Film developing tank material ?

[Neil t3]

Hello all .
I finally managed to track down something that doesn't exist .
No , not a unicorns horn or a flying pig , but a HP Combi-Plan 7x5 !

I've been using the 5x4 HP Combi-Plan daylight developing tanks since I first started with 5x4 , and having tried other systems I prefer them .
I knew they did one for 7x5 but have only seen one for sale once , and someone beat me to buy it ....
A few of these came up late last year in the Netherlands , a bit pricey , but I snapped one up straight away .
It was listed as a daylight developing tank , but clearly isn't as it has to filling point or draining point . But it was the film holder I was interested in .

The way I'm going to use it is as a dip and dunk system where I'll use a film changing bag to hold three similar containers containing the developer , stop bath and fix .

With regards to the tanks , I just need to decide what to make them out off .

I know a local firm in Glossop that can make some out of stainless steel , though I don't know what grade of steel to ask for that will be O.K with the chemicals used .
I'm guessing these wouldn't be very cheap , but will cost what they cost if these are what's needed .

Or I can DIY some myself and use Perspex glued together with silicone sealant the same way as you make a fish tank .
But how would Perspex and silicane behave with B&W photographic chemicals ?
As I have Perspex already , it's only a tube of silicone I need , likely costing only a few quid , unless I need the same type used for fish tanks .

But would it stand up to the chemistry without damaging my negatives ?
Both the silicone and sealant/adhesive ?

Your opinions and experience would be appreciated .

 

[Ian Grant]

I have a Yankee 5x4 development tank, I also have a 2nd film holder I bought a couple of weeks ago. I really use it mostly for 9x12 & Quarter plate.



I wondered about having the guides 3D printed.

Stearman Press copied this idea.





This is a stainless steel Dallan tank, I have a second with a filler, and drain, system.

Ian

 

[Petrochemist]

View attachment 5917

View attachment 5918

This is a stainless steel Dallan tank, I have a second with a filler, and drain, system.

Ian

I've just got a second Dallan tank, only to find it leaks badly at the bottom.
I'm going to try hot melt glue on it first (less messy than araldite especially as it can be remelted & repositioned)
Both mine have fillers & drains, though the first didn't have the cap for the drain (a bung does the job every bit as well)

FWIW I'd expect (perhaps foolishly) acid/base reactions to be the major issue with darkroom chemicals, so silicone & organic materials should stand a better chance than solder - not that solder would be appropriate for Neil's issues!

 

[Neil t3]

I've just got a second Dallan tank, only to find it leaks badly at the bottom.
I'm going to try hot melt glue on it first (less messy than araldite especially as it can be remelted & repositioned)
Both mine have fillers & drains, though the first didn't have the cap for the drain (a bung does the job every bit as well)

FWIW I'd expect (perhaps foolishly) acid/base reactions to be the major issue with darkroom chemicals, so silicone & organic materials should stand a better chance than solder - not that solder would be appropriate for Neil's issues!

So you reckon the chemicals I'll be using won't harm either the perspex or silicone sealant then ?
Looks like a DIY option might be the answer then .
I'll still be getting a quote for a set of three stainless steel tanks though , if it's reasonable I'll have them make them .
Stainless would me nice and it'll save me time messing around doing my own .

 

[Petrochemist]

So you reckon the chemicals I'll be using won't harm either the perspex or silicone sealant then ?
Looks like a DIY option might be the answer then .
I'll still be getting a quote for a set of three stainless steel tanks though , if it's reasonable I'll have them make them .
Stainless would me nice and it'll save me time messing around doing my own .

I don;t have anything like Ian's experience with photographic chemistry, but plastics are generally OK with the reagents used

 

[Nas]

Have you thought about plastic food storage containers? I bought a large Wista 45DX kit which included metal hangers and 3 food storage containers the previous owner had used for developing the sheets. They were very clean and looked unaffected from any chemistry.

 

[Neil t3]

Have you thought about plastic food storage containers? I bought a large Wista 45DX kit which included metal hangers and 3 food storage containers the previous owner had used for developing the sheets. They were very clean and looked unaffected from any chemistry.

For the 5x4 combi-plan holders I have , I also have some square food storage boxes , they are too wide and use twice as much chemistry .
But is I'm usually daylight developing I use them in the washing stage where I use them as a series of water changes whilst I'm developing the next batch of film .

Looking at the 7x5 film holder it might just fit nicely in those tall cereal storage type ones , cut down in height .

I'll have a look in a few shops when I get chance later in the week , hopefully I'll get lucky .

 

[Nas]

For the 5x4 combi-plan holders I have , I also have some square food storage boxes , they are too wide and use twice as much chemistry .
But is I'm usually daylight developing I use them in the washing stage where I use them as a series of water changes whilst I'm developing the next batch of film .

Looking at the 7x5 film holder it might just fit nicely in those tall cereal storage type ones , cut down in height .

I'll have a look in a few shops when I get chance later in the week , hopefully I'll get lucky .

It's the tall cereal tubs that came with my 5x4 kit. They're just the right size for the Kodak hangers the previous owner was using.

 

[AERO]

When it comes to good source for plastic boxes UK company VIKING office supplies have a huge range .
I just bought one for a print washer project..395 x 255 x 290 mm ( 15.55×10.04×11.42 inches)
19 litres This box is normally for use with A4 FILES ....and cost, delivered next day - £11.34

 

[Neil t3]

When it comes to good source for plastic boxes UK company VIKING office supplies have a huge range .
I just bought one for a print washer project..395 x 255 x 290 mm ( 15.55×10.04×11.42 inches)
19 litres This box is normally for use with A4 FILES ....and cost, delivered next day - £11.34

I'll check them out , thanks .

I've just had four cereal ones delivered today that seems the right measurement's, but with the taper the film holders don't fit .

I'll check out Dunelm and IKEA first as I can take the film holder to try them out .
If not I'll try Viking.

 

[AERO]

I'll check out Dunelm and IKEA first as I can take the film holder to try them out .

If not I'll try Viking.