Trunk Math

The good news is the trunk is fine, just the way I looked at it was off. This morning at work I walked out to the parking lot with my digital calipers in hand. I measured the gap on the right side of the trunk lid, near the front it read .196 inches and at the rear it read .151 inches. That I could see, so now I measured the let side which I thought looked good, near the front it read .165 and near the rear it read .209 inches.

Time to do some ciphering. The difference between front and back on the left is .044 and the difference between front and back on the right is .045 meaning the trunk lid sides are parallel, but it is installed crooked. If we add up the gaps at the front we get .361 while the back adds up to .360 inches. At this point we’ll go ahead and throw out that odd thousandth of an inch because of not measuring in exactly the same spots on each side. The gap between trunk and fender should be .180 inches all around. I guess tomorrow morning I’ll go out to the garage and loosen the 4 mounting bolts and see if I can it all lined up.

For fans of higher math let’s use a little trigonometry and see what the angle of error is on the freshly painted trunk lid. The error between front to back was .044 inches or the opposite side of our triangle. The distance between front back measurement locations is 22 inches or the adjacent side of our triangle. Using my favorite mnemonic, Oscar Had A Hairy Old Ass, I know the tangent of the angle is the Opposite divided by the Adjacent. I can divide .044 by 22 and get .002, now I just have to figure out what angle has a tangent of .002, or what is the arctangent of .002. The calculator that comes with windows does tangents, but not arctangents, so a googling I go. I am led to Carbide Depot.com and their free online trig calculator which gives me an angle of 0.11459140° or if you like, 0° 6′ 53”.

Not much of an angle, but noticeable (at least on one side) to me.