This afternoon I got back into the rear spars. I wanted to get these ready for priming as next weekend is a 4-day holiday and I’m hoping to get some painting done.
I disassembled both rear spars and used my hex deburring tool on all the holes I had match drilled. I used TIMMY on the hard to reach holes on the flanges. I also scuffed each part after I deburred it. Here is a shot of all the rear spar parts deburred and scuffed.
As the spar forks are mounted close to the upper rear spar flange, it is difficult to dimple the skin holes with the fork riveted onto the spar. The instructions call for all the skin holes along the length of the spar fork to be drilled to their final size and dimpled now. Fairly straight forward.
I wanted to do whatever drilling and prep work needed for the electrical wiring for the wing lights to be finished before I primed the ribs. After a bit of research, I decided that I would use flexible conduit. Vans has some instructions where to make a 3/4″ hole in the main ribs. I made a cardboard template that I used to match drill a #30 pilot hole on each of the main ribs for both wings.
The Chief Driller decided to get in on the action at this point and helped me match drill the pilot holes onto the ribs using my template. Thanks Damon!
Once all the ribs had pilot holes drilled, I set up my Unibit on my pedestal drill. Using some board underneath each rib to prevent drill chatter, I drilled out each pilot hole to 3/4″. I found by clecoing left and right pairs of the same rib number back-to-back (e.g. 711L and 711R) I could drill two ribs at once to save time. I used the tooling holes for the clecoes.
I’m also going to drill out the tooling holes for the pitot line so I can use a SafeAir kit. The kids were calling for me to go for a swim at this stage so I called it a day.
Build time 3 hours.