Precreasing fractions!

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Precreasing fractions!

Hey all! I was wondering if anyone can point me in the direction (or if someone knows how then can you please show me) of a site that shows how to precrease into 16th's? Boxpleating of any sort are one of my worst nightmares! Oh and also while we are on the subject can someone also help me with 40th's? I tried a couple of times and each time only succeeding in either doing to many creases or not enough! So if anyone can help that would be greatly appreciated!

FunkeeFolder

FunkeeFolder
Junior Member

Posts: 61
Joined: June 7th, 2005, 6:19 pm
Location: USA, Texas

????
16ths should be easy:
1. Fold in half.
2. Fold halves in half (4ths).
3. Fold 4ths in half (8ths).
4. Fold 8ths in half (16ths).

40ths are a little more challenging:
1. Fold into 5ths. (You'll need to look that one up.)
2. Fold 5ths in half (10ths).
3. Fold 10ths in half (20ths).
4. Fold 20ths in half (40ths).

You should be seeing a pattern here now. If not, it's time to review prime numbers.

Joseph Wu
Senior Member

Posts: 443
Joined: April 18th, 2005, 7:27 pm

A word of advice from someone who's seen some nice box pleating models ruined due to terrible divisions:

Do not go and find the 1/16 th and then go mountain valley mountain... like an accordion, this will only "propagate" the error. Instead do as Joseph said and find the 1/2, 1/4, 1/8 each time and then divide those again in half, this way you "contain" the error you introduce each time with every crease you make.

Brimstone
Buddha

Posts: 1704
Joined: November 23rd, 2004, 3:59 am
Location: Colombia, South America

I think my major problem was as Brimstone said
Do not go and find the 1/16 th and then go mountain valley mountain... like an accordion, this will only "propagate" the error.

I did exaxtly that and it came out weird so I confused myself into thinking I did the whole thing wrong when it was a simple as that! (Sleep I need SLEEP!)

Thank you Joseph and Brimstone! If that was a snake it would of bit me!

FunkeeFolder (who's stupidity even amazes himself)

FunkeeFolder
Junior Member

Posts: 61
Joined: June 7th, 2005, 6:19 pm
Location: USA, Texas

Ive know a method of splitting into 3rds and 5ths which Ive never seen in any book yet Im sure it exists as it is very simple and works perfectly with no mess besides a few tiny pinches along the sides.

OK You have a square.

1. Fold the paper approximately 1/3 and make a tiny pinch. (It does not matter how far off you are.)
2. Fold the other edge of paper to the pinch made in step 1 and make another tiny pinch.
3. Fold the original edge over to the pinch made in step 2 make a tiny pinch.
4. Fold the other edge back to the crease made in step 3 ( make tiny pinch)
5. Keep going back and forth with edges and eventually you will find that the crease you are making is one that you already have. This is exactly 1/3 so crease this fully. Then fold the other edge to this crease.

IT usually only takes 1 or 2 cycles to find an exact third. I had the mathst of this method showed to me at one stage it is quite simple and u can see with every fold it gets closer to 0.33333333.

1/5 works in the same way but is slightly more creases. I can explain it if any one wants....

thanks

T
Junior Member

Posts: 119
Joined: October 9th, 2004, 12:02 pm

T wrote:1/5 works in the same way but is slightly more creases. I can explain it if any one wants....

This method was described by Thoki Yenn on his site:

origami_8