Pleating Techniques

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unknownfolder
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Pleating Techniques

Post by unknownfolder »

When I am attempting to fold a grid that is an odd number (ie 13 by 13), my folds are usually off by a few millimeters. My question is: is there a technique to make my folds dead-on accurate? I ask this since some of my folds go off by minute measurements. The last fold is always short of the paper. Therefore, my model fails before I even get the chance to give it a decent try. Help on this would be much appreciated.
Whenever I do complex Origami I get this sinking feeling.
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JeossMayhem
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Post by JeossMayhem »

First of all, folding paper actally decreases the length of the paper by small, small amounts, as you deform the paper more this will become more evident.

Secondly, your accuracy depends on your method of gridding. If you're using a special equation to find your divisions using other creases, this could be a problem, especially as your desired grid size increases. Making one small inaccuracy on your guide creases will mess all the subsequent creases up.

Thirdly, I think the best and most accurate method is to just take a ruler and a calculator and find the length of each 13th. Mark then with a pencil on each length and then just fold using those guides. This way, you know you're precise when the edge of the paper meets other marks, and you don't have to deal with extraneous creases.

Good luck.
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origamimasterjared
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Post by origamimasterjared »

Well, how do you make your 13ths? If you just start out by making 1/13 and form the rest from there, STOP. It's much harder to make straight, accurate creases if the area you're folding is long and narrow. It's much easier if you start with much bigger regions. For 13ths I find that the best way to start is by finding the point that is 5/13 from the edge. This leaves 8/13 on the other side, and 8ths are easy!

I usually use the first method on this page: http://origami.gr.jp/People/CAGE_/divide/06-e.html

Unless you're using a paper that is exactly 26 cm across or something (a multiple of the divisions you need), I find it much harder to be accurate by measuring.
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unknownfolder
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Post by unknownfolder »

Thank you for all the suggestions. I would have never thought of that technique jared. Now all I have to do is try to understand the table on the website link. I am having a little trouble understanding what the variables represent.
Whenever I do complex Origami I get this sinking feeling.
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Brimstone
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Post by Brimstone »

This is a general advice regardless of the number of pleats. DO NO go find the 1/.. th of the paper and then start folding alternating mountains and valleys. With each crease you make you introduce some error, and this method "spreads" the error.

What you need is to "contain" the error. Try instead to do the largest division and then divide those again. For example say you wanna divide in 64ths. Do not go and find the 64th part of your sheet and then alternate mountains and valleys out of it. Instead find the half of the paper. Then all the 4ths, then all the 8ths, then all the 16 ths then all the 32 ths and finally all the 64ths. This way you contain the error within the two creases of each strip instead of populating it to the whole sheet.
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Max
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Post by Max »

Try that page, and try to unterstand each of the following pages...

Now i'm into 13th too, because i found the thread about Lang's Fiddler Crab *g*

=P~
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perrosaurio
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Post by perrosaurio »

That page is really useful, I discovered it when looking for /9s. I totally agree with everybody's advice about not doing the creases from the unit one, because it propagates every small error you do on each one of them. My suggestion should be use the biggest even fraction, in this case you create 1/13 and start folding 12/13 in half and again, or, if you are using haga's theorem the 10/13 created and fold half. If you are interested I did a revision of the first Haga's theorem of that page on my blog's last entry.

Regards
perrosaurio.
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http://origamido-en.blogspot.com/
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unknownfolder
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Post by unknownfolder »

I finally divided my paper into perfect 13ths thank you for all the help.
Whenever I do complex Origami I get this sinking feeling.
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unknownfolder
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Post by unknownfolder »

Okay, I have strange question. Here it goes. Can paper lose its shape? Here is the scenario: I folded paper into 48ths (yeah I had nothing to do that day). When I finished the first part of the 48 x 48 grid, I left it sitting overnight. Whenever I start to fold I always am certain I have a perfect square of paper. Now today, I was going to start the next half. I had not creased both diagonals, only one, so I went to crease the other and for some reason it would not crease through the center. I looked at the other crease and when I reinforced it the paper was askew. Keep in mind I completely flattened the paper. Can someone explain this phenomenon?



I put this here because a new topic seemed so pointless, when this one already covered pleating
Whenever I do complex Origami I get this sinking feeling.
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Max
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Post by Max »

The paper didn't lie completely flat.
I made the same experience some time ago...
You think the paper is flat, but it isn't. When folding a bigger, precise grid, these small errors can have a big effect on your outcome.
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Post by origami_8 »

Most of the paper we usually use is machine made paper so it will expand more into one direction than into another. When precreasing a paper into a larger grid, if you need the diagonals make them first, then try to alternate the direction your making your creases at to minimize the error.
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