Odd question about sharpness.

CrimsonTideShooter

CrimsonTideShooter

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Oct 23, 2010
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I'm pretty surprised at how sharp my edge pro combined with a loaded strop can get my knives. I can easily treetop hair and whittle, and slicing TP is no problem at all.

My question is, how sharp are modern scalpels used in surgery? I'm talking just plain scalpels, not electro-cautery or anything like that.

How would our sharpest edges compare to scalpels?
 
The sharpest cutting edge goes to obsidian blades. At a tiny 3 nanometers thick are still super smooth under an electron microscope, where as a steel scalpel still retains some rough/jagged edges. Can't compete with nature.
 
RevDevil said:
The sharpest cutting edge goes to obsidian blades. At a tiny 3 nanometers thick are still super smooth under an electron microscope, where as a steel scalpel still retains some rough/jagged edges. Can't compete with nature.
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Wow! Thanks for that info.
 
I seem to recall hearing, a long while back, that some (at least) steel scalpel blades are sharpened by electrochemical means (as in etching). I believe this minimizes the jagged edge issues created by abrasive sharpening means.

Scalpel blades also have a built in cutting advantage, in that they're extremely thin, especially at the edge. Many modern medical scalpels & other instruments are intended for very limited usage (even single cuts), before being discarded. Don't have to worry as much about edge retention over the long term, so the edges can be ground extremely thin.
 
If anyone wants I have an article on this very subject. The use of obsidian blades in surgical procedures. PM me if you want it. .PDF format.
 
CrimsonTideShooter said:
That makes sense OWE. Chemical sharpening (etching) sounds interesting.
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It does sound interesting. The thing that bugs me, is I heard (read?) this many years ago, just enough to make it stick in my memory, and wonder how they do it. But it seems to be very difficult to find the details on it. Might be some proprietary secrets in the process. Don't know for sure. I don't doubt that it can be done in a very controlled & automated process (as would be expected for medical instruments), but I wish I knew more about it.
 
even though a scalpel might not be finished to a super fine grit, it's blade geometry allows it to cut the way it does. my sushi knife (yanagiba), even at 1200 grit and stropped will slice through flesh like it was jello.
 
i have an obsidian knife that a friend in indiana gave me. his grandfather was an avid artifact collector/hunter and he gave it to me one day along with several other pieces. a small piece flaked off and it was thin and wicked sharp. i have seen shards of glass that were thin and sharp but none compared to that obsidian piece.
 
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Great point there jimnolimit! Too often we focus on steel and sharpening while forgetting about blade geometry and profile.
Because of geometry and shape, any larger blade won't stand a chance against a scalpel when it comes to sheer slicing sharpness and efficiency.
 
also, im willing to bet that the steel used for scalpels and their heat treat = a very fine grain structure.
 
obsidian flakes were the choice of eye surgeons for many years, lazers dominate at present i believe. i've heard reference of diamond knives used to do superthin tissue slices for medical use but do'nt know much about them.---dennis
 
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