Thread: Explaining the thumb test

Let's then assume that 2 different thumb tests have been developed over time. I suppose then, that you can choose which one you prefer to use and which one makes the most sense to you. As long as it does make sense and you know why you are using it, yes?

On a side note:

Finger sensitivity was brought up by Joe. I don't have my old neurology books handy, but I do remember that the human finger tip is wired to be extremely sensitive. With training, one can descriminate very fine detail with light touch.

Here's a neat trick that you can try , if you really care. I suspect most won't care a rats @$$, but for those that do:

Take a phone book and place a hair under one page. Lightly brush your finger tips over the page and see if you can detect the hair. Now try it with 2 pages over the hair. Keep going until you can no longer find the hair. How many pages did it take? With practice, you might be amazed at how many pages you can cover the hair with and still feel it. A variation is to have someone else place the hair so you don't know exactly where it is, and see if you can find it with light touch.

Inquiring minds want to know...

Scott

You know what's even more sensitive? The lips and tongue. Call me crazy, but I just tried the lip test. If any of you guys want to try this, I'm not responsible. And please, don't cut off your nose

Couldn't really tell much btw. Maybe my razors are all equally sharp...

Redwoood

Redwoood,

That's just too hardcore for me!

Scott

Originally Posted by honedright

Redwoood,

That's just too hardcore for me!

Scott

Well, I should probably add that I did the 'brushing against it perpendicularly' test, not the other one.
I may be dumb, but I'm not masochistic


Redwoood

So many tests, so many interpretations.
I wonder what test Lynn uses to check his razors.

Originally Posted by honedright

Take a phone book and place a hair under one page. Lightly brush your finger tips over the page and see if you can detect the hair. Now try it with 2 pages over the hair. Keep going until you can no longer find the hair. How many pages did it take? With practice, you might be amazed at how many pages you can cover the hair with and still feel it. A variation is to have someone else place the hair so you don't know exactly where it is, and see if you can find it with light touch.

Inquiring minds want to know...

Scott

That's quite amazing! Now, consider that a hair is about 75 microns and the razor test would be looking for 5 or less.

Originally Posted by Kees

So many tests, so many interpretations.
I wonder what test Lynn uses to check his razors.

I know the answer to that- shaving. That's the only one he admits to.

Originally Posted by Redwoood

You know what's even more sensitive? The lips and tongue. Call me crazy, but I just tried the lip test. If any of you guys want to try this, I'm not responsible. And please, don't cut off your nose

Couldn't really tell much btw. Maybe my razors are all equally sharp...

Redwoood

You mean you didn't try the tongue test?

I don't think that my kind of thumb test requires all that much sensitivity. You're only looking for a good razor grab and the feel of a thin edge.

Originally Posted by honedright

I don't have my old neurology books handy

Does that mean you have medical training? If so, it's no wonder that you're willing to risk removing body parts.

One more reference to the "thumb test" on page 86 of "Barber Shop History and Antiques" by Christian R. Jones. This description is taken from a Moler barber manual:

"...the razor should stick to the ball of the finger or thumb, having the same damp, sliding the razor from the heel to the point. Should the razor feel slick to the ball of the finger, it is in need of more stropping, until it does feel smooth and stick to the flesh."

Notice the barber manual specifies sliding the razor from heel to point. Doesn't sound like brushing the thumb across the edge to me. (the thumb across the edge is a great way to check for a sharp edge on a pocket or kitchen knife, but not on a straight razor).

The barber who showed me this technique didn't slide the razor. He held the razor still and moved his thumb, in tiny increments, with a very light touch, along the cutting edge, from heel to point. A sort of light "tapping" of the thumb along the edge. There was no lateral movement of the thumb or razor.

Scott