Alot of good info here but stay away from N2
(nitrogen) unless you have experince, it is dangerous.Not only can you really screw up yourself but you can also damage the part.
We used to use N2 to freeze fit stainless steel valve seats into valves for liquid oxygen plants used to make air for fighter pilots. drop an apple or quarter into the N2 then pull it out with tongs and throw it on the deck, it shatters like glass. Big fun
until the Chief caught us, same with using
freon or CO2.
Non, je ne regrette rien.