It turns out that I have a total of six bolts holding the bottom plate of the mirror cell to the attachment brackets -- and the bolt, lock washer, and nut combo weighs 0.4 ounces. Strictly speaking, six bolts are not required. Each one has the tensile strength to easily hold this, and I am not worried about any of them working loose. In addition, I can also remove the extra material on the attachment bracket where the second hole was located, perhaps saving two ounces total.
UPDATE: When I was looking for an alternative to turning down the bottom plate of the mirror cell, I did a little thinking about alternative strategies. One is to cut the circle to a hexagon, which can be done by drawing a circle of the required diameter, measuring 60 degree angles, then drawing lines connecting the points, and running these through a bandsaw. In addition, the area of a hexagon that fills radius r is 3r2, instead of pi * r2, so slightly less weight. A triangle is another possible strategy, where the area of radius r is 2r2, so even more weight reduction.
You might also see if a bolt + nylon lock nut is lighter than bolt + lock washer + nut; I think it should be.
ReplyDeleteThe difference will be small, but adds up...