Leica Biosystems CM1950 - Manual (Page 52)

52 Instructions for Use V 1.5 - 08/2014
9. Troubleshooting
Problem Cause Remedy
Ridged sections Cryostat is exposed to air currents
(open windows and doors, air
conditioning).
Frost built-up by breathing into the
cryochamber.
Use different part of the knife.
Replace anti-roll plate.
Chatter during sectioning Specimen insufficiently frozen onto
the specimen disc.
Specimen disc not clamped tightly.
Knife not clamped tightly enough.
Specimen has been sectioned too
thickly and has detached from disc.
Very hard, inhomogenous specimen.
Blunt knife.
Knife profile inappropriate for
specimen cut.
Incorrect clearance angle.
Refreeze specimen onto the disc.
Check disc clamping.
Check knife clamping.
Refreeze specimen onto the disc.
Increase section thickness; reduce
specimen surface area if necessary.
Use different part of the knife.
Use knife with different profile.
Set correct angle.
Condensation on anti-roll
plate and knife during
cleaning
Brush, forceps and/or cloth too warm. Store all tools on storage shelf in the
cryochamber.
Anti-roll plate damaged
after adjustment
Anti-roll plate too high above the knife
edge. The adjustment was carried out
in the direction of the cutting edge.
Replace anti-roll plate.
Be more careful next time!
Thick/thin sections Temperature incorrect for the tissue
cut.
Knife profile inappropriate for the
specimen cut.
Ice buildup on the knife back.
Handwheel speed not uniform or
turned at incorrect speed.
Knife not clamped tightly enough.
Specimen disc not clamped tightly
enough.
Cryocompound applied to cold
specimen disc; specimen detached
from disc after freezing.
Select correct temperature.
Use knife with different profile (c or d).
Remove ice.
Adapt speed.
Check knife clamping.
Check disc clamping.
Apply cryocompound to warm disc,
mount specimen and freeze.