How do you cut a square?
Posted: July 19th, 2012, 6:10 am
by 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?
Re: How do you cut a square?
Posted: July 19th, 2012, 11:18 am
by 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....
Re: How do you cut a square?
Posted: July 21st, 2012, 6:44 pm
by 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 .