[3dem] Peculiar Glacios Issues

[Christopher Aylett]

Dear EM mailing lists,

We received our new Glacios from Thermo / FEI this summer, and initial commissioning proceeded extremely smoothly, however we have experienced several quite unusual and peculiar issues shortly after beginning user operation which I would like to run past the lists in case anyone has any insight into their possible underlying cause.

Autoloader issue (currently resolved by gripper arm replacement, but severe and of unconfirmed initial cause):

While the autoloader had been working perfectly during commissioning, following an initial initialisation error, the autoloader stopped registering clip-rings placed within it. Our facility manager was able to confirm that no grids or clip-rings had been dropped into either the column or autoloader itself, however there was clear mis-alignment (see attached video). We then had a series of more severe failures; the clip-rings were being bent into U-shapes apparently, although this was not through being pushed into the cassette, which was my initial assumption, as the dimensions do not match - some are too large, some too small. There does not appear to be any damage to our cassettes, so maybe the gripper jaws were clamping them down into this shape, although they should not open wide enough to allow that to the best of my understanding? I am still at a loss as to how this happened, and while it seems to have been resolved through replacement of the gripper arm by Thermo / FEI, I would like to find out what went wrong in the first place so that we can be certain it does not recur. I attach images in case they are helpful.

Drift issue (ongoing - intermittent and of variable severity):

While drift rates during commissioning were effectively zero (consistently below 0.2 Å/s with the stage at rest), we are now experiencing ongoing image drift which began suddenly shortly after commissioning completed, varies between 1 and 5 Å/s in rate, and is predominantly (but not exclusively) in the X direction, suggesting lens involvement. The drifting issue remains present despite one hour of stage rest. Our chiller was purchased from ATC rather than Thermal Exchange as is typical, however extensive monitoring of temperature has implied that both room temperature and chiller water temperature are stable within specification, and performance was admirable during commissioning. The drift appears to increase very distinctively once imaging commences e.g. a drift test begins, as can be seen in the attached drift test image, before plateauing. I have been assured that there has been no change in lens coolant flow / balance since installation, however.

Thermo / FEI have been responsive in fixing broken parts, and Paul - our facility manager - has been investigating matters, however we still lack explanations for either underlying issue. Should anybody have experienced similar issues with their own microscopes, or be able to provide probable diagnoses, we would be most grateful to hear from you - 

Best wishes,

Chris

#######################################







#######################################

Dr. C. H. S. Aylett

Principal Investigator and Sir Henry Dale Fellow
Imperial College London

#######################################

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0006.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: clipring_lineup.png
Type: image/png
Size: 2235070 bytes
Desc: not available
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0004.png>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0007.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: clipring_toolarge.png
Type: image/png
Size: 2298620 bytes
Desc: not available
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0005.png>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0008.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: clipring_toosmall.png
Type: image/png
Size: 2334976 bytes
Desc: not available
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0006.png>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0009.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: increasing_drift_test.png
Type: image/png
Size: 5682714 bytes
Desc: not available
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0007.png>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0010.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: autoloader_failure.mp4
Type: video/mp4
Size: 6140978 bytes
Desc: not available
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0001.mp4>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20210922/a0241f07/attachment-0011.html>