Rear h-stab spar assembled

Late start in the shop tonight- Josie and I went out to dinner and didn’t get home until 7:30 or so.  Once we got home, I turned on the A/C in the garage, let things cool off for a bit, and then got right to work on the rear spar.  Nothing too fancy here-the two reinforcement pieces are clamped into the spar channels, and you rivet away.  The only caveats are to make sure you skip the holes for the ribs and elevator hinges.  As recommended in the instructions, I put some blue painter’s tape over those holes to keep myself honest.

Once the reinforcements and channels were attached, the next step was to rivet on the outer elevator hinge brackets.  Finally, it was time to bolt on the center hinge bearing, which was where the only oddness of the night came.  I dutifully dug out the proper bolts, nuts, and washers. (noting to myself along the way that it was time to buy another storage bin for these things)  I went to push the first bolt through the hinge bracket-and it wouldn’t fit in the hole.  Huh?

Well, there were basically two possibilities here: either the instructions called for the wrong hole size, or I misread them and drilled the wrong hole size.  I checked back and found that the holes should have been drilled to #12.  I then compared the bolts to my trusty drill bit gauge…yep, #12 is the perfect hole size.  I don’t know what I drilled those holes with, but it wasn’t a #12 bit.  Going through my bit collection, I found that I did indeed have a #12 bit…weird.

The only remaining issue was that these holes had been match-drilled with the bracket clecoed in place.  Well, with the large holes I had drilled now, there was no way to really clamp the thing in place and match-drill again.  So I just separately drilled the holes to #12, hoping that everything would line up…and it did.  On went the bolts, nuts, and washers, and the rear spar was officially done!

I really wanted to move on to the front spar, but it was getting late as usual, and I try to knock off the air tool usage after 10 or so, especially the rivet gun.  No worries though, the front spar is a lot simpler, far fewer rivets to take care of there.

The finished product from tonight:

Rear hstab spar

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