Hi, My name is Rodrigo and I need to achieve a permanent seal for a vacuum chamber in the high vacuum range (I’ll be working between 1x10-4 and 1x10-torr). We were thinking of using a cold-weld sealing of an annealed copper tube to separate the chamber from the vacuum pump once the vacuum level is fine. I´ve already found one supplier of a reliable pinch-off tool that seems to do the job, but due to its high cost I need to find out more to be sure. Have anyone successfully use a pinch-of tool for a similar purpose, achieving high vacuum levels with no leak after pinch-off? I would appreciate very much if you tell me any specific product or tip! Thanks!