My first plastic vacuum chamber for evacuating rubber Moldavia never held much pressure. For this attempt, I poked around at the local thrift store and ultimately came away with a pot and a tempered glass lid that will enable me to see what is going on inside.
Until I got hold of it, there was absolutely nothing wrong with this pot; I’m certain it had a bright future of gumbo and jambalaya ahead of it. Sadly, I’m the only one in my household who appreciates Creole cuisine and so vacuum chamber it is!
It quickly developed a 3/4 inch hole and herniated a tubing connector. Unfortunately when the Boy and I soap-tested the pressure, we found the seam on the lid bubbles like a bean eater in a bathtub. However a gasket should resolve that and so we still believe that there is hope for this little pot.
Pembroke:87 
Try getting gasket in a tube from an automotive store. Should work like a charm. The beans are another problem.
Oh! I hadn’t heard of gasket in a tube. Thanks Neil.
what’s it for?
Making molds for casting resin.