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  1. #31

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    Good thougts.

    I had used carbon rods from dry cell batteries when I last played with electrolosis (about 30 years ago).

    I can see why not to use poison metals, however, I would think stainless should be OK as any iron leached from it should be headed right back to the electrode from the current in the solution... Anyway, I guess I've got the silver wire around to use. I guess platinum wire would work well too, and I've always wanted to get a bit of that for various projects...
    Kirk

    For up from the ashes, up from the ashes, grow the roses of success!

  2. #32
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    Some photos

    I am now at the point of being able to replicate results to within about +/- 5 mv, but with a slope adjustment as the solution becomes more dilute. I am working on that. It may be due to having immersed too little of the billet in the electrolyte.

    Here are photos of the reference electrode, the billet, the bridge and a trial setup of a beaker ready for precipitation of a real emulsion. The reference electrode is immersed in its conditioning/storage solution, and the bridge is also immersed in its own gel/salt storage solution. The bridge is marked as to polarity and the salt that it is to be used with. These are two critical items in this measurement.

    The making beaker in the 4th picture contains 2 inlet lines for salt and Silver, a temperature probe, the plated Silver billet, and the bridge. The bridge is a mockup in this but not in the other picture. The bridge is connected to the salt solution beaker on the far right which contains the reference electrode.

    The pump is partially seen to the far left.

    Both electrodes are connected to the VOM. It is then connected to a PC with a cable and data logging can be carried out as a function of time.

    PE
    Attached Thumbnails Attached Thumbnails Reference Electrode.jpg   Silver Electrode.jpg   Bridge.jpg   Complete Making setup.jpg  

  3. #33

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    In the first photo - the one of the reference electrode - it looks like you have the ref electrode in it's storage tube, right?

    I like how you can see the coating/plating on the silver electrode, that's good to know as it should help determine how much plating has occured.

    The last photo is getting pretty crowded with tubes... Make sure you leave room for the stir bar! ;^)

    Also, you're not seeing any interference from using a magnetic stirrer, right?
    Kirk

    For up from the ashes, up from the ashes, grow the roses of success!

  4. #34
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    Yes, I keep my reference electrode in the storage solution at all times. I actually store the Silver electrode in distilled water, and the bridge is stored in electrolyte gel.

    I could not get the stir bar in. Actually, I may need a prop mixer.

    There has been no apparent effect from magnetic stirring at all. That does not mean that I will never see it, but so far nothing. If there were to be an effect, i guess I would go to shielded cables.

    PE

  5. #35
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    I have gotten several comments both positive and negative about this work. Some want to know why I am posting such complex technical material and I tried to explain that earlier. This methodology is the gateway to controlled, modern, high speed emulsion making.

    But, I have overlooked the other use which is also very important but has a much more immediate impact.

    Measuring the vAg of an emulsion during the wash step will help you tell whether the wash has been carried out to the optimum point. By measuring the vAg, you can tell how much halide is left in the emulsion and whether the wash is complete, incomplete or overdone. If overdone, it tells you how much extra salt should be added to bring the emulsion to the right salt level for best keeping and best speed. Also, at this point, you do not need a bridge.

    I need not comment on those who have responded in a positive manner except to say thanks.

    PE

  6. #36
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    I have been waiting for this aspect of emulsion making to be discussed for quite a while, and am thrilled that process control on a small scale is that much closer to reality. Repeatable, custom tailored emulsions are within reach.

    Once subbing polyester is nailed down, things could get really interesting.

    Bob M.

  7. #37

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    " Some want to know why I am posting such complex technical material ....."

    PE and All,
    Tell them to take up kniting. Nice and simple and won't get their hand dirty.
    Or better yet, just watch the TV.
    Realy, this is not a vocation or avocation for those who cannot see Beauty in the Complex.
    Bill

  8. #38
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    Bill;

    Rather a strong reaction, but these were polite inquiries and I answered as such. There is no problem but I felt that more information was needed. Thanks.

    PE

  9. #39

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    Yes PE,
    I do get carried away sometimes. No real insult intended.
    Bill

  10. #40

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    Making electrodes and measuring vAg off hand seems rather simple, although in practice it's taken a bit more work than expected! It's the making the rest of the emulsion and coating that seems to me to be the more complex task...
    Kirk

    For up from the ashes, up from the ashes, grow the roses of success!

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