Science!

Cadaverous Pallor · 10-08-2010, 09:43 AM

I thought of a science question that I'm having trouble googling. Perhaps you braniacs can help out.

Why would a razor (or other sharp metal implement) go dull from disuse?

I understand that certain metals chip away in tiny fractions when used and eventually lose their edge. I also understand that certain metals become sharper with use for the same reason, as the tiny chipping varies due to the properties of the metal.

But to have an object just sit and get dull? My muddy guess is that it has something to do with oxidation, something to do with the air...but to my mind, any dulling from air would take a very long time, unless the razor were in an extreme environment (humid, dry, salty sea air...whatever it is that causes the dulling). When people say "dull from disuse" are they referencing an effect that takes 50 years to manifest? Or, if you buy a very large pack of disposable razor blades, you'll find that the last razor you use is measurably duller than the first?

Thanks for any illumination. Other science questions are welcome here.

Alex · 10-08-2010, 10:14 AM

It is oxidation (even when in use, the actual shaving is not a significant source of dulling as much as the water exposure). Dosn't take a lot to significantly dull a fine edge. And bathrooms, where most people keep their razors are high humidity environments.

This is why my newly opened back of blades (which I bought perhaps 18 months ago are still completely fine, they've been kept dry and away from humidity).

This is also considered an explanation for why those mystical pyramids you can buy appear to help keep razors sharp. The instructions tell you to dry the blade and then you put it under something which protects it from ambient humidity.

Cadaverous Pallor · 10-10-2010, 01:40 PM

Thanks, that makes sense. I wonder if one could market a little box that you can keep your razor in to protect it from humidity in the bathroom....though I suppose using it makes it hard to keep it dry.

You're so reliable, Alex. Will you marry me?

(For the record, GD knew the answer, I just didn't ask him.)

10-08-2010, 09:43 AM	#1
Cadaverous Pallor ohhhh baby Join Date: Jan 2005 Location: Parental Bliss Posts: 12,364	Science! I thought of a science question that I'm having trouble googling. Perhaps you braniacs can help out. Why would a razor (or other sharp metal implement) go dull from disuse? I understand that certain metals chip away in tiny fractions when used and eventually lose their edge. I also understand that certain metals become sharper with use for the same reason, as the tiny chipping varies due to the properties of the metal. But to have an object just sit and get dull? My muddy guess is that it has something to do with oxidation, something to do with the air...but to my mind, any dulling from air would take a very long time, unless the razor were in an extreme environment (humid, dry, salty sea air...whatever it is that causes the dulling). When people say "dull from disuse" are they referencing an effect that takes 50 years to manifest? Or, if you buy a very large pack of disposable razor blades, you'll find that the last razor you use is measurably duller than the first? Thanks for any illumination. Other science questions are welcome here. __________________ The second star to the right shines in the night for you
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10-08-2010, 10:14 AM	#2
Alex . Join Date: Feb 2005 Posts: 13,354	It is oxidation (even when in use, the actual shaving is not a significant source of dulling as much as the water exposure). Dosn't take a lot to significantly dull a fine edge. And bathrooms, where most people keep their razors are high humidity environments. This is why my newly opened back of blades (which I bought perhaps 18 months ago are still completely fine, they've been kept dry and away from humidity). This is also considered an explanation for why those mystical pyramids you can buy appear to help keep razors sharp. The instructions tell you to dry the blade and then you put it under something which protects it from ambient humidity.
	Submit to Quotes

10-10-2010, 01:40 PM	#3
Cadaverous Pallor ohhhh baby Join Date: Jan 2005 Location: Parental Bliss Posts: 12,364	Thanks, that makes sense. I wonder if one could market a little box that you can keep your razor in to protect it from humidity in the bathroom....though I suppose using it makes it hard to keep it dry. You're so reliable, Alex. Will you marry me? (For the record, GD knew the answer, I just didn't ask him.) __________________ The second star to the right shines in the night for you
	Submit to Quotes