Russ,
I use tungsten carbide knives for frozen undecalcified bone sections of
rodent tibias and femurs. I try to limit the amount of trimming necessary by
having the bone frozen so that I'm quickly able to get to the area I need
and I trim on one section of the knife only, reserving the rest of the blade
for sectioning. I do all my sectioning on a motorized cryostat so that I can
set a trim level. I find this really helps preserve the knife by not
accidentally cutting a vary thick section that quickly dings the edge. Also
cutting rate is important. If you cut too fast the edge does last as long.
If I'm sectioning several hours per day I find I need to send the blade for
sharpening about every week and a half. I know that doesn't really give you
an idea of the number of blocks I'm cutting, but that really varies
depending upon the type of bone, age of the rodent, and the intended use of
the sections. Since I've never really counted the number of sections my best
guess is that I cut between 40 and 80 bones per blade. Hope these ramblings
and guesses may help.

John Tarpley 15-2-B
Specialist Image Analysis & Immunohistochemistry
Amgen Inc
One Amgen Center Drive
Thousand Oaks, CA  91320

Views expressed are mine alone and do not represent the views of my employer


> ----------
> From: 	RUSS ALLISON[SMTP:Allison@cardiff.ac.uk]
> Sent: 	Tuesday, August 24, 1999 10:14 AM
> To: 	histonet@pathology.swmed.edu
> Subject: 	Tungsten carbide knives
> 
> You may expect me to know this
> 
> How frequently do you have to sharpen tungsten carbide knives.
> Yes, I know, how long is a piece of string!
> 
> I appreciate comments on types of tissue cut - soft, calcified, 
> horses' hooves, etc
> 
> How about using them in the cryostat for undecalcified bone?
> 
> All experiences gratefully received.
> Russ Allison, Wales
>