you can brush it alone with a stainless steel brush that only have done stainless.
or you can apply a treatment (some kind of acid)to clean the weld and at the same time, it help against rust.
we use a product that it call INOX CLEAN ( bio circle), with this product , we remove some discoloration and after that , we brush it .
when you ship your product , take a good care to not make the stainless come in contact with steel ( ex: fork lift, steel straping). If it happen , they may have chance of local rust at the contact zone . You can apply a treatment with a dedicated product to prevent rust to build up.
when stainless is use in the industrie , some kind of treatment is overkill but in your situation where the stainless must stay nice and clean , I belive the treatment will help.
Kevin, not sure if this is a viable option for a one off use or if you'd get your money out of it, but the Capital Weld Cleaners make cleaning stainless an afterthought. You can see their stuff at https://www.capitalweldcleaners.com/
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