Filter
Top Products
4.1.1
4 - 3
CAUTION: The gun housing should be lifted by both hands until it stops. If the gun
housing is released halfway, your fingers might be caught in it.
NOTICE: Take care not to leave fingerprints on the internal vacuum parts for preventing gas
degassing. Be sure to wear clean gloves when performing the following procedure.
(5) Turn the holding ring counterclockwise to remove the cartridge filament assembly.
Fig. 4.1-5 Removing the Cartridge Filament Assembly
WARNING: When used, the filament becomes hot, reaching approximately 90℃. Therefore,
touching it carries the risk of burns.
For replacing a filament, let it stand for 30 minutes or more after air is
introduced, and work should be performed after the filament has cooled down
sufficiently.
(6) Remove the Wehnelt cylinder. If the Wehnelt cylinder hole is contaminated, clean it with
bamboo stick, absorbent cotton, polishing paste, acetone, etc. It is good practice to clean
Wehnelt at every filament change.
Fig. 4.1-6 Cartridge Filament Assembly
NOTICE: Any polishing paste used in the cleaning operation should be removed completely. If
a cartridge filament assembly with some residue still attached is used, the emission
current fluctuates and can cause a faulty image, such as changes in brightness.
Inspection with an optical microscope is a good way to check. Cleaning parts in an
ultrasonic cleaner is good practice.
Cartridge filament
Wehnel
t