Leica CM1950 manual Cryochamber

		9. Troubleshooting
Problem	Causes	Remedies
Ridged sections	Knife damaged.	Use different part of the knife.
	Edge of anti-roll plate damaged.	Replace anti-roll plate.
Chatter during sectioning	Specimen insufficiently frozen onto	Refreeze specimen onto the disc.
	the specimen disc.
	Specimen disc not clamped tightly.	Check disc clamping.
	Knife not clamped tightly enough.	Check knife clamping.
	Specimen has been sectioned too	Refreeze specimen onto the disc.
	thickly and has detached from disc.
	Very hard, inhomogenous specimen.	Increase section thickness; reduce
		specimen surface area if ecessary.
	Blunt knife.	Use different part of the knife.
	Knife profile inappropriate for	Use knife with different profile.
	specimen cut.
	Incorrect clearance angle.	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	Anti-roll plate too high above the knife	Replace anti-roll plate.
after adjustment	edge. The adjustment was carried out	Be more careful next time!
	in the direction of the knife.
Thick-thin sections	Temperature incorrect for the	Select correct temperature.
	tissue cut.
	Knife profile inappropriate for the	Use knife with different profile
	specimen cut.	(c or d).
	Ice buildup on the knife back.	Remove ice.
	Handwheel speed not uniform.	Adapt speed.
	Knife not clamped tightly enough.	Check knife clamping.
	Specimen disc not clamped tightly	Check disc clamping.
	enough.
	Cryocompound applied to cold	Apply cryocompound to warm disc,
	specimen disc; specimen detached	mount specimen and freeze.
	from disc after freezing.

Leica CM1950 Cryostat 49