Mathematical Crochet Designing

[cookieking]

I have been trying to shape my crochet for a long time now. Do you think I could use math to tell me where to keep the stitches, just like builders use math to know where to keep bricks? If you think so, could you mabye do me a favor and give me a tip on how to do it?

[redrosesdz]

Crochet is all math.  (shh ... don't tell crocheter's who hate math!  LOL) 

When you do flat (square/rectangle) objects, each row has the same number of stitches.  If you increase, you have to skip or decrease to counter the increase.  Flat includes corner-to-corner, because when you're done, the rows have the same number of stitches.  When you do round (round/oval/motifs of any shape) objects, each round increases evenly to accommodate the increasing circumference.  When you're creating odd shapes, you can use increases, decreases, slip stitches, chains, skipping stitches and different stitch heights to create shaping.  For example, the point on a star is often created by chaining a spine, then going up the chain with graduated stitch heights and back down with with the reverse graduated stitch heights.  Another example, a hump is created by graduated stitch heights up the hill, then the reverse back down the hill.  (What I mean by graduated stitch heights is sc, hdc, dc, htr, tr or the reverse.  You can also add any extended stitches in between.)

If you want to learn the math, I suggest mastering fillets, amigurumi and odd shaped motifs from a variety of patterns.  These will give you a wide variety of techniques to understand crochet math.  Once you've done several of these from others, you should have the knowledge to build your own.

I did a search on creating crochet from math and ran across this interesting site ... http://www.crochetconcupiscence.com/2013/01/10-beautiful-examples-of-math-in-crochet-art/

[magiccrochetfan]

Cookie king, what kind of shaping of you want to do?  There are a few different references that might be helpful, depending on whether you want to make garments or 3d things like amigurumi for example.  Also, do you need only online references?  or can you access books via a public library or by purchasing them?  I ask because there are some pretty good books that could help you if you are able to access them, but i know in some parts of the world it can be very difficult to obtain books.  

[Granny Square]

When Redrosesdz described a 2-D hump (like a flower petal for example), it made me think of 3-D shaping which can be achieved by short rows (where you work part way across the fabric, turn and work back and forth in either wider or narrower mini rows (or both), then resume and work over the original length of the fabric again.  This is used in sock heels and bust darts for example.

Speaking of socks, typically the heel turning is over half of the total sock stitches...but patterns may vary from this.

I'm sure no absolute table or formula exists that covers everything.  Where I use math the most is when making a wearable and need to get it to fit, which involves comparing my gauge swatch to the designers' and figuring out what I need to do to create a garment to fit me if it differs.  If my swatch doesn't match the designers' exactly, this involves figuring out the width of MY stitch, and multiplying it across the number of stitches at a meaningful spot (like bust measurement, foot diameter, etc.) and figuring out how far off I am.  Tiny fractions of an inch matter when multiplied by tens or hundreds of stitches; sometimes I end up following the directions for size x to achieve the measurements for size y for example.

There are some guidelines for turning the corner on squares (in the round) for example; 3 stitches in the corner for SC, 5 stitches for DC.  I tend to make the middle stitch a chain when using plain stitches, it makes a sharper corner.  However, if you make really tall or really short stitches, this ratio may need adjusting.

For flat circles...there is a formula for plain stitches: start with 6 for SC, 9 for HDC, and 12 for DC in the first round, and increase by that same number of stitches every round thereafter.  But...that's a 'typical' rule, you might have to modify the number of increases every once in a while to keep it flat with your personal stitch height gauge.

I do agree with just finding different patterns that have a 'how did they do that?' aspect and trying them out.

Here's a site that has a few 'basic shape swatches' that you might find helpful, if you are talking about 3D shapes. http://www.mooglyblog.com/how-to-make-5-basic-crochet-shapes-free-patterns-and-links/

If you are talking about shaping the sides of a flat fabric...I'll use DC as an example...

To subtract from the beginning of the row, if only a couple of stitches you can DC 2 or 3 together; if more, you can slip stitch across stitches; for a sloped transition, you could either slip across a few, then either DC 2 or 3 together or do a sc, hdc, dc and continue (this may not work as well if the shape is symmetrical and needs to continue for another row); for a squared off transition, slip stitch, chain 3, and continue in DC.

To subtract at the end of a row, you can just stop short for a squared off shape; for a sloped shape, DC 2 or 3 together, or a combination.  The hdc, sc slopecould be an issue for the next row however.

To add to the beginning of a row, chain for x stitches plus the turning chain (2 for DC, then turn and DC into the 4th chain).  Or, if just a couple of stitches, DC a few in the first stitch or first couple of stitches.

To add to the end of a row, make foundation DCs (there are lots of tutorials out there if you haven't run across this yet...this is what they call 'figures in the air' in filet).  Or like above if just a few, multple stitches in the last stitch or 2.

Oh dear, all this typing and no surprise someone else has posted.  Hi Magic!

edit-forgot 3D link

 

[cookieking]

45 minutes ago, magiccrochetfan said:

Cookie king, what kind of shaping of you want to do?  There are a few different references that might be helpful, depending on whether you want to make garments or 3d things like amigurumi for example.  Also, do you need only online references?  or can you access books via a public library or by purchasing them?  I ask because there are some pretty good books that could help you if you are able to access them, but i know in some parts of the world it can be very difficult to obtain books.  

I am trying to do 3D shaping, to do amigurumi. I can access both books and online references. I appreciate your help.?

[magiccrochetfan]

June Milbank does amigurumi and her site Planet June has a lot of great info.  Sorry I can't link at the moment.