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davidwrogers
30-Jul-2011, 12:31
Does PVC cement react in any unpleasant ways with the various chemicals used to process B&W film? Or can I hack my way through some plastic and glue it back together with abandon, concerned only with how light-tight the monstrosity will be rather than how deformed my emulsions will become? I need to build a tank to hold and develop 1 piece of 4x5.

John Koehrer
30-Jul-2011, 13:30
PVC cement seems to work and not bother anything. If you're building something to process film though the white stuff isn't always safe(rumor) it's not completely opaque.

Ari
30-Jul-2011, 13:37
Make sure you get cement that lists PVC first as its applications.
I just built two tanks for 8x10 film, and there was no ill-effect from the cement/chemical mix.
It dries and sets very quickly, but make sure you give it time to air out a little, as the cement vapours are quite noxious

davidwrogers
30-Jul-2011, 15:52
ARI:

Went fishing with the right bait, here. To wit: what did you build the tanks out of? I plan on getting a hanger in the mail and building a PVC fortress around it. Do they sell PVC in anything other than tubular form?

Ari
30-Jul-2011, 17:11
Damn, I fell for it!
David, I used PVC, and to answer your question, finding PVC sheets depends on where you live.
I had no luck at Home Depot et al., but I found a plastics manufacturer in town who also supplied PVC, and even cut it to my specs at no extra charge.
You might have to order online if you're in a remote area, but make sure that the cutting is done with the proper tool, i.e. no hand saws or the like; the edges must be close to perfect in order to bond well.
As stated previously, get the right cement, and I added Plumber's Goop on all the joints to make sure it was watertight.
You'll find that once you make the first tank, you'll want to make everything out of PVC, because it bonds so well and so quickly (hello, darkroom sink...).
Good luck!

ps: Might I ask why you want a tank for only one piece of film? You could get by easily with a 5x7 tray in the dark, or taco method in a 120 tank.

D. Bryant
30-Jul-2011, 18:16
Does PVC cement react in any unpleasant ways with the various chemicals used to process B&W film? Or can I hack my way through some plastic and glue it back together with abandon, concerned only with how light-tight the monstrosity will be rather than how deformed my emulsions will become? I need to build a tank to hold and develop 1 piece of 4x5.

Yep! It's been used safely for decades in the photofinishing industry. Sheets of PVC maybe purchased and welded together.

Ed Brock
30-Jul-2011, 21:05
You can also use ABS sheets. I've seen motion film processors built of the opaque gray sheets and it also come in black. Just set the sheet edges together and the thin ABS solvent/glue wicks right into the joints providing a waterproof seal and a rugged weld.

davidwrogers
31-Jul-2011, 07:06
Thanks for the answers. Very informative. As for why I need to develop one piece at a time: economists would call it a scarcity of resources.

Ari
31-Jul-2011, 07:36
In that case, you might be better off, and a few dollars richer, by processing in a tray.
I'm not sure of how much volume you intend to process later on, but developing one sheet at a time will become very tedious.
Make a tank to hold four film hangers, perhaps, or learn how to process multiple sheets in a tray.
Good luck.

Steve Smith
31-Jul-2011, 08:58
In that case, you might be better off, and a few dollars richer, by processing in a tray.

Or a Paterson Orbital... which is really just a fancy tray.


Steve.

Ari
31-Jul-2011, 09:11
Or a Paterson Orbital... which is really just a fancy tray.


Steve.

Is that what it is?
I always looked at it curiously, because it resembles a toilet plunger.

Nathan Potter
31-Jul-2011, 10:20
Actually standard PVC cement will be gradually altered by darkroom chemistry. Old tanks that I have used a great deal show quite distinctive whitish cast to the areas of PVC cement originally used to seal joints. I'm not sure, but have a hunch that stop bath (acetic acid) may be partly responsible. But otherwise the tanks work fine. They were made from 1/4 inch sheet stock that was grey - and opaque.

I buy 3/8 thick, grey PVC in 4 X 8 ft. sheets from a local plastics supplier for about $130 per sheet.

Nate Potter, Austin TX.

Ari
31-Jul-2011, 10:44
I'm not worried about stop, since I never use it on film; but if it does indeed cause deterioration of the PVC, it's good to let others know that using water instead of acetic acid is good for several reasons.

Rick A
1-Aug-2011, 11:57
You can always use the "taco method" in an Arista or A-P plastic two reel tank, pPaterson tanks don't work. It still uses way more chems than tray processing, but if you already have the tank for 35mm or 120 film you don't have to shell out any money. I used to process 4x5 one sheet at a time in plastic take out cartons from the local Chinese joint.

Drew Wiley
1-Aug-2011, 12:03
If used correctly, neither PVC or ABS cements are sealants. They are solvents which
melt the two plastic surfaces together. Often a primer is also needed to etch the mating surfaces.