Ran a #40 through all the spar flange holes that had not already been match drilled. Then dialed in a #40 pilot countersink and began CSK’ing all of the nutplate rivet attach holes. This took a couple of nights to get done as there’s a huge number of CSKs that have to be made—I thought this task would never end. After the CSKs were done, I went back and dabbed a blob of Sanchem into each CSK with a small paint brush (the kind you would paint water colors or a model airplane with) for corrosion protection. Figured if the Sanchem worked (I wasn’t doing any of the prep steps like I normally would) them maybe I wouldn’t prime the holes as called for in the plans. The Sanchem worked just fine.
