1098- Main Spar- p.13-3 step 4-7 & 9

Section 13: Main Spar- 7 hrs 17 mins (Main Spar 27:21, Wings 30:21, Empennage 265:24, Total 315:41)

Rivet count: 312 (Total 5,747)

It's been two weeks since my last post. I've been getting plenty of work done though.

There's 3.5 hrs of work and 188 rivets not on the video from last week. It was a busy week with work, family visiting town, hosting 8 people in our house, and a long weekend full of fun activities and a baptism to top it off. I worked a few minutes here and there getting all the holes deburred and riveting the fuel tank attach nutplates to the flanges of the main spar.

The video picks up yesterday with countersinking the fuel attach screw holes for a #8 screw dimple from the fuel tank skin.I find it odd that there is an unfinished side to the countersink, but the plans call to do it this way so the nutplate itself can be used to guide the pilot of the countersink. Many would think this is just common sense. I find it pretty neat. I also find it interesting that due to the thickness of the flanges, the #8 screw nutplates are 1100 series (CSK finish), but the #6 screw nutplates are 1000 series (flush fit). Just the little things I notice along the way... But anyways, I digress...

After the first round of CSKs are done, then we attach the access plate nut plates, and CSK those for a #6 screw dimpled skin (or access plate?!). Easy work after completing the #8 screws previously. I think I would have liked to see the plans have you make the smaller #6 CSKs before the #8 ones, but I made sure to count and recount, and verify and reverify that I was drilling into the correct spot lest I avoid a error that would cost 4 figures to fix. I shudder at that thought and am grateful to have avoided such a mistake thus far.

I also attached a small snap bushing and got the tie downs ready for install tomorrow. I skipped over the spot priming so I could do that in a well ventilated garage tomorrow, and have a fresh mind for the bucking on the tie downs. I'd say less than 90 minutes left and we will be done with chapter 13! -MS