Back to work on the h-stab

So here I am, freshly back from my first-ever (and certainly not last) trip up to Oshkosh, and it’s definitely time to get back to work.  A short confession before we get started here: some of the work described herein was done almost two weeks ago, but I didn’t do a post then mostly because I spent about 15 minutes in the garage and when I stopped, I was quite furious.

Anyways…when we left off before, all the h-stab skeleton prep was done and it was time to start skinning.  The first step in the instructions is to rivet the HS-707 nose rib to the top side of the skin.  That seemed straightforward at first: cleco in place, looks good, start riveting.  I started from the trailing edge end and moved forward, which in retrospect may have been a bad decision.  I had no problem keeping the skin pulled against the rib until I got to that last rivet on the leading edge.  Here, the skin is pulled into a more noticeable bend to sit against the rib, and without the cleco in place, the skin sat a good 1/2″ or so from the rib.  After some thinking, I clecoed the HS-708 rib to the HS-707 rib and clecoed both to the bottom side of the skin.  This pulled the skin tight against the rib, but also made for some tight quarters.  A little experimentation, and I had the bucking bar in place…I fired the rivet gun…crap, the shop head is clinching.  Drill-out time!

Ever mindful of the opportunity to damage my nice skin, I drilled carefully, popped the manufactured head off, and started trying to drive the shop head off.  Boy was it stubborn…and when I finally got it off, I realized my error of judgment.  With nothing to brace the rib flange, it had bent itself pretty severely.  Oh, and despite being careful, I’d enlarged the skin hole.  I expressed my frustration in some terms which shall not be repeated here, stomped out of the garage, and found something else to occupy me for the rest of the night.  That ended up being the last time I was in the garage pre-OSH as well, what with trip prep.

So tonight, I resolved to get past that pesky thing and move forward.  One important step here was to swallow my pride and get help.  I drove all the previous rivets solo, awkwardly holding the bucking bar and gun at arm’s length.  Which is kind of dumb when you have a lady around who’s expressed plenty of interest in helping.  So yeah, I took advantage of her services tonight.

After careful consideration, I decided that there still wasn’t any better way to pull the skin flush than to cleco the bottom side to the nose and main ribs, so I did that.  I then recruited my help to hold the bucking bar while I drove my first-ever “oops” rivet.  All in all, it was less stressful than I’d built it up to be.  Next, I clecoed the tip rib in place, and set about riveting the bottom side of the skin to HS-707.  Again, here having a helper was, well, helpful.  We got those rivet shot in no time.

Next step is to cleco the front spar in place and blind rivet HS-707 and -708 to the spar.  Seems easy, but oh wait…the only rivet puller I have is a cheapo unit from Lowes or something, and the head is huge.  No way to use it in the tight confines of the stab that I can see.  So I stopped for the night, and tomorrow I’ll see about finding a rivet puller that fits in tight spaces better.

(no pictures tonight, I’m afraid…)

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