The Origami Forum

im reading origami design secrets, and i'm trying to really get a solid grasp on all the concepts. i'm still in the beginning, and i'm stuck on pages 68-71 in the 2nd edition. i first tried to fold offset diagonals and verticals and follow the normal sequence for a bird base, but that didn't work... so obviously i tried to preceease and collapse, but in my inexperience could not find references enough to make all the creases. ive only been folding about three months, but i want to delve into design as soon as possible. thanks for your help

There's not much I can help you with; as Lang says, you need to shift all the other points. Don't expect the layers and edges to line up, and just keep going by trial and error.

thanks

the question is, though, if there's only one point in the center of the base patern from the diagonals and vertical/ horizontal creases, is that enough reference to fold the entire off center base? or is some type of measuring and marking required?

update: i can fold DISTORTED bases easily, but still having trouble with offset

One point should be enough. fold the horizontal/vertical creases first (perpendicular to the edges of the paper), then bisect those for the diagonals.

thanks again

the problem i'm having with that, unless i'm misunderstanding, is one flap is not in the corner of the paper, and the other points of the other 3 flaps are "off the page." if i bisect from the center point it doesn't form the side edge of the flap

The diagonals will form one edge of the flap no matter where the tip supposedly is. ut the points that are "off the page" won't be sharp.

at the risk of beating a dead horse...

the edges of the flaps are usually formed by bisected the corner/tip of the flap by folding edge to diagonal fold; i don't understand where the reference for these creases are because they dont pass through the off centered middle point, and the tips of the flaps (normally where the corners are) are yet to be determind... also, balto, you can ignore this if youre getting fed up haha thanks for trying to help

You just treat the corner of the square as if it extended further and align the edge with the crease, like in Satoshi Kamiya's Wizard. The creases/edges don't need to intersect to be aligned.

i tried again... have you physically folded the examples from the pages in the book? i couldnt make what you described work. also, i couldnt find anything in the wizard diagrams that matches what im talking about. i havent actually folded the wizard, though, so maybe im missing something

I'll try to explain tomorrow .

Offsetting a base.
First, I haven't tried this with more elaborate bases but it should work with the general bases. I'll first use the example of a waterbomb base and then the 1 of the offsetted bird bases in figure 4.16 from Lang's ODS.
(the middle one you may figure out yourself )

Ok lets start at the beginning, here is the crease pattern for a waterbomb base:
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The center point has coordinates: (0.5, 0.5) (I take a unit square which means the square has sides of 1 by 1 the half of both is 0.5) I don't know if you know stuff like this but the notation I use is like this:
You can go to the right which I call x and go up y , shorthand (x,y) so (0.5, 0.5) is 0.5 to the right and 0.5 up.

Ok now I decide to move up the center by 1/8 so the new coordinates are: (0.5, 0.625)
It looks like this:
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The black square is your paper the red lines indicate the shifted crease pattern, everything in the black square is your crease pattern)

How would you fold to find the new center? You shifted it up by 1/8, so fold the square in eighths and fold the 45 degree diagonals through (0.5,0.625) or in franctions (1/2, 5/8).

So far so good? Then I'll continue with figure 4.16 from the book, the most right figure.

I drew it like I did with the shifting of the waterbomb base. It is now shifted 1/8th to the right.
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The new coordinates of the center are (5/8,1/2). Now your problem, as I understand is how to fold the right part. The green lines in the next figure are the ones you should be able to fold (the square base + 4 angled bisectors) I will discuss how to fold the red and blue (the red one needs some more construction)
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First the blue's. They are nothing more than folding an angled bisector, I refer you to http://en.wikipedia.org/wiki/Huzita%E2% ... ori_axioms Axiom number 3. You got the lower edge of the paper and the diagonal that crosses through (5/8,1/2). The angled bisector is the one you are looking for so fold like this:

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The last 2 I don't know an "easy" way to fold them (i.e. 1 fold), but you can find them by adding some.
Fold a line like this to find the marking on the horizontal half crease, (x, 1/2).

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This crease is at a 45 degree angle and should go through 1 point you already have. Now you find another point at the horizontal half crease (intersection of your fold and the half) This is the point from which you can find the last 2 red crease.

Okay the easiest way to go now is like this: Fold your bird base completely. You will have one side of your birdbase (see grey triangle below) that looks like this:

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Now fold the edge indicated with the orange arrow on the red line. This is a bisection of that angle. Now you should have found your last 2 creases. Unfold your base and check the creases.

I hope this helps a bit and I let you figure out the middle one of 4.16 yourself. Good luck !

thank you so much! that was very generous of you to take the time to explain that so clearly!!! also, your designs on flikr are awesome... i can't wait to make my own. so far my only design is a hooded figure, a beggar, from a distorted bird base. i want to design something from an offset base before i move on to splitting points. thanks again, that was so nice of you