Jon, Cao

Today we raised the height of the shelf overhanging the cleanroom laser table by 8 inches. This was done to create more vertical clearance between the top-loading vacuum chamber and the bottom of the shelf. The added clearance should make both removing the chamber lid and inserting large parts easier.

The procedure required unmounting the shelf and removing all eight vertical support posts (1" x 1" x 18.5" pieces of 80/20 unistrut). The support posts were taken to the machine shop and cut, retapped, and cleaned (coarsely, with IPA wipes) prior to reinstallation. We took care to minimize the contamination introduced into the cleanroom, but some amount of particulate from disturbing the shelf was unavoidable.

This work is completed, and the cleanroom is now ready for final cleaning (HEPA vac, mopping, and wiping down of all surfaces including the softwalls).