stab spar work

Another short session tonight.  I seem to keep finding things I need before I can do certain steps.  Last time, I stopped when I got to a step requiring a drill bit size I wasn’t sure I had.  A large portion of my tool set was bought secondhand as a unit, and it included a lot of assorted drill bits.  I’m pretty sure there’s probably a #21 in there, along with the other sizes I need, but I’m not sure what sizes I have.  I needed to order some stuff from Spruce anyway, so I tacked on a drill bit size gauge.  I could work out the bit sizes, since I have a set of analog calipers, but I’m not sure I trust myself there.  I’d rather wait and make really sure I’m right before possibly ruining parts…

Anyway, my order from Spruce didn’t come today, so I decided to skip ahead a bit.  Next step was to attach and match-drill the outboard elevator hinge points. (HS-412PP and HS-413PP)  These were pretty straightforward, though the inboard pieces were a little trickier since each hinge half has only two rivet holes.  Normally you cleco half the holes between two pieces to hold them together while match-drilling the other holes, then switch and repeat.  But with only two holes, only one can be clecoed while drilling, which doesn’t exactly lend itself to stability.  So I clecoed both holes, added a clamp, then individually removed the clecos and match-drilled.

Next up was the center hinge point, HS-411PP, and the VA-146 bearing.  Only one of the HS-411 halves is pre-drilled, so the halves have to be clamped together over the VA-146, then clecoed to the spar assembly, and then all three pieces are drilled through.  I fussed over this probably more than I needed to, but I was acutely aware that this was a good opportunity to ruin my first part.  But all turned out well; once drilling was done, I deburred everything, cleaned up, and riveted the assembly together.  First rivets on the project are done!

Next, I moved on the front spar.  I got as far as clecoing the inboard holes for the HS-410 and HS-414 reinforcements, but the next step involved tapering the ends of the reinforcements…oh, guess what, I don’t really have anything good to do that.  I went ahead and laid out the taper patterns, but decided to wait until I had picked up a belt sander to do the tapering.  I could have possibly skipped forward to other steps, but I’m getting a bit uncomfortable with having several items I need to go back and address, so I elected to wait.  I’m going to grab the sander on the way home from work tomorrow, and my Spruce order should come in as well, so I’ll be able to go back and finish the drilling jobs I skipped.  Assuming, that is, I have the necessary bits…

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