Re: Rae Staskiewcz - Re microm Microtome

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Please be sure to check with your sales rep before you make any adjustments
like this:

In a message dated 2/15/99 9:31:14 AM Eastern Standard Time,

<< Rae -  I have two microm automatics, and just love them.  The problem that
you are having may be the knife holder.  I have found that these holders are
very easily damaged, and even the smallest imperfection in the clamping
surface will cause a vibration problem.  This is because, an imperfection will
cause the blade to be clamped tightly in one spot, but not the rest of the
blade, so it permits the blade to vibrate.  I have a small machinest dressing
file, about 5 inches long that I use to dress the imperfections out of both
the lower clamping surface and the upper clamping surface. Quite often, when
you run the file across these surfaces you will immediately see that it is
removing very small amounts of metal in only one spot. Dress the holder down
untll the entire surface shows new dressing marks.
 There is a second problem that I had with one of my units that is a little
more difficult to detect.  With this unit the upper clamping plate  griped the
blade about 1/2 way down, instead of at the upper most portion.  Again this
let the blade vibrate when cutting any thing but the softest of tissues.   To
determin if this is the problem, you can try to observe the clamping plate and
knife end on, to see if the clamping plate is in fact clamping the blade at
its upper most edge.  Or, you can use some very thin feeler gauges ( 0.01 -
0.02 ) to see if you have a clearance problem, or in my case I had to revert
to some machinests blueing which I painted on the underside of the upper
clamping plate, then clamped a blade in the holder. The blueing transfers onto
the blade, and shows you exactly where the pressure points of the clamp are.
If this is the problem, then you have to have the clamping plate reconfigured,
( I simply filed mine ) untill it clamps the blade properly, which is along
the upper most portion of the the clamping plate as close to the cutting edge
of the blade as possible.  On more thing, with these units (and using feather
blades) I have found that they seam to cut best when the holder is showing 13
degrees of  knife angle.
 Hope this is of some help.
 Kerry Beebe
 Kelowna Gen Hospital
 Kelowna B.C. Canada


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