OCI BDL800IR, Instruction Manual

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56 Chapter 8 Maintenance
7. Use a blow gun (preferably compressed nitrogen) with a filter to gently clean the op-
tics’ insides.
8. Use a blow gun to clean the grids and mount them back in the right order. Do not for-
get to reconnect Screen, Grid#4, and Grid#2 connections.
9. Place the top mu-metal back in place and tighten the three (or four) screws.
10. Slide the cylindrical mu-metal back in place and tighten the two screws on the side.
8.2 Filament Replacement
The user should have the following tools before attempting to replace the filament:
 dust-free environment—a positive pressure blower with HEPA filter, a laminar
flow clean bench, or a clean room
 a pair of pliers or a vise grip
 tweezers or small pliers
 flat screwdriver (2–4 mm)

Allen key 5/32” or 4 mm
Before proceeding, make sure the optics is standing upright.
1. Unscrew and remove the shutter (if applicable).
2. Follow instructions provided in Section 8.1, items 1–5 (except cleaning the grids).
3. Disconnect the old filament (unplug female connectors).
4. Detach the electron gun by undoing the two screws.
The next 5 steps may be skipped if you are replacing a filament of the same type.
5. Electron gun connectors are different for LaB6 and thoriated tungsten filaments.
Therefore, they need to be swapped out. The optics needs to be slightly extended.