How do you cut a square?

[zxop9]

from printer paper it's easy, but from some arbitrarily shaped sheet of methyl cellulose treated tissue paper i have no idea. I have tried many different approaches using rulers, protractors, and compasses, but i always end up with a noticeable trapezoid (after i start pre-creasing). I don't own any expensive equipment; just a razor blade, pencils, and the three other instruments i mentioned earlier. So to conclude: how do you origami artists cut a perfect square?

[roodborst]

It might be hard to explain, but I'll try.
I use this to make squares out of a big 70cm x 50xcm sheet of tissue foil. I end up with 6 pieces of 30cm x 30cm. Or I make 2 big ones and some smaller ones. It ain't perfect but it works for me.
/-----/ = paper
,,,,, = empty space

Starting with a rectangle
/------------------------/
/------------------------/
/------------------------/
/------------------------/
/------------------------/


Fold bottom left corner diagonal 45 degrees
/----------------------/
,,,/-------------------/
,,,,,/-----------------/
,,,,,,,/---------------/
,,,,,,,,,/-------------/

Fold top left corner diagonal 45 degrees
,,,,,,,,/--------------/
,,,,,/-----------------/
/----------------------/
,,,,,/-----------------/
,,,,,,,/--------------/

Now cut paper on the dotted line, Going through all the layers
,,,,,,,,/.--------------/
,,,,,/---.--------------/
/--------.--------------/
,,,,,/---.--------------/
,,,,,,,,/.-------------/


You now have this:
Folded triangle+++++Left over paper

,,,,,,,,//,,,,,,,,,,,,,,,/--------------/
,,,,,/---/,,,,,,,,,,,,,,,/--------------/
/--------/,,,,,,,,,,,,,,,/--------------/
,,,,,/---/,,,,,,,,,,,,,,,/--------------/
,,,,,,,,//,,,,,,,,,,,,,,,/-------------/


Unfold the triangle you've just cut, and now you got a square that has the diagonals precreased. You can use the same technique on the left over paper (starting at the lower right corner) to make some more squares.
I find this to be the fastest way to make squares without measuring or using a rulor. It might not be as neat but it alot faster!

Another good way is to make (or buy) a perfect square piece of (sheet)metal, You can lay it on top of your paper and use a razor to cut a square (Don't use your kitchentable for this!). The downside is that all of your squares are the same size. Using the technique above, you get to decide what size you want.

Hope this made any sense! Using -/, to draw is kinda hard....

[roodborst]

Damn.. for some reason when I post the text all of the /-. get shoved to start of the sentence.
Edit: Instead of using 'space' I put a , hope it is still clear enough

[FlareglooM]

Use Alt-255 as a blank space, then it should work.

           Yay

And maybe for the edge use | (Shift+BackslashButton, for me it's above "ENTER")

This can help:
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And this link: http://www.youtube.com/watch?v=xdI0Sq-19cE

[origami_8]

I use stencils, a cutting mat, a sharp knife and a metal ruler. Some years ago I let the stencils cut from the cheapest wood at a hardware store. They were cut with a big machine and are very accurate. I also have some steel stencils from a big order that was placed by a bigger group of folders who paid for them beforehand and got the stencils handed out at a convention.

[Baltorigamist]

There's a technique I use that seems to work pretty well.

1. Make an arbitrary crease across the entire sheet, about the same distance from the opposite edge as the size square you want.
2. Make another crease perpendicular to the first one; this is also extended across the sheet.
3. Bisect the resulting right angle, again across the entire sheet.
4. Make a second perpendicular crease (parallel to the one from 2) on the opposite side that goes until it hits the bisector.
5. From that point, crease perpendicular to the fold from 2.

It's kinda hard to explain in words (isn't all of origami), but I use it all the time.
Besides that, I just check for right angles and measure.

[zxop9]

Awsome thanks a lot for the responses I will try some of these techniques thank you

[gordigami]

This topic has been explored several times in this forum. I suggest searching under other topic names, such as slide cutters and such.
A really good, accurate slide cutter will be expensive, ( about $ 300 and up), but well worth it, and will probably last for decades .
Faye Goldman has a class on cutters , oftentimes at OUSA conventions .
Ultimately, cutting an accurate square, while quite basic, may be the most difficult procedure in origami .
Well worth your time to master the procedure sooner, rather than later .
For the record, I use a Rotatrim Professional 18 inch cutter, slightly modified for accuracy .

http://www.amazon.com/Rotatrim-RC-RCM18 ... B0002TKH34

I also use a 36" contractor's " L " square , preferably from a company which makes architectual blueprinting products .

[zxop9]

that would be awesome to own, however, my financial situation won't allow for that expense until i graduate, but i will look into it regardless thank you