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Bill, 70's military B&W
17-Nov-2012, 07:44
I know that many use the cans for blowing dust off negatives and other house cleaning purposes, but does anyone use the cans of pressurized gas to displace regular air?
When you open up a chemical, it has a shelf life of only a few months, does displacing the air (oxygen) with a spray of ethylene chloride (if I remember right) prolong the shelf life of the chemical?
Is there any combination that I should avoid? I know to keep the can upright.

lenser
17-Nov-2012, 08:05
I remember buying cans of Nitrogen (I think, or some other inert gas) for just that purpose at the local camera store. Don't know if it's still around or not.

Jeff Bannow
17-Nov-2012, 08:25
There are products for topping off bottles of wine. That should work, although I don't know how expensive it is.

Jim C.
17-Nov-2012, 08:45
What you're looking for is blanketing gas, I use them to protect moisture sensitive materials I use.
There's specific kinds of blanketing gas, one is flurocarbon based the other is inert gases.
Problem with the flurocarbon types is that they tend to contract so the container will suck in slightly, not good if you intend
to store stuff for along time as the containers may rupture, not dangerous but can be messy.

Bloxygen is an inert gas blend - http://www.bloxygen.com/purch.html

flurocarbon based
Xtend-it - http://www.smooth-on.com/Urethane-Rubber-Ac/c1118_1203/index.html
Burp -http://www.anchorseal.com/miscProducts.html

The last option would be to get a small inert gas tank and have it filled at a welding gas supplier with dry nitrogen.

E. von Hoegh
17-Nov-2012, 08:51
Or argon, as used in TIG welding.

wallrat
17-Nov-2012, 09:58
Bill, I use the Air-Evac Bottles. Freestyle sells their own version under the Arista name and there is another brand name that sells larger bottles (up to 2 gallons). They are great for keeping chemicals fresh as once you are done with the chemical, you smash the bottle down and cap it when the chemical is even with the top of the bottle and then you eliminate the issue with air in the bottle and it's far more reusable, less expensive, and more ecologically friendly than using air replacement techniques. My chemicals last forever (not literally). I have a bottle of rapid fixer in a black 2 quart air-evac bottle that is going on 9 month old and it still fixes great and passes the fix test. I don't use the Illford all the time, but the fact that it's lived that long is a testament to these bottles effectiveness.

Bill, 70's military B&W
17-Nov-2012, 21:13
Thanks, wallrat and everyone, I just placed an order with Freestyle for the evacuation bottles. For the smaller bottles I use the ethylene chloride that is commonly found at Computer stores for blowing away dust. I just spray a small amount into the neck of the bottle and put the lid on. I'm not getting all the Oxygen out but I am reducing it. I just hope there is not a chemical reaction that I am not aware of. The evacuation bottles were not expensive and will do a much better job, I'm sure.

Ian Gordon Bilson
17-Nov-2012, 21:24
Bill,the compressible bottles have a poor reputation,as a Web search will reveal. The flexible plastic is the wrong type for chemical storage and is oxygen-permeable.
Which kind of defeats the intended purpose..
Ordinary Butane gas will do the job - the refill cans for barbeque lighters.I keep a small gas torch handy - a decent puff into the bottle will blanket the chemistry nicely.
No ignition sources,for obvious reasons.

wallrat
17-Nov-2012, 22:09
I was told by freestyle that the makeup was changed some time ago to fix that issue. I have seen zero issues with over 2 years of using them.

Bill, 70's military B&W
18-Nov-2012, 07:52
Well, I have some collapsible bottles coming from Freestyle, and I will also be using the 1 gal plastic bottle that the distilled water comes in. As far as cleaning the collapsible bottles, I think I'll keep them dedicated to a specific chemical and cleaning should not be all that problematic. I hope wallrat is right and the bottles have been modified.

So far (a few weeks in my case) I'm using the compressed ethylene chloride from Best Buy at about $3.50 for a large can to displace the oxygen. It's cheap, no odor, should work! My only concern would be if there is some chemical process, some incompatibility I am unaware of, either with the chemicals or the plastic container. If there is a problem then as Ian said Butane is another alternative.

I was reading and someone said that stop bath and fixer are not sensitive to oxygen, so that gas displacement or evacuation bottles are not needed. Is that true?
Besides the developer what other chemicals do I need to be guarding against oxygen?

Thanks, Bill

wallrat
18-Nov-2012, 10:41
I'm unsure about stop but I know that fixer tolerates oxygen far more than developer which is the most sensitive. I only use Rodinal and PMK Pyro, both of which are 1 shot after mixed and their stock solutions would outlast Cockroaches during the nuclear D-Day. Again, I've had great luck with the evac bottles but I respect everyone's preferences and opinions. The good news, regardless, is that they are cheap to try so you can make your own opinion. It's like asking people what the best film, paper, developer, etc is. You'll find a large number of varying opinions which is good, variety is the spice of life! I'm glad you are getting started Bill and using this wonder resource for what it is!


-Bill

Bill, 70's military B&W
18-Nov-2012, 21:09
Everyone, I really appreciate everyone's input and help. I have never been on a chat room, so this is the closest I've come. This Forum has been great, I've been out with a couple of the members, watching how they do it, pestering them to no end with questions... I feel a lot more confident now. Now if someone could just show me how to make my so-so prints, look good!

Thanks to everyone,
Bill

EdSawyer
18-Nov-2012, 21:15
nitrogen is way cheaper than argon, but argon would work too.

chuck94022
21-Nov-2012, 00:47
I was reading and someone said that stop bath and fixer are not sensitive to oxygen, so that gas displacement or evacuation bottles are not needed. Is that true?
Besides the developer what other chemicals do I need to be guarding against oxygen?

Thanks, Bill

I would not invest a lot in protecting stop bath. It is acetic acid, basically lemon juice or vineger (don't drink it). And anyway, you can substitute water instead of the acetic acid, works just fine. You just need to stop the development process, and using water instead of stop bath seems to be gentler on the film.

Fixer I'd go ahead and protect.

"70's military B&W"? Didn't you run out of shooting opportunities about 40 years ago? ;-)

AJ Edmondson
21-Nov-2012, 08:11
The old process of using glass marbles to displace the liquid to the point of overflow still works well... cheap and environmentally friendly as well. ;- )

Drew Wiley
21-Nov-2012, 17:00
Yeah ... those accordian bottles are kinda cheapo, and the thin walls will pass oxygen.
Might be OK for temporary use. But I never liked them. I use amber glass bottles for anything serious, and pour the chem into smaller bottles if there's too much air. You can
rent a cylinder of argon from welding suppliers, or if you're in the right part of the country, go to your local winemaking supplier (or internet order).

Bill, 70's military B&W
22-Nov-2012, 07:24
I know a couple of Pharmacists, so I'll be asking them about amber bottles. I'm not sure they still get chemicals in bottles like that anymore. I'll find out, if not then where would a good source be? Anything local? I mean from a source that would commonly be in any community. If not then a mail order source.

What about mixing chemicals in the plastic bottle that the distilled water comes in. I know it's not opaque, but if I store it in a cabinet in the DR, that would be a dark cool place. I would not have to clean it, EVER. I can easily squeeze at least a quart of air out of it. Smaller quantities could be put in plastic soda bottles. This disposable plastic system would be the cheapest and easiest system I can think of. What are the negatives of doing it that way?

John Bowen
22-Nov-2012, 07:52
I purchased my amber bottles from Photographers Formulary. They have/had a nice selection of sizes everything from about 2oz to a gallon.

Bill, 70's military B&W
23-Nov-2012, 10:01
John, Photographers Formulary looks like a good source. Prices do not look too bad either. Thanks, Bill

vinny
23-Nov-2012, 10:20
I use wine preserver in the brown cans search amazon.com. The accordian bottles i've thrown out.
I don't worry about air in my pmk or rodianl but do top off my c41 and e6 stuff.

AJ Edmondson
23-Nov-2012, 15:44
Most of the amber bottles I use were 1 gallon containers of isopropanol from a local hospital. It has been a while since I needed any so I don't know how such "acquisitions" are viewed in todays' world.

Bill, 70's military B&W
23-Nov-2012, 18:28
AJ, thanks, I know a hospital pharmacist, that may work out.

No one is addressing my question about doing it the easiest way. What is wrong with using the plastic bottle that the distilled water comes in, you can squeeze it down at least a quart to empty air out, then any smaller portions go into soda bottles. You never have to clean them, just use new ones, they will not age, they get turned over just as fast as the chemicals do.
I know a lot of people do it just that way, what is the down side? All those plastic bottles are going to be bought and discarded anyway.
Bill

Michael Clark
23-Nov-2012, 22:28
Soda bottles leach less oxygen, they use a PETE 1 type plastic, its stamped on the bottom of the bottle. Milk bottles are not as oxygen proof and are not intended for long storage times.

Mike

RichardSperry
24-Nov-2012, 01:20
Bill,

I was once a proponent of recycling distilled water jugs. No more.
I have discovered that they occasionally leak. One was fixer. And one was distilled water unused.

They got holes in the crinkles; which if you squeeze them down to push out the air would cause even more stress, I would say. The fixer one had me assuming some chemical reason. When the distilled water leaked, I realized it was just the container itself.

I just bought a bunch of the gallon data containers from B&H for $5. They have amber glass for like $15.

Bill, 70's military B&W
24-Nov-2012, 07:19
Thanks everyone for the advice and passing on your personal experiences, it saves me from making the same mistakes. I'll be pestering my Pharmacy buddies for some amber bottles and if that fails then I'll be buying on line. This is what a Forum is best for!
Bill

AJ Edmondson
24-Nov-2012, 07:29
You actually had it right with the glass soda bottles (the small ones)! Sure you end up with a lot of bottles but (1) because of small size they stabilize (temperature) faster, (2) if filled to overflow there is not enough air to worry about and (3) they are free!

vinny
24-Nov-2012, 08:12
Milk jugs/ gallon distilled jugs have leaked on me several times as well.

wallrat
24-Nov-2012, 10:15
Btw, I don't use the name brand accordion bottles as they are thin and fall over. I use the Arista Air Evac bottles which are thicker than any chemical bottle I've ever used that is plastic. I realize everyone has favorites, but I like them just fine. I have a disolved oxygen meter from years of planted aquariums and I tested them repeatedly when I started using them and they are as good or better than the glass bottles I also use. I agree that I do not like the brown, name brand "Kalt" bottles. They are super thin and I noticed deterioration of chemicals similar to thin water bottles.