Hanging Hair Test

AJP

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When doing the hanging hair test, should the hair be cut just by resting the hair on the blade, or is it right that some downward pressure is required on either or both ends of the hair?

I am sure the "Pulling" sensation this morning on my first straight shave was due to my anle/technique, but i have now stropped the blade too and used that test to check the blade.

Thanks guys,
 
A good article that, but don't drive yourself to distraction with the HHT. A shave is still a more useful gauge of performance really. When Neil drops by he'll probably have something to say about hones which produce superb edges that don't do very well with hanging hairs.
 
In my experience you can't just rest the hair on the blade and its own weight cuts it. You have to apply downward force, but only holding onto one side of the hair.

First time I ever did it I went white, I couldn't believe anything could be so sharp, and also that I was going to put on on my face :shock:
 
A hht doesn't always show if a razor is shave ready, i have one from rasurpur who is known to be on of the best and that one doesn't pass, shaves beautifully however. :cool:
 
Cool ok thanks.

Guess i just wanted to know that i hadn't knackered the edge in my 1st attempt at stropping :lol:
 
Mate I was exactly the same with my first straight. I thought I'd carked the edge up with the strop. Then I got my second, and Neil Miller restored it and put an edge on it that would slice the nadgers off a bluebottle, and I realised I actually hadn't ruined the edge on the first one, just that my technique was all wrong. I'm still learning.

Hardly anyone uses straights these days, so you have no point of reference as to what's good or bad, right or wrong. That's why this site is an absolute blessing, cos people in here know stuff and give freely of their knowledge and experience.

I feel a wee cry coming on...
 
(I posted an abbreviated version of this on another forum - B&B (gasp!) some time ago....)

I agree that the HHT is not an infallible test - I have had good shaves from razors that wouldn't pass the HHT, but - in common with a lot of people - I have never had a bad shave from one that did pass the HHT. I think the ability to pass HHT is due to both the blade and the hair being used.

If hone a razor on a coticule and try HHT - probably it will not pass (I'm talking about straightforward honing, no drawn-out dilution methods and not using a tape for the final bevel). I can strop the blade and it may or may not pass. If I use CrOx before stropping, it will pass. It is probably well-known that the much-vaunted smooth shave given by a coticule is a function of how it rounds the edge of the blade slightly (putting it simply), so this smoothing of the cutting edge has a direct influence on the HHT (once again, I'm talking about straightforward honing on a coticule - as far as I am concerned, the last thing that refines the blade is the edge you are feeling - if you use CrOx after a coticule then you are experiencing the CrOx edge, not the edge left by the coticule).
Perhaps the main contributing factor as to whether the HHT is passed or not is the hair itself- hair may look like very even and glassy-smooth to the eye, but the microscope shows it to be covered in scales, much like the bark of a monkey-puzzle tree. The scales lay in one direction - if an edge is moved along the direction of growth (ie from scalp to end of hair) it would meet no resistance, if it moved the other way it would snag on each scale. If the edge in question is the edge of a razor, then to be able to snag it must be fine enough to push against the raised edge of the scale, so a blade honed purely on a coticule for instance is usually too rounded (without further refinement) to feel the resistance and does not snag. It doesn't mean that it will not give a good, satisfying shave though in much the same way as an axe laid gently on your neck won't cut it - but it's still capable of chopping your head off!

To increase the chances of passing the HHT, the 'bulb' or root of the hair should be facing away from you so the downward action of the hand holding the hair brings the upraised edges of the scales into contact with the blade. The test is performed by slowly bringing the hair down onto the blade and following through - not by forcing the hair, moving it quickly, slicing with it, etc.

Everyones hair is different - the scales ("cuticle" technically) on one persons hair may be very fine and even and not stand out much:

fig1.jpg


while another persons may be in less good condition:

fig2.jpg


You can see that a razor's edge would easily snag against the upraised scales in the second photo. IMO the serrations on the razors edge have nothing to do with it - it's the scales on the hair that matter and whether the bevel is slightly rounded or very acute. Lots of things affect the success of passing the HHT: the type of hone, how much slack given when stropping (ie stropping rounds the edge), the type of strop you use (paddles do not round to the same degree as hanging strops), your hair type, the condition your hair is in, the humidity (the scales become less prominent as humidity rises), etc, etc. Some people say that the hair should be tested before stropping, as stropping increases the chances of passing - so what? We are only after a decent shave after all, not a set of self-imposed rituals.

To some up with, the HHT is not fool-proof and can even be inconsistent with the same persons hairs on different days, but coupled with a shave test it can soon be a good indication of how the razor will shave and be a ggod benchmark for a honer. Th ultimate test is the shave test though - actually shaving with the razor. As stated before, some razors that do not pass HHT give outstanding shaves.

All this is just my personal opinion though - YMMV.

Regards,
Neil
 
I think that was the definitive answer. :lol:

It's certainly my experience that some hairs cut more easily than others, as Neil said. Mine are easy, but if I borrow one from my wife's hairbrush it's a different story. I've only once been successful with one of hers - would it surprise anyone to hear that Neil honed that razor?
 
I have a theory that "dead" hairs are harder to cut than freshly plucked or tweaked hairs. This is based on no scientific experimentation whatsoever, just a general kinda meh experience with hairs I've found lying around in the bathroom. It's like they're just more limp. Maybe, from Neil's writings, the scales all lie down on hairs once they're plucked.

I'm rambling a bit here, I'll get my coat.
 
Arrowhead said:
I think that was the definitive answer. :lol:

It's certainly my experience that some hairs cut more easily than others, as Neil said. Mine are easy, but if I borrow one from my wife's hairbrush it's a different story. I've only once been successful with one of hers - would it surprise anyone to hear that Neil honed that razor?

I've just been using my own hair. I'm off to find my wife's hairbrush now. If I'm struggling to get a razor to pass I'll just head for the rabbit, guinea pigs and cats :mrgreen:
 
Given what Neil showed with his culled-from-a-shampoo-and-conditioner-advert science bit, could it be that effete "lady hair" that fails the test has been better treated and conditioned and is thus floppier and more flexible than hard "manly hair" so tends to wrap over the edge rather than be cut?

ie. all you pooves (given that the other term I'd have used is horses hooves, I think that's the correct plural :lol: ) that use conditioner won't get the HHT test to work because you have "lady hair" :ugeek:
 
hunnymonster said:
ie. all you pooves (given that the other term I'd have used is horses hooves, I think that's the correct plural :lol: ) that use conditioner won't get the HHT test to work because you have "lady hair" :ugeek:

"Irons" in my neck of the woods.

On a different tack, did anyone make one of those weather indicator things at school? When I was a kiddie (neolithic age) we put a pin through a bit of card and through the end of a drinking straw. The pivot end of the straw had a piece of hair tied round it and secured to the base of the card, the whole thing standing upright so that the straw was balanced. If the relative humidity changed, the hair either grew or contracted, making the straw go up or down. You could tell what the weather was going to be like by watching the straw move (or, alternatively, looking out the schoolroom window).

Regards,
Neil
 
Somewhere amongst the piles of books here there's one on hygrometers. From what I remember the expansion and contraction of a human hair was long used in fairly sophisticated instruments, and maybe still is. Googling "hair hygrometer" will more than satisfy your curiosity CD.
 
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