Actually guys all metal will rust, give it time and it will all rust.

 

to not get into anything too complex for an explaination for why stainless in your exhaust rusts, put simply, the properties of stainless are changed as you constantly heat it and let it cool naturally, which results in the structure and distribution of the elements in the alloy changing. typically stainless has a higher concentration of chromium oxide on the surface that prevents rust, but as you heat and cool it, the iron in the alloy diffuses to a higher concentration at the surface where it gets exposed to oxygen and beings to oxidize or rust. there's a lot of cool things that happen when you heat and cool metals, diffusion of alloyed elements is one of them, and it can be an interesting topic

actually in terms of actual "rust" which refers to iron oxide, not all metals "rust", every metal will oxidize however, including aluminum. in fact, most aluminum you get for your car is anodized or pre-oxidized, as pure raw aluminum is hard to come by, and on the microscopic level, there's always a film of alumina on the surface of any aluminum that's been exposed to oxygen or air

with traditional hot-dip galvanizing, you can't galvanize just one surface of a pipe, you'd galvanize both the inside and outside of the pipe, as it involves dipping steel in a hot bath of zinc, which forms a layer of zinc and zinc-iron alloys on the surface, zinc being used as a sacrificial material to oxidize first (zinc forms zinc-oxide easier than iron forms iron-oxide). galvanization by electroplating can yield single side coatings, but is not traditionally used in galvanization of pipes or low cost materials (electroplating costs more). typically galvanization by electrodeposition is used as a step in the process of chroming metals. a zinc layer is used to fill imperfections in the base material and to provide a good surface for the deposition of chromium. in order to form a layer on only one side, the material has to be insulated from the zinc bath. this can be done in several ways. the galvanizing process is similar to anodization in purpose, but slightly different in methods and chemical results.

 

^ Haven't had a chance to say it, but welcome to the forum cderalow. You look like a great addition.

And cool build sniper, gave me some more ideas for mine.

 

thanks...

funny since graduation college, i've only called upon the stuff i learned in school twice... both on account of this forum, and never during my day job

 

nice setup sniper, very ghetto but its functional. i am going to use aluminized steel for my downpipe and dumptube because it is cheaper than stainless and will last longer than stainless. the only thing stainless is good for is the bling bling look.