1098.1- Main Spar- p.13-3 step 8 & p.13-5 step 1

Section 13: Main Spar- 5 hrs 26 mins (Main Spar 30:17, Wings 34:30, Empennage 266:39, Total 321:07)

Rivet count: 20* (Total 5,767)

Lucky Chapter 13 is complete!! The numbers from my build log tracker tell me I worked 11 sessions averaging 2:45. Not too bad. It took about 7 weeks of actual building to do that. Now for the bad news. Unfortunately there was a two year break in the middle as discussed previously. So in reality, I averaged about 16 mins per week, or 2.5 minutes per calendar day. OK, now that I have entertained myself sufficiently...

The day started off well enough. I set up the spars for self-etching primer along the flanges (pic 1). I had been delaying that for a few days since it had been raining and humid, and I needed a well-ventilated garage. While I waited for the one side to dry before flipping over the other flange, I took care of some admin by annotating the parts I had "pulled" off of my inventory sheet. In the process of doing so, I realized I had not updated the empennage kit inventory the entire year I was in Mississippi. Good thing I had some time on my hands for that. After I flipped the spars and primed the other side and all the dings the main spar got in random spots, I started looking ahead to the next section for the wing ribs and I pulled those parts from inventory.

The primer will take 24 hours to fully set, but can be touched and handled after about 1 hour. All that remained was to rivet the AEX tie downs to the spars and prep the 823PP brackets and bolt them to the spars/AEX tie downs. I was on my last bolt for the night, and I have no clue what got into me, but I completely spaced on how tight I was turning the wrench and ended up collapsing one of the platenuts and shearing it (pic 3). Of course it happened on the last bolt!

So I removed the rest of the bolts, but the over-torqued one would not come out. After thirty minutes of trying everything I could think of, I busted out the #40 drill and went to work on the plate nut and the bolt together. I drilled through, rotated the bolt a 1/8 turn, and drilled again. I essentially cut the bolt in two with a drillbit. Not pretty by any means. Then I continued use of the drill by drilling out the ten rivets holding the AEX to the spar, so I could access the two rivets holding the now-split plate nut (pic 4). Then I re-riveted the plate nut to the AEX, and the AEX to the spar. So 32 rivets today, but only 20 of them count.

Mercifully, the second time around went better than the first, and after some bolt markings, chapter 13 is in the books (pic 2). I only have four days left of building before I have to take a two-month break for work, so I will work ahead with the ribs, and skip over anywhere that directs priming until January when I can order a fresh batch of AkZO. I don't expect to get very far this week, and I will likely spend most of my time fluting the ribs and deburring edges to be honest. So stay tuned for more updates! -M

 

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