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  1. #51
    gainer's Avatar
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    Quote Originally Posted by Kirk Keyes View Post
    That's the requirement to meet the specifications for ACS Reagent Grade, just as I plainly stated above.
    You didn't answer my question. Never mind, I think I did. As you see, the batch that Mick Fagan got does not meet your spec for insoluble material, even though it is claimed to be Analytical Reagent grade. If that's good enough, then 20 Mule Team Borax is good enough. We usually accept the technical grade for photographic chemicals. Put your Adobe reader to work and search among the PDF files at www.borax.com for borax decahydrate Product Profile.

    You may not have known that borax decahydrate is about 10 times more soluble in either glycerol or ethylene glycol than in water.
    Gadget Gainer

  2. #52
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    Patrick;

    0.001 grams in 20 is 0.005 grams in 100 grams.

    0.005% is the specification. I think it does meet the spec. Please check your math!

    That level of solids would be invisible and would pose no problem photographically in most cases except for ultra small format films perhaps.

    PE

  3. #53
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    Quote Originally Posted by Photo Engineer View Post
    Patrick;

    0.001 grams in 20 is 0.005 grams in 100 grams.

    0.005% is the specification. I think it does meet the spec. Please check your math!

    That level of solids would be invisible and would pose no problem photographically in most cases except for ultra small format films perhaps.

    PE
    No comment on the fact that 20 Mule Team Borax is rated Technical grade? Both the manufacturer and the MSDS claim it to be more than 99% borax decahydrate. That puts it with the analytical reagent grade for borax content. Most of the uses to which it is put are at least as stringent as photographic use for the allowable contents of the remaining fraction of 1%. Tell me again why I should not use 20 Mule Team Borax in D-76 or the like. I know that there is no chlorine or phosphate. I do not know the amount that is insoluble, but I do know I have never seen any in my solutions.

    I have a question about the test for insoluble contents. You know very well it is beyond the capability of most APUGers. The water used must have no mineral content whatever, and also no organic content, which might include bacteria or such that can be found in some of what we buy as distilled water. The lab equipment that is described is not usually found in our darkrooms. Ordinary, or even extraordinary, filter paper is apparently not sufficient. However, if you have the necessary equipment, you could do that test on a cheap sample of 20 Mule Team Borax. Are you afraid you will not find the expected insoluble material, or maybe that you will encounter some mule excrement?
    Gadget Gainer

  4. #54

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    Mule excrement!? I always knew that would make a good film dev!

  5. #55
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    Patrick;

    That extra 1% could be very finely ground sand, crushed up in the processing of the raw Borax. IDK and I really don't care! If it is though, I assure you that I don't want it in my film developer. You can go for years with no problems and then have a gotcha. I prefer to avoid that.

    You are an aeronautical engineer. I am a chemist and photographic engineer. I've seen a number of amateurs build powered aircraft, and I recently watched one of them on tv have a crash. He survived, but the point is that he had many flights that went well but he was an amateur.

    I am not any better than he was. I can build paper airplaines for my grandkids, but OTOH my ability in the darkroom or a chemical laboratory is as a professional. So, I'm trying to present good professional advice here for people to get good professional and repeatable results with their processing. Your advice will work, but is on the knife edge of potential failure just like the airplane I mention above. You can fly for years, and then one batch will mess up.

    The worst part is that you might not see it until you make a print, or, with bad eyesight someone else might have to point it out to you.

    So, what you say will work, but maybe not all of the time. Surely I have shown elsewhere how using volumetric measurements vs weight for some solids can cause an error of up to 20%. I am trying to develop good laboratory habits and good knowledge amongst those who follow. When all of the analog Photo Engineers are gone, I truly don't want people in the lab doing real professional quality work to try to follow the methodologies you espouse. I'm sorry to have to say this, but it is the truth.

    Remember next time that you want to argue this that you dropped out of chemistry!

    I'll have fun anytime helping with using household products for developers as a lark. To me it is like building paper airplanes would be to you. But, I would never ever try to do that for serious work. And, another factor is this. If everyone used store bought borax, then what would happen to legitimate suppliers of genuine Photo Grade chemicals.

    I apologize for the rather strong tone of this post Patrick. Your work and reputation stand, but not for truly serious work IMO and I hope that the people reading this understand my POV.

    PE

  6. #56
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    So your point of view is that I have not learned anything out of college about chemistry. Does that come from personal experience? I cannot imagine that you worked for years in a Kodak research lab and did not learn anything you did not know when you started. I learned more about aeronautical engineering after I started at NACA than I did at WVU and I went on to make original contributions. What I learned in College was how to learn.

    That said, why do you think that a product intended for so many uses, including eyedrops, face and hand creams...tell the truth: you have not bothered to look up all the recommended and actual uses of 20 Mule Team borax, have you? Almost any one of these personal care uses would detect the sort of things that would keep it from being useful in photography.

    I contend you do not know the true, or at least the traditional meaning of the word "engineer". I have tested the requirements for accuracy of all the developers and other solutions where I have used volumetric measurements of solids, and have proposed methods for making them consistent. I have used them in cases of "put up or get out" and have many autographed photos of great artists of the music and dance world to show that I put up, in action, not posed situations.
    Gadget Gainer

  7. #57
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    BTW, you really should study the process by which the purified borax is extracted from the raw before you go commenting on what you think it is. That is, if you really are an engineer.
    Gadget Gainer

  8. #58
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    Quote Originally Posted by gainer View Post
    So your point of view is that I have not learned anything out of college about chemistry. Does that come from personal experience? I cannot imagine that you worked for years in a Kodak research lab and did not learn anything you did not know when you started. I learned more about aeronautical engineering after I started at NACA than I did at WVU and I went on to make original contributions. What I learned in College was how to learn.

    That said, why do you think that a product intended for so many uses, including eyedrops, face and hand creams...tell the truth: you have not bothered to look up all the recommended and actual uses of 20 Mule Team borax, have you? Almost any one of these personal care uses would detect the sort of things that would keep it from being useful in photography.

    I contend you do not know the true, or at least the traditional meaning of the word "engineer". I have tested the requirements for accuracy of all the developers and other solutions where I have used volumetric measurements of solids, and have proposed methods for making them consistent. I have used them in cases of "put up or get out" and have many autographed photos of great artists of the music and dance world to show that I put up, in action, not posed situations.
    Patrick;

    You have missed the point entirely.

    I learned chemistry in college and learned how to learn, then I spent 32 years or more doing quantitative lab work on photography becoming a photographic engineer.

    You learned engineering in college and learned how to learn, then spent X years doing aeronautical engineering. But, you did not spend that time doing photographic engineering or chemistry as a profession!

    My background does not qualify me to design airplanes even though I know the theory of their operation. So, any advice I give in this regard would be less authoritative than yours.

    My comments here are given in the sense that I'm trying to "teach" things to be done in the right way and point out the potential pitfalls and I think so is Kirk. You appear to be dismissing our advice, which is based on our years of experience, as being unnessesary and essentially trivializing it.

    The comment that I don't know about the uses of borax is rather gratuitous.

    We kept eye cups with borax solution in all labs in case of splashes of some bad chemicals to the eyes. That was discontinued and the cups were replaced with eye wash stations.

    I also know that borax is toxic to citrus fruit trees, and that it is used as a poison for cockroaches. You forgot those two. Most importantly, it is very toxic to children and ingestion of even a small amount can be fatal. Therefore the roach tablets have to be carefully placed in a 'roach motel' type container.

    So, those using borax salts for any reason should make sure that they are well out of the reach of children.

    PE

  9. #59

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    Quote Originally Posted by gainer View Post
    The tea wore off suddenly about the time the exam began and I don't remember anything until the assistant woke me when time was up.
    Pat - why do you keep reminding us about failing your chemistry exam? It's not a good way to support your side of the arguement!

  10. #60

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    Quote Originally Posted by gainer View Post
    I have a question about the test for insoluble contents. You know very well it is beyond the capability of most APUGers. The water used must have no mineral content whatever, and also no organic content, which might include bacteria or such that can be found in some of what we buy as distilled water. The lab equipment that is described is not usually found in our darkrooms. Ordinary, or even extraordinary, filter paper is apparently not sufficient. However, if you have the necessary equipment, you could do that test on a cheap sample of 20 Mule Team Borax. Are you afraid you will not find the expected insoluble material, or maybe that you will encounter some mule excrement?
    You're right - I don't expect most APUGgers to to be able to do this test. I know there are a few that are qualified to do something like this. But it obviously requires a 4 place balance, at the least a very good 3 place balance. Steam bath - a hot plate would suffice, just keep it near boiling without actually losing much volume. I think this gives the silicates a chance to drop out of solution at the high pH in the solution.

    And despite all the fancy platinum filters it talks about, I've never even seen one like that. I suspect that porcelain Gooch-type filtering crucibles with the proper glass-fiber filter paper is really what people use. I have had access to those types of things at work in the past. And for your water, store bought Deionized water would be fine - prefilter it with the same glass-fiber filter that you do the test with if you are concerend about bacterial matter or other solids in it.

    But it is a very simple test to do. If I had a 4 place balance, I would oblige you with a test.

    (By the way, I almost bought on at a swap meet years ago. Recovered by the police, sold to a photo-stuff dealer. But it was not functional and I didn't want to risk the chance that it was not going to be repairable at a reasonable cost.)

    Mule excrement - that's funny!



 

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