Stainless pickling/passivating

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Saw a new (to me) product in the last AWS journal... http://derustit.com/products/wonder_gel.phpAnyone ever use this before?  We have been using an acid wash of sorts to remove heat marks and oxidization on stainless parts but this seems like it would be a better alternative.Have we all gone mad?
Reply:From the MSDS sheet in the link it's just a different brand of pickling paste, all the common flavours contain nitric and hydrofluoric acid, the stronger/quicker ones typically containing a little more HF acid than that blend. Avesta have a huge range of different flavours/strengths. The acid wash you currently use... is that not similar/same blend of acids just not in paste form? Or are you using electrochemical weld cleaning? More detail on pickling and passivation of stainless here. A very good idea to have calcium gluconate gel or avesta 910 spray to hand if there's even a remote possibilty of getting splashed by something with hydrofluroic acid in it
Reply:hotrodder, I didn't even know the electro clean/polish was still out there. The selective cleaning/polishing I knew had no equal, the sad thing is all the job shops I knew that selective plated (also electrocleaned) dropped it (EPA stuff).The even sadder thing is that with passivation no acid was used if I remember right.Matt
Reply:My bad manners sn0, I didn't mean to hijack your thread with the above post. I haven't any knowledge of derustit products.Matt
Reply:We are currently using electrochemical cleaning, I cant think of the brand of acid off hand but it does do a good job in most spots.  I was more or less looking at this as something to fit in tight corners or doing long straight seams.Have we all gone mad?
Reply:Right, with you now Sn0wborder. As you say the 'wands' with those electrolytic weld cleaning machines aren't great when it comes to nooks and crannies. The electrolytic cleaners... way i understand cleaning solutions/acids vary in strength with brands as does machine power just like there are different strengths of pickling pastes. Some of the cleaning solutions i'm aware of are phosphoric acid based, others citric. I've used battery chargers and citric to passivate stainless before but really need more power than you get from typical battery chargerWeaker/less toxic pastes tend to struggle with burnt welds or take a lot longer but at least the stuff can be applied and then just left. The stronger/faster ones tend to leave a 'tide mark' or a 'halo' around the treated area, are pretty pungent and need treating with a lot of respect. They will however deal with burnt weldsRecently heard about about some developments with the electrolytic kit in that they are now available with brushes instead of the solid wands. Might be the way forward if your kit is compatible power/chemical wise...Matt, i'm in the UK so environmental side is no doubt quite different. Health and safety nazis would rather electo chemical methods are used over traditional pickling acids and would prefer citric based solutions are used for passivation over traditional nitric solutionsWaste/rinse water from both processes contain metals and other nasties even after neutralisation so don't really get the environmental arguments although there's no doubt more to it than i'm aware of
Reply:Wow, I would love to get my hands on that brush.  I wonder how it conducts the current without arcing out or melting the strands.Have we all gone mad?