Day 15

Countersinking Main wing spars. Wow. That was a lot of rivet holes. We spent some good time trying to find a way to streamline the process.

First, we tried using a hand drill with the spar sideways up on the table. This worked fine, other than it required quite a bit of effort drilling from thins angle, as well as having to apply opposite pressure with your other hand to keep the spar from moving.

Second, we attempted using a small drill press, which took a little alteration to get the spar to fit. After trying the first hole we discovered that without securing the press to the table, it would just press up as we tried to drill down. It also took quite a bit of time to move the spar and line of the hole after each one.

Third, we moved the spar down onto the ground where we could drill in that direction rather than sideways. This required far less energy to perform. It was working great until we realized we had the wrong sized bit in the drill after approximately 50 holes or so. We put the correct bit in place, set the proper depth again, and proceeded. This time only to discover that after three holes, they started to look smaller… Metal shavings would stick to the bottom of the plunger guide as we drilled. So it came down to a somewhat tedious task of drilling, clearing the shavings from the spar, then the bit guid, and drilling the hole a second time to make sure it was correct.

We did however get into a pretty good rhythm. We we able to get it down to an average of 16 seconds a hole. (We timed ourselves…) Once completed the spars looked great. Greatly looking forward to starting their assembly.