Waters GCT Premier Operator's Manual page 250

Securing screws
Hex-head screw
8. Unscrew and remove the four screws that secure the front support plate
to the metal rods.
9. Remove the front support plate.
10. Remove each lens plate and its associated spacers from the outer source
assembly in turn.
Tip: The outer source comprises the various lens plates held in place by
four ceramic rods, one at each corner. Between each lens plate are metal
or ceramic spacers of different sizes. To aid reassembly, record on a
diagram the order, position, and orientation of each lens and each spacer
on its rod. as you dismantle the source.On some layers, the spacers on
the upper rods differ from those on the lower rods.
Alternative:
outer source lid assembly, avoiding the need to remove the washers and
the spacers around the inner source contacts.
To clean the focus lenses:
1. Rub each side, and the inner aperture, of each lens plate with
1200-grade wet/dry paper to remove any visible ion burn.
Requirement:
10-46 Routine Maintenance
Front support plate
You can also access the lenses from the opposite end of the
The inner aperture of each lens plate must be cleaned.
Outer
source lid