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String length - mathematical solution by lele97 7 years ago

Hey, people!
A long time ago I found a forum thread about calculating string length and since then, I've started calculating my strings length that way. Most of the time, it works nicely.
So I was thinking about making a tutorial about it, but first, I would love to see if it works for others too.

If you want to help me, here is the formula I use:

IMPORTANT!! I use emboidery floss - I don't know how it works for other materials!

http://www.createforless.com/p-images/3/2002/0305/31759-3-1.jpg

number of times the specified string is used for a knot (in one repetition of pattern) = K
number of times the specified string is NOT used for a knot (in one repetition of pattern) = N
number of times the pattern must be replicated to complete the bracelet = P
braid length = B

Using cm:
minimal yarn length = P*(K*0,95 + N*0,3) + B

Using inch:
minimal yarn length = P*(K*0,38 + N*0,12) + B

RE: String length - mathematical solution by kleinevos (moderator) 7 years ago

It might be too simple like this, because forwardbackward and backwardforward knots take more string than regular forward or backward knots. Plaid patterns also take more string than other patterns I think.

I'll try it for my next bracelet though :-) But I always prefer having long leftovers than running short, and this formula takes a lot of time counting knots. I don't think I'll be using it myself.

RE: String length - mathematical solution by lele97 7 years ago

I know, that's why I'm unsure about it, and of course it is useful only for smaller patterns (or patterns, where most of strings are used for same amount of knots, like #9001 or #60267, because most of the strings (maybe all of them) will be the same length).
But I've always had either too long (leftovers 1+ meter long) or too short strings and that's why I started using it. :D
And thanks for giving it a try :)

RE: String length - mathematical solution by Mistalcreth 7 years ago

Oh man, it would be brilliant if this was built in to this site.

RE: String length - mathematical solution by lele97 7 years ago

It would, but I guess it's a little too complicated and it need some testing with different string types/patterns etc. :)
So, for the time being, yay for bracelet math :D

RE: String length - mathematical solution by elizabeth_s 7 years ago

I think it doesn't need to be this complicated though. Once you've made a few bracelets you realise that the strings are pretty much the same length for any bracelet.

If you use at least 100cm of thread per string, (maybe 120cm if you like long braids) that will do it. You can tell by looking at the pattern which colours need more thread.

I have made literally hundreds of bracelets and have never needed to painstakingly calculate string length - even when I first started as a kid.

If this method of calculation helps some people then fair enough, but I wouldn't want this to scare off beginners!

RE: String length - mathematical solution by lele97 7 years ago

I think it's different for everyone - when I was a beginner, I wanted to know how long strings will I need - the more accurate, the better :)
Do you really think it is that complicated? Because it has never taken me more than 10 minutes to measure all my strings (using this method)... Maths can look complicated, but it's pretty easy, actually :)
And it has saved me a lot of material (when you live in small village and don't have the chance to just go and buy material everytime you need it, it changes your point of view on these things ;) )

RE: String length - mathematical solution by kleinevos (moderator) 7 years ago

I've tried your formula in two different bracelets so far, and I must say it surprised me how accurate it is! It looks like bf- and fb-knots also don't take much more string than regular knots, but both patterns didn't have a lot of them so I can't say for sure yet.

I'm still not going to use it a lot because of the counting. I like having long leftovers to use for kumi-making anyway :-)
But I can imagine it'll help a lot of people and I can imagine using it myself for special strings that are usually more expensive than my regular crochet-yarn.

If you still plan on making a tutorial: You can add it to the existing tutorial, it'll be easier to find if there's only one and we'll most likely merge them anyway :-)

RE: String length - mathematical solution by lele97 7 years ago

Thank you for trying it :)

Also, I've wanted to add it to one existing tutorial ;) I will wait a little more, maybe someone else will try it and tell me if it works for them too :)

RE: String length - mathematical solution by Ukiedancer 7 years ago

I'd like to use it with my next bracelet! I didn't do it with the one I currently working on, because I don't want to run short of string in case the calculations didn't work out.