Thread: HHT: Should the type of hair matter?

When I perform a hanging hair test (HHT) using my own hair, it almost always fails. I have a full head of hair, but the individual hairs are fine. On the other hand, if I use one of my wife's hairs, which are easily found on the bathroom floor, the HHT is almost always successful. Compared to me, her hair is course.

So am I cheating? Should I expect the HHT to be robust and work for all types (diameter) of hair?

Human hair varies a great deal, and so do results from the HHT. My own head hair is very fine, as is my wife's, but her best friend has hair like black cables. After finding a few on the sofa, I told her she had to leave me some every time she stopped by.

In general, the HHT is only useful once you already pretty much know what you're doing. Then you can say "when I've sharpened a blade to this stage, I get these results, and at this stage, I get these results", etc.

Variation is insane, and also technique. In the first 7 wks, I couldn't get a blade to lop a hair of any kind for any reason. That included a blade professionally honed on shapton 30k. That blade was so sharp it would turn a Thumb pad test into a rib cage test - but I couldn't lop a hair with it.

Hair. One time a member asked about variation in hair - if anyone w/ a micrometer had ever measured. My chest hair came in at .0033" and head hair came in at .0018. That's getting pretty fine - in a way you don't want. A bit of experience, and I lop both, and with some practice w/ slurry on the finishing stone, I get smooth also.

Don't let the HHT be a holy grail. JimmyHad has posted more than once that he doesn't do that test much now - relies on feedback from TPT. I would agree, though less experienced.

your experience just indicates that HHT is not very reliable test.
TPT would give you much better idea where the edge is, after some practice you will be able to read the feed back rather well.

In the end the real test is the shave test.

I usually use the HHT test at the end of all my tests (right before i do the actual shave test, the only test that matters) for me , I know that if it passes my own hair HHT then i can move on to the shave test , if it doesn't pass then it needs some more love on the hones. With that said I use the TPT and AHT the most when checking my edges, the HHt is just the icing on the cake

Antenna60,

As I have a high & tight haircut, the only hair in the house for the HHT is my wifes very, very fine hair.

No commercial DE blade will pass the HHT with her hair, and very few of my straights do.

However, all my straights shave great !!

Moral of the story - it is the shave that is the ultimate test

Please do not get hung up or anxious over the HHT

Have fun !

Best regards

Russ

Originally Posted by northpaw

... In general, the HHT is only useful once you already pretty much know what you're doing. Then you can say "when I've sharpened a blade to this stage, I get these results, and at this stage, I get these results", etc.

I agree totally! And, I think it could be stated more generally for almost every sharpness test. Restating...

You have a nice shaving razor that is undoubtedly nicely sharp. Apply the HHT to that edge aggressively. Maybe spend 15 minutes, using 100 hair (making a point), cutting hair. When you are done, little pieces of hair should litter the table! More importantly, when you are done, you should have a good idea how a nicely sharpened blade cuts the hair you just tested.

Not all hair out of a head are identical. That is another reason why you must cut up many hair during the above calibration; the determine the variation in your hair. (I use my hair, and when I pull out a thinner hair with a "certain" look to it, I just throw it away.)

Similarly, with nicely shaving razor in hand, apply the TPT over the entire blade, noting how it feels.

It is very important to calibrate your shave ready razor in some process like that above. In my opinion, it is almost as important that you go thru the same process while you are honing it...

Start with a dull Ebay special. Apply the HHT and TPT aggressively. Take 10 passes on the 1K and repeat your tests. Frequently, while honing, stop and repeat testing.

By frequent testing along the way to sharpness you will develop a sense of the state of a razor that is better than just testing shave ready razors.

With combined use of the TPT and HHT I believe it is possible to determine the state of a blade edge quite accurately. But, only after extensive testing and calibration. Otherwise, they both are simply parlor tricks.

If you find a gal with hair that passes your HHT easily, marry her. You'll live happily ever after.

I have several types of hairs and each interacts with the edge differently. I can perform a useful test with any of them.

Using hair is definitely an unreliable variable when it comes to the edge preparation equation. Without really knowing the hair you are using it can be easy to discount the method as a myth or very unreliable at best. I know myself that I can tell at what stage most of my edges are at using three different types of hair.

Saying that, some edges do not react the same as others to the very same hair.

Experience is key in understanding the relationship between your hair of choice and your edges.