Tools Required:

Procedure

The following procedure applies to the removal of the blue grisms on LRIS.
  1. Select LIRS Engineering -> Changouts -> GRISM to service port from the instrument desktop menu. Launches the GRISLOAD gui.
  2. On the "GRISLOAD" gui select desired port and click SET. This will move the desired grism to the service port.
  3. Rotate LRIS to the fill position so that the grism carousel is at the top of the instrument. This will make it much easier to load and unload the grism.
  4. Climb on top of the instrument and locate the carousel.
  5. Pull the tethered T-handle pin which locks the load door in place. Note: The pin is an interlock for the carousel!
  6. Open the load door.
  7. Screw in the palm-grip handle. This allows you to lift out the filter, and also locks down the latching mechanism to the cell assembly.
  8. The holder is kept in place using 3 or 4 screws which secure the optic cell around the edge of the plate. Use a 7/64 allen head wrench to loosen these captive screws until they rattle.
  9. Carefully lift the grism out of the carousel.
  10. Place the grism to be serviced in its storage case or cart.
  11. Remove the palm-grip handle from the grism.
  12. Close the load door.
  13. If removing more than one grism, repeat steps 3 thru 12.
  14. Insert the tethered T-handle which locks the load door in place.

Pictures with the 7/64 T handle in one of the four retaining screws and the palm handle inserted.