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Hi everyone, I am commencing a few initial experiments with vinegaroon, and I wondered if anyone had any experience with a few ideas The darkening process of vinegaroon, as I understand it, is due to the reaction between iron (II and III) acetates and the tannic acid in vegtan leather. the role of vinegar is simply to dissolve the iron into a solution of ferric and ferrous acetate salts. If this is the case, it should be possible to pre-neutralize the vinegaroon using either baking soda or perhaps hydrogen peroxide (potential side formation of insoluble iron carbonate and iron hydroxide precipitates should be easily removed by filtering, and should not remove too much iron acetate before neutralizing the solution as long as most of the remaining acetic acid has already reacted with iron. A pH meter or universal indicator paper could be used to gradually titrate the solution towards neutral before using to dye leather This pre-neutralized vinegaroon should not overly acidify the already acidic leather, removing the need for a baking soda bath and avoiding the problems with potentially over alkalizing the leather. There is perhaps an increased potential for the solution to go mouldy over time (although the high concentration of iron salts should probably prevent this) but if this were a problem small amounts of vinegaroon could be neutralised before use, leaving the bulk solution acidic for storage until needed. As an initial experiment I pre-mixed a small amount of fresh vinegaroon (on the day I made it) with excess baking soda until the result was definitely alkaline (in fact the result was a paste with unreacted baking soda) and it still dyed the leather black. I have no doubt I over alkalized the leather in the process, but the point was to confirm that the acidic conditions of the vinegaroon are not necessary for the reaction with the tannins. I have a batch of vinegaroon maturing and have ordered a pH meter and some indicator paper, and plan to experiment properly in a few weeks, but am wondering if anyone has conducted similar experiments or can comment on my understanding of the chemistry. Also, if anyone has an idea of a potential base to neutralize the solution which won't precipitate out some of the iron ions, I would be interested. My hope is that pre-nautralised vinegaroon could be simply be rinsed off, leaving a dyed item that should not corrode metal hardware like snaps and rivets