Is it possible to have your PH too low and if it is will this cause slippage? I know that the PH is supposed to be kept below 2, will keeping it in the 1.30 range have adverse affects on the tanning process? I would appreciate any info on keeping the PH below 1.50. I looked in the archives and didn't see any solid information on a low PH. Thanks for the help.-------TED
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On searching for pH on the forums. The only thing it may do is acid burn the hide and hair. Almost every post on pH refers to under 3.0, plus several post on storing hides long term at pH of under 3.0.
www.hidetanning.net may help you also.
You should be fine just like Sarah said.
When pickling - low is always good. If you also use 1 Lb. of Salt/1 Gallon of Water - the Salt will prevent any damage from the Acid. Almost all Acids work between a 0.05-3.00 PH Range - but each one has it's "bottoming out" PH level. In other words - no matter how much acid you use it wont go any lower than its bottoming out level.
Saftee Acid is a good example. If you mix it up .5 fl. ozs. and 1 Lb. of salt to each 1 gallon of water - it usually measures a 1.1 PH. Then after placing the skins in - it may move up to a 1.5 PH. This is still a good range as you want it below a 2.0 where all bacteria are killed and you actually sterilize the skin.
If you add more than .5 fl. ozs. of Saftee Acid/1 gl. of water and salt - for example, maybe 3 fl. ozs. of it - the PH will probably not go lower than a 0.7 PH level. Again - as long as you have Salt with it - the salt will protect the skins. The worst that can happen is that the fur or hair may begin to "singe" (the ends begin to curl)!
I know that formic bottoms out around 2, but how about sulfuric and citric? Where do they bottom out?
Thanks to everyone who responded. I know that salt is a mandatory requirement in the tanning process. Yes I did add 1lb salt/gal H2O. I haven't seen any signs of acid burn to either the hair or the hide. The hide was suspect to start with, I was just trying to eliminate any and all possibilities other than the way the hide was handled before I got my hands on it. The low PH was the only thing I wasn't sure of. Everyone has eliminated that possibility. I am relatively new to the tanning game, but I do my homework on everything I do. I have had excellent results on everything else I have tanned. I have a few more tricks to try before I turn this hide into a piece of leather without the hair. Once again thanks to everyone. There is a lot of valuable information here if you do your homework. Thanks--------TED
Bruce, I found a close enough answer in a previous post:
This response submitted by Bruce Rittel on 09/20/2002. ( Rittel@mindspring.com ) 188.8.131.52
There are a lot of Acids which can be used for pickling! Sulphuric is one, Oxalic, Citric, Formic, Saftee, White Vinegar and even Hydrchloric acid has been used! But - they all have advantages and disadvantages to contend with.
Sulphuric, as has already been said, can be touchy to handle (it will definitely burn you) - personal safety-wise! It also, in my own experience, even though they use it a lot in the leather industry, does not plump the skins for shaving, as well as the other acids do! And then there is the old problem of over-sulponating the skin - which leads to eventual acid rot, unless you are tanning with a tanning agent that will "lock" in the sulphates!
Oxalic is a good pickling acid and relatively safe to handle because of its crystal form - however, it is a poison if ingested, so some care must be taken. It does however, plump better than Sulphuric. Skins should be left in it 3 days for maximum effect and a thorough pickling.
Citric Acid is also considered a safe acid, and very environmentally safe, as well as safe to handle. Its a good plumper also, but again, skins should be left for 3 days to get the maximum benefit from a thorough pickling. One of its drawbacks is that it is absorbed by the skins and the PH usually flucuates. This is particularly true on thickly fleshed skins. You have to use a lot of Citric acid to keep the PH down.
Formic and Saftee Acid win my recommendations for providing the best plump to a skin, so it can easily be shaved. Formic is a little faster pickling then Saftee. It usually only takes 2 days to thoroughly pickle with Formic, whereas with Saftee I'd leave my capes for 3 days in Saftee.
The biggest disadvantage of Formic is it can also burn you on contact like Sulphuric and a lot of care must be taken when handling it. It also will not drop your PH lower than a 2.0 - no matter how much acid you add. Thats its bottom level. This really isnt a problem - because it does pickle well at a 2.2-2.5 PH. Since you only need to use 0.9 fl. ozs. of it (85%) to each 1 gallon of Water - it is also economical. But buying it requires hazardous shipping.
Saftee Acid is environmentally safe and safe to handle - but with some caution. Its buffered so if you did handle it pure, you have 5-10 minutes to wash up without burning yourself - but beyond that - in its pure state it can eventually burn you. It's an acid. However, once its added to the pickle and diluted, it requires so little of it - only 0.5 fl. ozs. to each 1 gallon of water - that it is relatively safe. It pickles at a low PH of 1.1-1.5. Skins should be left in the pickle for 3 days to get the maximum effect.
White Vinegar is another safe pickling acid but it takes a lot of White Vinegar to keep the PH at a 2.2-2.5! Actually its the 6% Acetic Acid in it that does the pickling. Again - leave your skins in it for 3 days to gain a maximum plump.
Hyrochloric Acid is an extremely harsh acid to use. Muriatic Acid is simply the same thing in a diluted form. By harsh I am referring to the fact that it may weaken the epidermis. It is used to pickle Alligator and Croc skins because it weakens the cartilideous material in the hrnbacks - but for furs or hair-on - I prefer not to recommend it.