04-13-2018, 10:33 PM
Ok so finally got the right PH test strips, the dye test solution turned out to be 2 full PH points different to the vinegar essence used as the base (so 100x less acidic as I understand it).
Base Vinegar essence tested PH2(vinegar is usually shown as PH2 in charts)
Copporas/Vitriol/ Ferrous Sulphate solution (Vinegar essence with 25% acid + iron) after 6 weeks PH4
so it turns out that that mixture is much less acidic, about the level of tomato juice so I dont think this would be a problem in the long term on vegetable tanned leather... at least as far as acid damage is concerned.
So to recap you can produce a Black dye/stain for any Vegetable (tannic acid) tanned leather by adding a small amount of iron to a vinegar base, the stronger the acid concentration the quicker and more effective the response, ordinary household vinegar essence at 12.5-25% acid content works well, filter after 4 weeks maximum or use the solution up completly by that time, apply with a brush...
You can also test your leather with this solution to ensure that it is actually vegetable tanned if your unsure...
Vinegar by itself produces no response other then "water" staining...
Base Vinegar essence tested PH2(vinegar is usually shown as PH2 in charts)
Copporas/Vitriol/ Ferrous Sulphate solution (Vinegar essence with 25% acid + iron) after 6 weeks PH4
so it turns out that that mixture is much less acidic, about the level of tomato juice so I dont think this would be a problem in the long term on vegetable tanned leather... at least as far as acid damage is concerned.
So to recap you can produce a Black dye/stain for any Vegetable (tannic acid) tanned leather by adding a small amount of iron to a vinegar base, the stronger the acid concentration the quicker and more effective the response, ordinary household vinegar essence at 12.5-25% acid content works well, filter after 4 weeks maximum or use the solution up completly by that time, apply with a brush...
You can also test your leather with this solution to ensure that it is actually vegetable tanned if your unsure...
Vinegar by itself produces no response other then "water" staining...
Ivor
"And the four bare walls stand on the seashore. a wreck a skeleton a monument of that instability and vicissitude to which all things human are subject. Not a dwelling within sight, and the farm labourer, and curious traveller, are the only persons that ever visit the scene where once so many thousands were congregated." T.Lewin 1867
"And the four bare walls stand on the seashore. a wreck a skeleton a monument of that instability and vicissitude to which all things human are subject. Not a dwelling within sight, and the farm labourer, and curious traveller, are the only persons that ever visit the scene where once so many thousands were congregated." T.Lewin 1867
