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DreamSheep
January 13th, 2015, 10:08 AM
So I'm practicing some maths and programming skills, and the LHC geek inside me is trying to write some code to calculate how long your hair needs to be in inches to achieve certain buns, given your ponytail circumference in cm. I've written some veeeeery basic code for LWB, my Nautilus bun and a Figure of 8 bun, but was wondering if people could post at more or less what length in inches they could get these buns to work (measured the LHC way), and ponytail circumference, just to see if my approximations are correct. Particularly with the Figure of 8 bun I think I've not chosen the best way to break it down, but if I get a nice model, it would be a nice resource to go on. :)

gwenalyn
January 13th, 2015, 12:06 PM
This is very interesting! I've always thought that "braid bumps" might have a good correlation with what hairstyles work, because it would account for thickness, taper, and texture. I don't know how to collect the data though--maybe check out the "Count your braid bumps" thread?

two_wheels
January 13th, 2015, 02:12 PM
You presumably want stretched length for non-straighties?
I could first do a LWB when my hair was about 22" stretched. A bit shorter maybe. Circumference was 3.25".
I managed my first figure 8 bun today :) 26" stretched / 24" wavy. Circumference is probably the same but I don't want to measure right now.

Arete
January 13th, 2015, 07:55 PM
Oh, this is interesting. I've never attempted a figure 8 until my hair was about 2.5" from BCL unstretched/just shy of BCL stretched. My guess is I could have pulled it off at a little past waist length, so I'll say 32/33" I have a ponytail circumference of 4.25"

DreamSheep
January 14th, 2015, 03:03 AM
Thanks for this guys! I converted the circumference to cm - this is what my programme returns. Based on your replies, I am going to guess that Helix bun and Figure of 8 bun are a bit off. I added 22cm to the ponytail length for it to be LHC length, so if you take 8-9'' off the final value, that would be the needed ponytail length. However, it also assumes there is no taper, so I guess this would ideally give an upper bar for how long your hair would need to be, on the other hand, on some other buns it seems. That said, based on what you guys say, it seems like it might be a bit off (overestimating on Figure of 8 and helix, possibly underestimating on LWB and Nautilus?).
More replies are encouraged! If your hair is already long enough to make a bun, you could make it and then mark with your fingers where the minimum length needed ends, and calculate more or less how many extra inches/cm of hair you have to get an idea of the needed length.
I feel so geeky doing this! :p

You presumably want stretched length for non-straighties?
I could first do a LWB when my hair was about 22" stretched. A bit shorter maybe. Circumference was 3.25".
I managed my first figure 8 bun today :) 26" stretched / 24" wavy. Circumference is probably the same but I don't want to measure right now.

Nautilus bun (the type I make with a half twist): You need 60.1 cm or 23.6 inches
LWB: You need 47.4 cm or 18.7 inches
Figure of 8 bun: You need 69.3 cm or 27.3 inches
Helix Bun: You need 85.8 cm or 33.8 inches


Oh, this is interesting. I've never attempted a figure 8 until my hair was about 2.5" from BCL unstretched/just shy of BCL stretched. My guess is I could have pulled it off at a little past waist length, so I'll say 32/33" I have a ponytail circumference of 4.25"

Nautilus bun (half-twist): You need 68.1 cm or 26.8 inches
Lazy Wrap Bun: You need 55.3 cm or 21.8 inches
Figure of 8 bun: You need 90.7 cm or 35.7 inches
Helix bun: You need 112.3 cm or 44.2 inches

Wildcat Diva
January 14th, 2015, 05:55 AM
What about taper considerations?

DreamSheep
January 14th, 2015, 07:07 AM
What about taper considerations?

Taper is not really accounted for unfortunately (although I would like to), but in some of the formulas I have acknowledged this possibility.
The measurements should theoretically apply for blunt hemlines, but a lot of buns I think mostly depend on circling round a thick central piece, so a minimum length is needed anyway. :)

Arete
January 14th, 2015, 07:40 AM
For the helix bun, I've estimated that I'd need to be between TBl and Classic for it to work, and 44" is about in the middle of those two. :D

Timea
January 14th, 2015, 07:43 AM
i needed about 85 cm before i could do nautilus. my circumference is 13cm.

Seventy7
January 14th, 2015, 02:20 PM
I found out today that I can just make an LWB. And the shortened chopstick my DH sanded down for me holds it just lovely.

I measured a about 2 weeks ago at 53cm, and my ponytail is 5cm. I think I have a few cm spare in the bun, if I was pushed.

I guess I would have to double my length to do the pretty helix bun.

two_wheels
January 14th, 2015, 02:46 PM
Nautilus bun (the type I make with a half twist): You need 60.1 cm or 23.6 inches
LWB: You need 47.4 cm or 18.7 inches
Figure of 8 bun: You need 69.3 cm or 27.3 inches
Helix Bun: You need 85.8 cm or 33.8 inches


I think the LWB is a bit off for me - I definitely tried & failed many times before I got to 22"! Figure 8 sounds near enough (I have very little left over, and did it on a small hair day at 26" stretched). Excited about the idea of being able to do a helix bun in 18 months!

DreamSheep
January 14th, 2015, 04:46 PM
I hope that is the case two_wheels!! :)
That is assuming I've:

a) Interpreted correctly what is going on in a helix bun (cos I can't do one yet :p)
b) Turned it into a proper formula

There are some pretty graphs that come with this which essentially suggest to me they may be a little off, which is why I like to have real numbers from people, so I can try and tweak it better.
Anyway, I could say I'm somewhat kicking myself for not knowing more geometry-mathematics-algebra-dadadaday stuff to apply it better. On the other hand, I'm learning cool stuff. :-)

burny
January 14th, 2015, 05:56 PM
my ponytail is 6", I have about 38", and I can't do a nautilus yet.. about 4-6" short of being able to do one with half a wrap, or 18" from being able to do a proper 1.5 wraps. what's your formula say it should take?

question about ponytail size though: how tightly are you supposed to squeeze porous hair? because I get about 5.9-6" when I squeeze it, but it's almost 8" if I leave it a bit looser/twisted, as I would for a bun/braid.