Hello all,

I developed a method when I worked at the University
of Chicago that helped me create nice thick sections
in the 40-50 micron range.  I wish I could show a
video of it because it's hard to demonstrate using
words.

1. Get a ribbed back razor blade. (The kind you can
get at the hardware store) Many E.M. labs use these
for cutting kidney bx's. Put enough tape over the
sharp edge to protect yourself from cuts because you
are going to use the opposite end. (The steel ribbed
back surface)

2.Face off your block. (Thick trim)

3.Place the steel edge flat across the block at a
downward facing angle. (Basically a mirror image of
the knife angle used to cut the block)

4.Applying a small uniform amount of pressure with the
blade's steel back, turn the flywheel on the tome very
slow and steady and the section will slide right out
under the steel edge onto the knife. It shouldn't be
very far above the knife either. (Less than 1 mm)

It will take some practice, but it works nicely.

I also found using this method, that I never had to
ice the block (whether brain or routine) and that my
skill in using an anti-roll device in the cryostat
came in handy for this skill because there is a
certain pressure you have to apply to get the section
to come off correctly.

Hope this is clearer than mud!

Scott Taft HT(ASCP)
Ventana/Tucson AZ

--- Maureen Decorah <decorah@rarc.wisc.edu> wrote:
> Received this question but I don't have any
> experience cutting this thick.
> Does anyone have suggestions for him?
> 
> 
> 
>  I am trying to cut 40 micron sections of brain
> tissue (mouse)
> >embedded in paraffin.  The sections don't come off
> the knife well and if I
> >do get them they crack later.  I seem to be able to
> get 5 micron sections
> >from the same block ok.  Is it possible to get 40
> micron sections and if so
> >are there any "tricks" to doing it?  Thanks again
> for your help.
> >
> 
> 
> 
> 
>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 	Maureen Decorah, Research Animal Resources Center
> 	385A Enzyme Institute, 1710 University Avenue
> 	University of Wisconsin - Madison, Madison, WI
> 53705-4098
> 	(608) 262-0933  Fax(608) 265-2698  E-mail:
> decorah@rarc.wisc.edu
> 
>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> 
> 
> 

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