squaring tricks.

[Dino Makropoulos]

Hi Guys.
I know that is a simple formula to test the squareness of any orthogonal triangle. (what we call, a square)
But I don't remember the equation. :confused:

Any other tricks to test the square without the help of a ruler?

I have one trick here but I like to learn few more. .

Thanks for your help.



YCF

[Roy Wall]

I always cc a board, take the off cut and flip it.....then test the match...
any error is doubled.....


Good for table to blade (perpindicular) or miter guage/sled to blade...

[Bruce Shiverdecker]

If you measure down one side 3" and 4" down the other side, the distance between the 3" point and the 4" point should be exactly 5". Then you have 90 degrees at the peak.

Bruce

[Richard Blaine]

Another test is to measure both diagonals. Assuming opposite sides are equal, measure corner 1 & 3 and 2 & 4. If both measurements are the same, then you are in square.


1----------------2
|.......................<SPACE(10)>|
|.......................<SPACE(10)>|
|.......................<SPACE(10)>|
|.......................<SPACE(10)>|
|.......................<SPACE(10)>|
|.......................<SPACE(10)>|
4----------------3

[John Lucas]

Easiest way to test shop squares is to draw a very fine line with square then flip square and draw another fine line at same starting point. If lines match, you have a square. I do that with Home Depot framing squares. I take 3 or 4 and go to the wallboard aea, draw line on the wallboard. I will usually fine one square square.
Mostly for the shop I use engineers squares of heavy steel. The speed squares also can be square and if they are, are often more handy thaan the regular squares.

[Gerry Rhodes]

Pythagorean Theorem<O:p</O:p

a<SUP>2</SUP> + b<SUP>2</SUP> = c<SUP>2</SUP> where c is the hypotenuse while a and b are the sides of the triangle

It's why the 3, 4, 5 works. 3<SUP>2</SUP> + 4<SUP>2</SUP> = 5<SUP>2</SUP> (9 + 16 = 25)

[john looser]

for larger areas ,a 6,8,10 also works.:)

[Jason Tuinstra]

Pythagorean Theorem<O:p</O:p

a<SUP>2</SUP> + b<SUP>2</SUP> = c<SUP>2</SUP> where c is the hypotenuse while a and b are the sides of the triangle

It's why the 3, 4, 5 works. 3<SUP>2</SUP> + 4<SUP>2</SUP> = 5<SUP>2</SUP> (9 + 16 = 25)

Yea, what Gerry said :p :D

[Jeff Sudmeier]

Any multipe of 3, 4 5 works and it works in any measurment :) Inches, quarters of inches, feet, etc. Course the bigger you get, the better.

We tend to use the biggest multiple we can :)

[Dino Makropoulos]

I test all above theories and tricks and they all worked fine.
Some times the simple solutions and proven ways are better than trying to reinvent the wheel. ;)
The easiest was the John Lukas way.
Then I use the P theoria.(theorum) , Richard's and Roy's tricks.
All dead on.
Thanks guys.

YCF Dino