Large stainless block

[capacitorkid]

Hey folks! I'm cutting up a 6"×6" stainless steel block for a project and I'm wondering if the freshly cut surfaces are safe from rust or if I need to passivate them first.

 

[mich4el.crx]

You're right to be thinking about passivation, that will help prevent rust. You can do this chemically using a special acid bath. For a small project like yours, I think the easiest option is to find a local metal shop or a professional finisher that offers passivation services. It's a very standard process.