Leica CM1950 manual Troubleshooting, Problems During Work, Problem Causes Remedies

9.Troubleshooting

9.1Problems During Work

Problem Causes Remedies

Frost on chamber walls and microtome

Cryostat is exposed to air currents (open windows and doors, air conditioning).

Frost built-up by breathing into the cryochamber.

Change place of installation for the cryostat.

Wear mouth protection.

Sections smear	Specimen not cold enough.
	Anti-roll plate not yet cold enough,
	thus warming the section.

Select lower temperature. Wait until knife and/or anti-roll plate have reached chamber temperature.

Sections splinter	Specimen too cold.	Select higher temperature.
Sections not properly	Static electricity/air currents.	Remove cause.
flattened	Specimen not cold enough.	Select lower temperature.
	Large area specimen.	Trim the specimen parallel,
		increase section thickness.
	Anti-roll plate poorly positioned.	Reposition anti-roll plate.
	Anti-roll plate poorly aligned with knife	Align correctly.
	edge.
	Incorrect clearance angle.	Set correct angle.
	Blunt knife.	Use different part of the knife.

Sections not properly flattened despite correct temperature and correctly aligned anti-roll plate

Dirt on knife and/or anti-roll plate. Edge of anti-roll plate damaged. Blunt knife.

Clean with dry cloth or brush. Replace anti-roll plate.

Use different part of the knife.

Sections curl on anti-roll	Anti-roll plate does not protrude far	Readjust correctly.
plate	enough beyond the knife edge.
Scraping noise during	Anti-roll plate protrudes too far beyond	Readjust correctly.
sectioning and specimen	the knife edge and is scraping against
return movement	the specimen.

48 Operating Manual V1.1 – 05/2007