... Some info would help before i burn some drills and break some taps with stainless. Thanks
If you decide to go with SS, which is a Much better choice of material, you might look into "Four Hundred Series" Stainless verses "Three Hundred Series".
4xx SS has most of the Corrosion resistance properties as 3xx but is easier to machine/drill/tap.
3xx SS isn't the easiest thing to machine but it is doable. Just have to dial in your Speeds & Feeds a lot closer than something like Alum.
Also when it comes to tapping a Hard Alloy, consider using less Thread Height like 68% when you choose your drill size. The thread won't have as much Strength as a one with more Thread Height but Ultimate Strength isn't that important in an e-Cig mod.
Fundamental Rule in the Machine Shop: The Bigger the Drill used to establish the Minor Diameter of an Internal Thread, the Easier it is to Tap the Thread.