Here is my new personal development: a small stainless steel weld cleaning setup. First of all, I was not happy with pickling and passivating pastes - they are poisonous and highly toxic. Require a high level of safety and very dangerous to handle and use, messy and very difficult to wash and the main thing I did not want this sh... stuff anywhere on my alcohol stills and stills of my customers, anywhere near my workshop and myself personally.
In fact, there are some different nontoxic methods exist: sandblasting, mechanical polishing, and electropolishing. So the sandblasting is ok but can ruin the mirror finish. Sandblasting requires the special enclosed chamber, compressor and heaps of other stuff. I use it, but for some little spots, the next one is a mechanical polishing, again - not good for difficult to reach places, can be messy and limited by the shape of the detail - I use it too, for easy to reach things, but what about electropolishing? First of all, it is gives a lot of advantages over chemical passivation - not messy, nontoxic, easy to wash off.
The setup utilizes a method of electro-galvanic metal cleaning where electricity, electrolyte, and electrical conductors are involved. The readily available installations for electropolishing are selling commercially, though quite expensive. So I done my research and experimenting, and found that many things are readily available and cost next to nothing in comparison with a commercial setups, plus I am in the stainless fabrication industry, and I found that the most of the things that I need already available in my workshop, also I am making my carbon brushes myself.
The insulated brush holder cost a few dollars to build, and non-toxic chemicals are available in local automotive parts shop, thus if you about to create your stainless steel based distillation equipment, you may consider using this simple DIY electropolishing method to make your equipment bright and shiny and free of poisonous traces.