This procedure/approach was developed because of problems that arose over time with the MFX slits movement. The identified issue was difficult movement by the M4 M3 slit (+X movement slit) that resulted in extreme vibrations of the entire unit, and the MDrive17 knob when turned by hand felt like it was clunking into place/there was a lot of resistance in comparison to the other turning knobs.
Consult with JJ X-Ray identified one potential issue that would not yield opening up the beamline: inside the unit each slit is mounted on a lead screw. The lead screw is connected to the motor externally to rotate by a magnetic double plate system (one vacuum side and one not). These plates could be assembled in such a way that the gasket between them is pinched or flexed. This would lead to rubbing between the magnetic plate and cause disrupt in the movement of the slit. This would be the first way to approach the problem because it only requires venting the beamline. IF THIS IS NOT THE SOLUTION: you will have to open the entire beamline and remove the slit apparatus.
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- Vent the beamline according to protocol (keeping in mind PRVs at the source and point of use, this will require a lot of nitrogen so plan ahead)
- Open the slit apparatus at the motor flange
- The motor is screwed to the flange from screws internally, so you will open up the top cover exposing the brain then find long internal screws to remove the motor itself from the flange. After that you will remove the flange from the six screws holding it into place. (THIS IS IF YOU WANT TO OBSERVE EXTERNALLY) The attached photo is what the flange looks like from the vacuum side with the special designed gasket removed to check for any of the interference that might have been occurring. No damage was assessed on our end, but there could be so check this area before proceeding to more drastic measures.
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