Leica Biosystems CM1860/CM1860 UV - Manual (Page 57)

Leica CM1860/CM1860 UV – Cryostat 57
8. Troubleshooting
8.3 Possible sources of error, causes and remedies
Problem Cause Remedy
Frost on chamber walls and micro-
tome
- Cryostat is exposed to air cur-
rents (open windows and doors,
air conditioning).
- Sliding window was open and
exposed to air currents too long.
- Frost built up by breathing into
the cryochamber.
- Change place of installation
for the cryostat.
- Close the sliding window
correctly.
- Wear a mask if necessary.
Ice formation on the bottom of the
cryochamber
- Condensation water drain ob-
structed.
- Drain of the quick freeze shelf
defrosting water obstructed.
- Open the shut-off valve,
switch off the instrument and
let it thaw and dry.
- Leveling the instrument.
Sections bunch up at the blade
edge
- Specimen not cold enough.
- Knife and/or anti-roll plate not yet
cold enough - the section melts
as a result.
- Select lower temperature.
- Wait until knife and/or anti-
roll plate have reached cryo-
chamber temperature.
Sections splinter, cracks in the
section,
- Specimen too cold - Select higher temperature.
Sections not properly flattened - Static electricity/air currents.
- Specimen not cold enough.
- Large area specimen.
- Anti-roll plate poorly positioned.
- Anti-roll plate poorly aligned with
knife edge.
- Incorrect clearance angle.
- Knife/blade blunt or damaged.
- Eliminate cause.
- Select lower temperature.
- Trim the specimen parallel;
increase section thickness.
- Reposition anti-roll plate.
- Align correctly.
- Slightly increase knife/blade
angle.
- Use different part of the cut-
ting edge or replace.