Pickling acid

I’d better rush out to get some H2SO4 before it unobtainable....

**LINK**

Better take my safety specs and arm length rubber gloves - this stuff is 91% conc. it sez on the label.🙂

John

Multiple posting - again! Please ignore. 😳

Edited By Johnboy25 on 09/04/2018 15:55:37

So what's wrong with Dry salts then as an alternative.

I suspect that Sulphuric acid (diluted from concentrated) was always used because of it's availability rather than it's efficacy. GLR have been selling dry salts for years as it's simpler and safer to ship.

regards Martin

That rather depends on what you mean by 'Dry Salts.

Assuming you mean GLR kennions I can only find Dry Acid Pickling Crystals.

A toatlly unsatisfactory description. No indication of what acid or concentration. It may contain substances not complying with REACH. Who can tell?

copied from a post in 2009

Edited By duncan webster on 10/04/2018 00:12:45

Edited By duncan webster on 10/04/2018 00:13:09

It also means the ban in effect of home or cottage industry blacking, plating, anodising etc without appropriate licence.
Tried getting a explosives licence, forget it.

We can probably manage with 15%.

Rod

I come from a jewellery making background and for many years have used "safety pickle" in place of sulphuric acid. It's not quite as effective as the "unsafe" alternative, no, but when used at the right concentration and heated in a slow cooker or dedicated "pickle pot" it is still very effective at removing flux residues and oxidation from brass, bronze, copper, silver and gold after brazing. One bonus besides the safety is it isn't so effective at leaving holes in your carpets and clothing when it splashes where it shouldn't.

I use phosphoric acid. It works well and I can buy it from a hardware store in Australia. Not sure what it's intended use is but I think it is used for rust prevention too.

NaHSO4 works well if you keep it warm, but that means leaving the power on in the workshop all night which im not keen on, when it cools it forms a crystaline structure in the bottom of the tank.

I note that there is no suphuric acid for sale on ebay but battery acid (which is sulphuric) is, at 31% to 37%.

Amazon seem to be happy to sell sulphuric though.

I've always used about 10% because it is not too aggressive.

Brian