Sunday, March 23, 2014

Horizontal Stabilizer - Day 3

Made it through almost 4 pages of the plans today! While yesterday dealt with parts going on the HS rear spar, today was all about the HS front spar. I started by making the HS-1013, HS-1014, and HS-1015 spar caps and stringers out of their raw materials:

Starting Section 8-4

The familiar process of measuring, measuring again, cutting, coarse sanding, coarse filing, and fine filing began. Sarah was away today, flying to KPRO (Perry, IA) in a Cardinal with some friends to attend a meeting with (and join) the 99's. Super excited for her, and jealous that she got to ride in a Cardinal :-)! In her absence, my friend Roy stopped over and helped keep me company with the fabrication process. The spar caps then needed to be clamped into the HS front spar and match-drilled to the specified holes. About 4 hours later (including a quick trip to Sears to buy more 3/32" drill bits), I had these parts in front of me:


At this point, we were in the middle of section 8-5, which called for the temporary assembly of the HS front spar, doubler, caps, and HS attachment brackets. I got a kick out of the fact that the plans called out to use "something flat" to align the brackets square against the spar.

The plans for temporarily assembling the HS front spar components

My "something flat" was a scrap 1"x1" piece of square metal stock, left over from when I built my C-frame dimpling tool.

It turns out that a total of nine holes are necessary to rivet these brackets to the front spar (only 4 had been drilled when the above photo was taken). Needless to say, the drilling process had my full attention! Anyway, some time later I had completed everything in this section except for the riveting portion, and was able to move on to the ribs in section 8-6 thru 8-8.

Even though Sarah was away today, I still need to give her credit on this step, since in anticipation for this section she had already unwrapped and deburred all of the HS-1004, HS-904, and HS-905 ribs a few days ago during some downtime, allowing me to blast right through an otherwise lengthy and tedious deburring task. All that still needed to be done was cut out the special parts of four of the center ribs, bend the flanges to spec, and then make some wooden cradles to hold the HS upright as it is assembled. A short while later, I had the HS skeleton clecoed together, along with the skins set in place in their cradles:

The HS skeleton, next to the R and L skins set in their new cradles.

Today ended with clecoing the skeleton to the inside of the skins. Now for the first time, we have something that looks like a horizontal stabilizer!
Last pic of the day: End of section 8-8, step 8!