Maintenance for Horizontal Gas Flow Cryostat 2

Kapton window was leaking helium to vacuum space. The window was original window and the edges were coming off.! It was replaced with a 0.003" thick kapton window cut to size. Both surfaces were cleaned and scratched with 120 grit sand paper. Oxford expoy was used in 1 to 2 ratio ( 1 part hardner). Mixed for 5 min, rest for 10 min and applied; one hour work time, 24 hours cure time.

Leak checked after 2 days and cooled down after a week. It's better to cycle the cryostat few times when cooling with helium, sometime it doesn't leak after first time!