Tony,
Stainless is strange stuff with regards to corrosion. Some avenues of thought regarding your phenomeon are the difference between active and passive stainless-perhaps an acid wash before applying the resist could change things--or crevice corrosion in stainless, where the corrosion attacks only in cracks or other oxy starved places. This is usually solved by using a different stainless alloy or different corrosive media. Good luck
Chuck Nafziger
