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meteor
March 13th, 2016, 07:44 PM
Hey, guys! :D

I've been thinking about how to make it easier to measure individual hair strand thickness without having any special tools. It seems like many people (myself included) have problems identifying their hair strands as F/M/C, let alone getting a very specific micron measurement. Sure, there are great methods out there: with rulers (http://science-yhairblog.blogspot.ca/2012/06/is-your-hair-fine-medium-or-coarse-how.html) (but it is really hard to keep all strands from overlapping each other), or raw fiber measurements, for example, but that's before those fibers are turned into threads (multi-strand plying structures, twists and wraps all change the measurement), and most of us can't access raw fibers.

So here's an easy way I came up with to get a good approximation.
For this method, you'll need only:
- a ruler or a measuring tape (calibrated to at least millimeters);
- a thick book or multiple books or notepads or a stack of paper for printing (preferably new, not too ruffled).

Steps:
1. Look at the page count (we are assuming that all the pages are still there!)
2. Press down on the book/stack of pages (use a paper weight, if needed).
3. Measure accurately the thickness with a ruler/tape.
4. Divide the measurement by the page count. Now you have the thickness of the paper (a.k.a. the "caliper" in the paper industry).
5. Compare different strands of your hair to that paper thickness. Take pictures, if it helps figure it out better. (Most people will have a combination of different thicknesses growing on different parts of the scalp, so try a few strands).
6. You can continue this procedure with different types of paper to get more and more precise measurement (for example, magazines, postal cards, arts books tend to have thicker caliper)

1 millimeter = 1,000 Ám, i.e. micron (a.k.a. micrometer)

Ranges:
There isn't a standardized approach for this, since hair is organic matter and can have pretty different structures even on the same head.
I'm going to suggest Science-y's breakdown (http://science-yhairblog.blogspot.ca/2012/06/is-your-hair-fine-medium-or-coarse-how.html), though there are many others out there (*):

< 40 Ám -> very fine (**)
40 - 60 Ám -> fine
60 - 80 Ám -> medium
> 80 Ám -> coarse

Additionally, there can be an even more detailed (***) breakdown for coarse hair:
80 - 95 Ám -> slightly coarse
95 - 110 Ám -> moderately coarse
> 110 Ám -> very coarse


* e.g. 17 - 181 microns (http://hypertextbook.com/facts/1999/BrianLey.shtml)
58 - 100 microns (http://www.hair-science.com/_int/_en/topic/topic_sousrub.aspx?tc=ROOT-HAIR-SCIENCE^PORTRAIT-OF-AN-UNKNOWN-ELEMENT^WHAT-WE-DO-SEE&cur=WHAT-WE-DO-SEE)
< 40 microns = fine; 70 microns = medium; > 110 = coarse (http://www.philipkingsley.co.za/hair-types)
** From a sample Goosefootprints report (https://www.etsy.com/listing/165203245/mini-hair-physical-analysis?ref=shop_home_active_2)
*** From this post (http://forums.longhaircommunity.com/showthread.php?t=128902&p=2919724&viewfull=1#post2919724)


Additional note for coarsies:
Another thing worth comparing to is a toothbrush bristle. (It's easier to compare if you cut a small piece of hair the same size as a tooth brush bristle and lay them next to each other.)
Different sources give different measurements for tooth brush bristles, for example:
- 300 microns (http://extension.oregonstate.edu/wasco/sites/default/files/smallfarms/featured-articles/pesticides/DriftManagement0904.pdf);
- 200 (soft bristle), 300 (medium bristle), or 400 (hard bristle) (http://www.ijdr.in/article.asp?issn=0970-9290;year=2006;volume=17;issue=4;spage=167;epage=1 70;aulast=Sasan)
But despite the variation, all the measurements I've seen are still way above the threshold for coarse hair, so if your hair is comparable to a toothbrush bristle, it's probably very coarse. ;)


Additional note for fineys:
And if your hair is more on the really fine side of the spectrum, spiderweb from a garden spider might be worth a look. :)
Garden spider's silk is on average 3-4 microns (http://web.mit.edu/3.064/www/slides/Ko_spider_silk.pdf), so 10 times as thick as silkworm's silk (http://www.earthlife.net/chelicerata/silk.html)
This electron microscopic study (http://www.optics.rochester.edu/workgroups/cml/opt307/spr07/luke/) contains a very cool picture (http://www.optics.rochester.edu/workgroups/cml/opt307/spr07/luke/HAIR3.JPG) (and this one (http://www.optics.rochester.edu/workgroups/cml/opt307/spr07/luke/TWOHAIR.JPG), too) that shows how tiny a spiderweb silk fiber is when it's placed on top of coarse (80 microns) hair: the measurement in this case for spider silk was only 1 micron.
Basically, if the hair is even somewhat comparable to spider silk, it's probably very fine.

Hope this can help someone who may be having problems figuring out their hair strands' thickness! :flower:

AJNinami
March 14th, 2016, 12:11 AM
Wow, thank you meteor! I've just kind of assumed my hair was medium all this time, but I think I might try this to get a specific measurement!

Someone should add a link to this on the hair-typing page. :wink:

Arctic
March 14th, 2016, 03:35 AM
Great ideas! I'm going to try your book method some day, very clever!

meteor
March 14th, 2016, 01:04 PM
Great! :D I hope it works for you, guys! And if it's hard to see, using a magnifying glass or simply running a dark marker on the edge of the page (to see it better) can help.
By the way, I'd recommend first picking out the books/notebooks with pages that have caliper / thickness that's visually somewhat close to the thickness of the hair strand(s) you are testing. And then going from there with the whole "book thickness / page count" calculation! This will save some time. ;)

butterflybutton
March 14th, 2016, 08:12 PM
This is amazing! Thank you meteor��

SparrowWings
March 14th, 2016, 09:56 PM
You should link to this thread in your Hair Science Thread, too, as an alternative to the lined up hair method under Hair Thickness. Much easier to find it then, than by hunting out this thread separately in the full forum!

meteor
March 14th, 2016, 10:16 PM
^ Thank you, SparrowWings! Good idea! :thumbsup: I've just added the link in the Index (http://forums.longhaircommunity.com/showthread.php?t=136845&p=3187904&viewfull=1#post3187904) there (under the Hair Strand Thickness).

pinutzz
March 20th, 2016, 06:01 PM
This is a great idea! So I had to try it out immediately!
I took a stack of 500 pages of printer paper, which is almost exactly 5cm high. This gives us a paper thickness of 100 micron. When I compared my hair to the paper, the hair looked and felt a little thinner than the paper, so my guess would have been 80 micron = coarse hair. However I know that my hair is very fine - every time I go to the hairdresser they tell me that I have extremely fine hair. The picture on my profile page actually makes my hair look much coarser, but that was just after a cassia treatment, which coats the hair and makes it thicker and also makes it look a lot fluffier. My avatar gives a much more realistic impression.

Then I compared a shed hair with the paper under a microscope and I saw that the thickness of the paper actually varies a lot (+- 30%) and that the paper is very fluffy (more like fairy tail ends) and didn't really have a clear edge, while I could discern the edges of my hair easily. I was really surprised that it had the same thickness everywhere (except at the very ends). Even though I could see that my hair was a little less thick than the paper I had a very hard time judging by how much - even under the microscope.

I work in an optics lab, so I compared my hair to optical pinholes in different sizes (http://www.thorlabs.de/newgrouppage9.cfm?objectgroup_id=1400) under the microscope and that worked much better. I found my hair to be about 50 micron thick.
Then I took a micrometer screw gauge to actually measure the thickness of my hair and no matter what hair I took and which gauge I used I always got 45 micron. I was worried the hair might have gotten squeezed flat by the screw (I was very gentle though), but since it matches my microscope measurements I am pretty confident that this is correct.

At least for me the paper method didn't really work :shrug:

ETA: printer paper was 80g / m^2

Beborani
March 20th, 2016, 06:17 PM
Sewing thread? Their thickness must be standardized no? And probably published somewhere? I don't sew so don't have actual knowledge but if there are threads of differing thickness it should be really easy. I have handled hair that is finer than mine and coarser than mine in my family, so I put mine in medium category.

lapushka
March 20th, 2016, 06:18 PM
One of my former hairdressers had a measuring tool to measure the strand thickness of an individual strand (mechanical tool). And mine was fine, so that's how I know it is. My white hairs are even finer, because I can visually see that when holding them between fingers. So yeah. Sometimes I have a normal strand fall out and it is noticeably thicker.

Nice idea, though.

meteor
March 20th, 2016, 07:06 PM
This is a great idea! So I had to try it out immediately!
I took a stack of 500 pages of printer paper, which is almost exactly 5cm high. This gives us a paper thickness of 100 micron. When I compared my hair to the paper, the hair looked and felt a little thinner than the paper, so my guess would have been 80 micron = coarse hair. However I know that my hair is very fine - every time I go to the hairdresser they tell me that I have extremely fine hair. The picture on my profile page actually makes my hair look much coarser, but that was just after a cassia treatment, which coats the hair and makes it thicker and also makes it look a lot fluffier. My avatar gives a much more realistic impression.

Then I compared a shed hair with the paper under a microscope and I saw that the thickness of the paper actually varies a lot (+- 30%) and that the paper is very fluffy (more like fairy tail ends) and didn't realldy have a clear edge, while I could discern the edges of my hair easily. I was really surprised that it had the same thickness everywhere (except at the very ends). Even though I could see that my hair was a little less thick than the paper I had a very hard time judging by how much - even under the microscope.

I work in an optics lab, so I compared my hair to optical pinholes in different sizes (http://www.thorlabs.de/newgrouppage9.cfm?objectgroup_id=1400) under the microscope and that worked much better. I found my hair to be about 50 micron thick.
Then I took a micrometer screw gauge to actually measure the thickness of my hair and no matter what hair I took and which gauge I used I always got 45 micron. I was worried the hair might have gotten squeezed flat by the screw (I was very gentle though), but since it matches my microscope measurements I am pretty confident that this is correct.

At least for me the paper method didn't really work :shrug:

ETA: printer paper was 80g / m^2

Brilliant!!! :thumbsup: I love your approach! I just wish I had access to tools like that!
Yes, unfortunately, paper caliper can be varied. Sad but true. Paper companies try to make the thickness as consistent as possible and often advertise their caliper # in microns, but it still can have some variation. :(


Sewing thread? Their thickness must be standardized no? And probably published somewhere? I don't sew so don't have actual knowledge but if there are threads of differing thickness it should be really easy. I have handled hair that is finer than mine and coarser than mine in my family, so I put mine in medium category.

If your hair strands are as thick as sewing thread, your hair is probably mega-coarse. :D I've looked at a bunch of data on measurements of all sorts of different fibers (natural and synthetic) in microns, but that's not what you get when you buy sewing thread: thread has a concept of ply (http://media-2.web.britannica.com/eb-media/82/1682-004-02419DC2.jpg), and that messes up the measurement completely, not only because you have many fibers combined together (that could be easily solved by adjusting thickness by given ply count), but also because the exact way they were combined/twisted together will change the thickness as well, enough to throw off the measurement completely.

But if one has access to the original fibers, it would really work for comparing to hair! ;)
There is *lots* of information online about thickness of different fibers, e.g.:
http://www.shepherdesswool.com/uploads/2/6/5/9/26595193/if-fiber_fineness.pdf
http://www.wildfibres.co.uk/html/fibre_size.html

The problem is getting access to these fibers and also, organic fibers can be diverse in thickness, as well as our own hair, obviously. ;)


One of my former hairdressers had a measuring tool to measure the strand thickness of an individual strand (mechanical tool). And mine was fine, so that's how I know it is. My white hairs are even finer, because I can visually see that when holding them between fingers. So yeah. Sometimes I have a normal strand fall out and it is noticeably thicker.

Nice idea, though.

Awesome! :thumbsup: That tool sounds really cool! Do you know what kind of tool it was? I really wish hairdressers around here used something like that (or any measuring tools, for that matter)!

Beborani
March 20th, 2016, 08:13 PM
I googled just once for embroidery floss--I was thinking of that while I wrote sewing--to me they all fall in the same category--things I don't do:) and found this. Seems like it will be helpful.

http://sprint-romania.com/pagini/thread_carefully_small_embroidery_string_guide

There are lots of crafty people here who will know more.

meteor
March 20th, 2016, 08:46 PM
^ :thumbsup: Oh yes! I'm sure we have crafty LHCers who will have access to those embroidery things! :agree:
Thanks a lot for the great tip, Beborani! :flowers:

Crystawni
March 20th, 2016, 08:52 PM
I'd also note when measuring that weather and other moisture can play a part in how thick/thin your strands can look, and can make paper swell and shrink too, thus skewing the results.

meteor
March 20th, 2016, 09:03 PM
^ That's very true, diameter of hair can increase by 15% to 20% when it's wet (http://www.hair-science.com/_int/_en/topic/topic_sousrub.aspx?tc=root-hair-science%5Eso-sturdy-so-fragile%5Eproperties-of-hair&cur=properties-of-hair)! :agree:

lapushka
March 21st, 2016, 05:36 AM
Awesome! :thumbsup: That tool sounds really cool! Do you know what kind of tool it was? I really wish hairdressers around here used something like that (or any measuring tools, for that matter)!

It was tiny. Fit into the palm of her hand, with a small dial on it that must have indicated the Ám. I remember she came up to me, behind me, and took a strand to clip into the tool. It was a bluish gray color. I didn't ask where she got it but I got a good look at it (of course anything they put into your hair, you're weary of). I was a teen back then and thought it was sooo strange of her! I thought she was a little off and weird TBH. :lol: Of course I didn't know squat about hair back then. She thought it was funny of me to have F hair and so much of it. Like she'd never seen it before. :rolleyes:

meteor
March 21st, 2016, 10:26 AM
It was tiny. Fit into the palm of her hand, with a small dial on it that must have indicated the Ám. I remember she came up to me, behind me, and took a strand to clip into the tool. It was a bluish gray color. I didn't ask where she got it but I got a good look at it (of course anything they put into your hair, you're weary of). I was a teen back then and thought it was sooo strange of her! I thought she was a little off and weird TBH. :lol: Of course I didn't know squat about hair back then. She thought it was funny of me to have F hair and so much of it. Like she'd never seen it before. :rolleyes:

^ Sounds awesome, lapushka! :applause
I *really* think this tool could be useful for hairdressers that are preparing to use bleach or dye or perm or relaxer or Brazilian/Japanese keratin treatment kind of services... just to help them ascertain that the client's hair will withstand the processing. Over here, at best, they just look at your strands and touch them and ask about your hair history (how it responds to this or that procedure) and that's it. But I think more detailed assessment would be helpful, just to prevent those hair disasters when hair can start breaking off after a treatment, etc.

lapushka
March 21st, 2016, 10:49 AM
Yes, she was a really careful hairdresser, had done her "apprenticeship" at my grandma's salon (which was really old school, lots of perming and coloring and short cuts, lots of older ladies). I had never seen anything like that before, but she'd never seen someone with my hair before either - which is probably why she was that puzzled by it. It makes me wonder, though... How much they really teach in schools. I mean, it was as if I was a freak of nature. :lol:

CosmoCat
June 24th, 2019, 03:09 AM
I hope it’s ok, I’m bumping this thread, it’s helpful.

My husband tested three random strands of mine and they were 18, 35 and 39 microns thick. So, according to the information on this post, my hair is “very fine”.

https://forums.longhaircommunity.com/attachment.php?attachmentid=37418&d=1561361203

CosmoCat
June 24th, 2019, 04:35 AM
It was tiny. Fit into the palm of her hand, with a small dial on it that must have indicated the Ám. I remember she came up to me, behind me, and took a strand to clip into the tool. It was a bluish gray color. I didn't ask where she got it but I got a good look at it (of course anything they put into your hair, you're weary of). I was a teen back then and thought it was sooo strange of her! I thought she was a little off and weird TBH. :lol: Of course I didn't know squat about hair back then. She thought it was funny of me to have F hair and so much of it. Like she'd never seen it before. :rolleyes:

I wonder if the tool was a micrometer? My husband was just telling me that we can buy one...fairly inexpensive.

I have been told twice over the years, while at salons, that my hair was “really fine, but a lot of it” too! I’m only an “ii”, however, at 2.75” base of pony tail.