Brmorgan
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OK, so we have the "what have you built..." thread, so how 'bout one to share little construction tips and shortcuts and whatnot. And it could be anything - building stuff WITH your milled wood, building stuff to mill with, whatever. I'll start off by sharing two ways to mark a perfectly square right angle if you don't have a square handy for whatever reason, or the one you have is far too small for what you need to lay out. The first still requires some math or method of measurement, and is one many of you will know, and uses a Pythagorean triangle:
Using Pythagoras' theorem, in a right angle triangle, the the lengths of the sides are a²+b²=c², as most of you should still remember from high school math! Thus, if you draw a triangle with short sides of 3 and 4 units and a hypotenuse of 5 units, it will form a right-angle triangle every time. 3² (9) + 4² (16) = 25; the square root of 25 is 5. This will work on any scale, use inches, feet, yards, miles... It will always form a right angle.
Another method is more crude, but if you are, say, trapped on a desert island and lack ANY sort of scaled measuring device, this is for you!
If you draw two circles with their centers on the same line, a line drawn through the two points at which their circumferences intersect will always form a right angle to the first line. The circles don't even need to be the same diameter, just centered on the same axis. This is the method the Egyptians purportedly used to lay out the Pyramids.
Using Pythagoras' theorem, in a right angle triangle, the the lengths of the sides are a²+b²=c², as most of you should still remember from high school math! Thus, if you draw a triangle with short sides of 3 and 4 units and a hypotenuse of 5 units, it will form a right-angle triangle every time. 3² (9) + 4² (16) = 25; the square root of 25 is 5. This will work on any scale, use inches, feet, yards, miles... It will always form a right angle.
Another method is more crude, but if you are, say, trapped on a desert island and lack ANY sort of scaled measuring device, this is for you!
If you draw two circles with their centers on the same line, a line drawn through the two points at which their circumferences intersect will always form a right angle to the first line. The circles don't even need to be the same diameter, just centered on the same axis. This is the method the Egyptians purportedly used to lay out the Pyramids.
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