Kodak Hardening Fixer hard to find. Alternatives?

[DoctorMikeReddy]

I’ve struggled to find anywhere with stock of Kodak Sodium Hardening Fixer Powder 3.8L. The two stockists I found online both cancelled the order, and their web does then reverted to “out of stock” so it seems no one has it. Why is it so elusive? What alternatives are there?

I’m wanting it for dry plate work with liquid light emulation using a reversal process like you get with the Rockland Tintype Parlour Kit.

 

[DoctorMikeReddy]

Ahah! Several threads about Kodak chemistry supply; inc. good news of a new supplier as of December 2023, but nothing tangible. So, I guess I need the alternatives, or what additives to get the same result

 

[mshchem]

This doesn't surprise me. Hardening fixers are rarely used today. Ilford Hypam can have hardener added. I would check with Ilford or Adox.
If you want to mix your own, Kodak F-5 fixer formula is published. Very easy to prepare.

 

[mshchem]

Old Kodak formulary has a hardener bath, dissolve 30 grams of potassium chrome alum in 1 liter. Harden plates for 4-5 minutes. Chromium salts aren't used anymore.

If you can find Kodak Rapid Fixer with Hardener that's what I use when I need a hardening fixer.

 

[DoctorMikeReddy]

Old Kodak formulary has a hardener bath, dissolve 30 grams of potassium chrome alum in 1 liter. Harden plates for 4-5 minutes. Chromium salts aren't used anymore.

If you can find Kodak Rapid Fixer with Hardener that's what I use when I need a hardening fixer.

I’ve found one place that (apparently) has stock of Rapid Fixer. We’ll see. My worry with the ‘rapid’ version is Rockland state (on their FAQ page at https://www.rockaloid.com/faq#15

“We recommend Kodak Fixer because (1) it hardens the emulsion more effectively than any fixer we have tested and (2) because it is non-fading, unlike some "rapid" fixers that will dissolve away part of the image while they work.”

 

[koraks]

Welcome to Photrio @DoctorMikeReddy !

The fading issue is a bit mysterious; in general a rapid fixer won't fade a silver image in a silver gelatin emulsion. In some particularly sensitive 'alternative' printing processes (Kallitype, Van Dyke brown, salted paper) this is known to happen and I'm surprised to read about it in the context of a silver-gelatin emulsion. Btw, using the fixer in a higher dilution than normal (1+20 or so) generally helps.

If hardening is desired, it's possible to use a separate hardener, which can be anything that hardens gelatin - think of chrome alum (which is not related to the nasty hexavalent chromium!) or potassium alum in an acidic solution. The latter is the hardening agent used in Kodak hardening fixers. The former, chrome alum, is generally more effective and very quick and it's what I would personally use.

In conjunction with the separate hardener, you could use any rapid fixer of your preference. If the silver image in these emulsions is particularly sensitive (generally you notice this as the emulsion is very slow to expose and yields a decidedly warm-toned/brown image), I'd be inclined to try a pH neutral fixer. A color fixer intended for C41 film would be my choice, but that's mostly because that's virtually the only fixer I use anyway (it works for literally everything!)

If a rapid fixer is truly anathema, there's always the possibility to mix your own non-rapid "plain hypo" fixer by dissolving some sodium thiosulfate in water. Sodium thiosulfate is cheap and generally easy to obtain in the pool section of your local hardware store, at least in the US and also here in mainland Europe. This is because it's used as a dechlorinating compound in pools (it's non-toxic). If you want your self-made fixer to be hardening, add a little chrome alum, or some potassium alum and some vinegar or citric acid. There's a formula you might use here: https://www.digitaltruth.com/data/formula.php?FormulaID=197 It's conceptually similar to Kodak hardening non-rapid fixer. Instead of the 28% acetic acid, you could use 7-8% acetic acid (a.k.a. cleaning vinegar; use an unscented variant, which tends to be the cheapest variant on sale) and adjust the quantity; just use 4x as much - although it's entirely non-critical and substituting the cleaning vinegar for the 28% acetic acid will most likely work like that, too.

 

[mshchem]

Potassium chrome (III) alum can be found on Ebay. This was used in the old E-1, E-3, Ektachrome processing kits back in the early days. It's a beautiful purple crystal, it's still a heavy metal so it should be cared for.

There's got to be someone in the UK who can supply you with what you are after. Either ordinary Kodak type powder or a separate hardener.

 

[Doremus Scudder]

Mix it yourself!​

​

Kodak Fixing Bath F-5​

For Films, Plates, and Papers

The Kodak Fixing Bath F-5 has the advantage over the older type of fixing baths, which do not contain boric acid, that it gives much better hardening and has less tendency to precipitate a sludge of aluminum sulfite.

In warm weather and in inadequately ventilated darkrooms the odor of sulfur dioxide given off by the Kodak Fixing Bath F-5 may be objectionable. This can be eliminated almost entirely by omitting the boric acid and subsituting twice its weight in Kodalk. This modification is know as Kodak Fixing Bath F-6.

Water, about 50 Celsius (125° F.) --- 600 ml
Sodium Thiosulfate Hypo) --------- 240.0 g
Sodium Sulfite, desiccated --------- 15.0 g
* Acetic Acid, 28% ------------------ 48.0 ml (see below)
** Boric Acid, crystals ---------------- 7.5 g
Potassium Alum --------------------- 15.0 g
Cold water to make ----------------- 1 liter

* To make approximately 28% acetic acid from glacial acetic acid, dilute three parts of glacial acetic acid with eight parts of water.
**Crystalline boric acid should be used as specified. Powdered boric acid dissolves only with great difficulty, and its use should be avoided.
Films or plates should be fixed properly in 10 to 20 minutes in a freshly prepared bath. The bath need not be discarded until the fixing time becomes excessive, that is, over 20 minutes. Fix prints 5 to 10 minutes.

Kodak Fixing Bath F-6 (I like this one better)​

Odorless Bath for Films, Plates, and Papers

Water, about 50 Celsius (125° F.) --- 600 ml
Sodium Thiosulfate (Hypo) --------- 240 g
Sodium Sulfite, desiccated ----------- 15 g
* Acetic Acid, 28% -------------------- 48 ml (see below)
Kodalk -------------------------------- 15 g
Potassium Alum ---------------------- 15 g
Cold water to make ------------------ 1 liter

* To make approximately 28% acetic acid from glacial acetic acid, dilute three parts of glacial acetic acid with eight parts of water.
Dissolve chemicals in order given. To prevent sulfurization, mix the potassium alum separately in a small amount of hot water then add this last with rapid stirring.
This bath should be used in conjunction with a stop bath such as Kodak Stop Bath SB-1 or Kodak Stop Bath SB-1a, or an acid hardening bath such as Kodak Hardening Bath SB-3 to obtain the full useful hardening life. The hardening life (capacity) is equal to that of Kodak Fixing Bath F-5 provided an acid stop bath is used. With a water rinse the life is about one-half that of Kodak Fixing Bath F-5.

Note that you can use less-concentrated acetic acid if you end up with the total amount in solution. The math depends on the concentration you can get, but say you have access to 5% distilled white vinegar. Using the following equation you can work out the amount of vinegar to use in place of the 28% acetic acid:

Q1/Q2 :: C2/C1 or… Q1 x C1 = Q2 x C2
Where
Q1 = quantity 1, Q2 = Quantity 2, C1 = Concentration 1 (%), C2 = Concentration 2 (%)

First, you have to find the acetic-acid concentration in the final solution, so:

Q1 = 48ml (the amount of 28% acetic acid called for in the formula)
Q2 = 1000ml (the total amount of the fixer)

C1 = 28% (concentration called for in the formula)
C2 = ? (the concentration of acetic acid in the final one-liter fixer)

Q1 x C1 = 48 x 28 = 1,344
Q2 x C2 = 1000 x ?
Solving for the unknown: 1000 x ? = 1,344
dividing both sides of the equation by 1000 gives us: 1344/1000 = 1.34% (acetic-acid concentration in final solution)

Now that we know that, we can find how much 5% distilled white vinegar to use to achieve the same:

Q1 = ? (the amount of 5% distilled white vinegar we need to use)
Q2 = 1000ml (the total amount of the fixer)

C1 = 5% (concentration of our vinegar)
C2 = 1.34 (the concentration of acetic acid in the final one-liter fixer)

Here we go:

Q1 x C1 = ? x 5 = 5x?
Q2 x C2 = 1000 x 1.34 = 1,344
Solving for the unknown: 5 x ? = 1,344
dividing both sides of the equation by 5 gives us: 1344/5 = 268.8ml (the amount of vinegar to use)

Note that you'll have to make sure that the final volume does not exceed one liter, but, in this case, it's not a problem.

This is how I mixed F-6 for years. F-6 has less odor but hardens just the same as F-5

Hope this helps,

Doremus

 

[DoctorMikeReddy]

Thanks all! Lots to go on
In the short term, I’m going to try the Kodak Rapid Fix with Hardener Liquid (comes in two bottles) to see if it does what it needs to with the Liquid Light emulsion. However, even getting this was hard; much searching of Internet links, which mostly said “Out of Stock” and such. When I have more time I’ll investigate making my own, but I have a pop up Photo Booth Thing at the end of the month and wanted to go with what I know.