Take a look at this picture:
Yes I am hacksawing a dilution refrigerator….
One of the entry ports to the IVC has been hardsoldered with a stainless steel placeholder bush. We need to replace this with our custom made copper bush with feedthroughs for coaxes and DC lines. It is virtually impossible to remove this part given the small space around it, and we decided that we don’t want to put power tools nearby, lest we accidentally buzz through the dilution unit. Which would be a bit like putting a scalpel through the jugular.
So hacksaw it is.
I wonder how many low temperature physicists have wanted to saw their dilution fridges in half before. Today I got to indulge in that pleasure. The results weren’t pretty at times:
Although half way through I started thinking ‘I hope that this is the right part I’m sawing…’