We got a new Fake (pre-lit, three piece, quick assembling!) X-mas tree this year. When the time came to place the star on top, I discovered there was no mathematical way possible to make it stay put up top.

So I grabbed the calipers and a sheet of paper:

What followed was a 20 minute head scratcher where I tried to remember geometry lessons I haven’t used in 25 years. (see that ‘SOA CAH TOA’ up there? Sine = Opposite over Adjacent, Cosine = Adjacent over Hypotenuse, Tangent = Opposite over Adjacent) So i did the math, pressed the buttons on the calculator and came up with 75 degrees. All the while, my mind was thinking ‘is that in degrees? Do I have to worry about Pi?

Setting up the compound on the lathe to 75 degrees, it ‘looked’ right. So I guess I did the math right.

Here’s the result, It’s rare when a problem and my skillset overlaps so closely.

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Tags: aluminum, lathe, trig, trigonometry