28% acetic acid?

[Ed Pierce]

I'd like to try and make some F6 odorless acid hardening fixer. I can't get glacial acetic acid locally and don't want to pay hazmat shipping charges.

Is Kodak Indicator stop bath the same thing as 28% acetic acid?

[Robert A. Zeichner]

Indicator stop bath has other stuff in it that initially makes the stop bath orange in color, but that turns bluish when close to exhaustion. I've always avoided it. 28% acetic acid is not glacial acetic acid, but rather a dilution of it. You can make 28% acetic acid by diluting glacial acetic acid 3 parts GAA to 8 parts water, but you can't go backwards. If 28% acetic acid is what you really need, you might be able to order that without paying the Hazmat fee. If I'm not mistaken, there is a camera shop in White River Junction that has darkroom chemicals. You might call them to see what they have on the shelf.

[percepts]

28% is one of the magic numbers that comes about because of the manufacturing process of acetic acid. It is not a photographic requirement critical to have it at 28%. I use 25% as its much easier to do quick mental calculations for volumes.

Agfa used to sell 60% acetic acid in 5 litres bottles which could be diluted down with water to 25% to use as stock. They stopped selling it now.

The good news is that all mini labs use aceteic acid in their processors and Fuji sell them 5 litre bottles of 60% acetic acid. So if you can get your local mini lab to get you one of those, then you'll have plenty. Its cheap and you can dilute it down to whatever percentage you like. No indicator in it.

[SamReeves]

Be sure to mix your glacial outside. It's extremely caustic. I usually go 112 oz water with 16 oz glacial. That ought to make a good stop bath with no yeller.

[Marko]

Be sure to mix your glacial outside. It's extremely caustic.

Actually, no, it's exactly the opposite...

[tgtaylor]

To use as a photographic stop, Kodak says to mix 2 ozs of acid with 1 gallon of water i.e., 1:64, or one ounce to 64 ozs (half gallon) of water which results in a 1.56% solution. A 28% solution is way too strong.

[percepts]

To use as a photographic stop, Kodak says to mix 2 ozs of acid with 1 gallon of water i.e., 1:64, or one ounce to 64 ozs (half gallon) of water which results in a 1.56% solution. A 28% solution is way too strong.

Methinks 28% is the oft quoted stock solution percentage and not the working solution percentage which is around 1.5% as you say. But you wouldn't mix stock as a 1.5% solution.

[cowanw]

Table vinegar is typically around 5%
Regards
Bill

[Jim Ewins]

Glacial Acetic Acid has a very high freezing point - so keep it at room temp if you wish to dilute.

[tgtaylor]

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Originally Posted by SamReeves
Be sure to mix your glacial outside. It's extremely caustic.

Actually, no, it's exactly the opposite...
__________________
There are only 10 kinds of people - those who understand binary and those who don't.

Actually, no, it's exactly the opposite...

WRONG!!! Acetic acid IS caustic. Check the warning notice on the label: "...Causes severe skin and eys burns..."