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  • Multi-Section Capacitors - "Empties"

    From Peter Wieck@21:1/5 to All on Mon May 4 15:43:45 2020
    This has probably been asked-and-answered before, but:

    I am looking for multi-section "empties" - that would be the can and the phenolic wafer - so I can stuff them myself without the cutting-and-gutting otherwise necessary.

    Anyone aware of a source?

    Thanks in advance!

    Peter Wieck
    Melrose Park, PA

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  • From Big Bad Bob@21:1/5 to Peter Wieck on Wed Sep 30 10:23:22 2020
    On 2020-05-04 15:43, Peter Wieck wrote:
    This has probably been asked-and-answered before, but:

    I am looking for multi-section "empties" - that would be the can and the phenolic wafer - so I can stuff them myself without the cutting-and-gutting otherwise necessary.

    Anyone aware of a source?

    Thanks in advance!
    I have to wonder if you can buy these components from someplace that
    fabricates paper tubes and paper disks. When you manufacture things in
    large quantities you can often just have some "cardboard stamper" build whatever you want. The 'Assman' catalogue might even have something.
    Yeah, 'Assman'. No seriously.

    https://za.rs-online.com/web/b/assmann-wsw/
    (you can probably find something i whatdver country you are in, they are everywhere)


    something else that I think would be even MORE useful (to me) would be
    the kinds of gear you'd need to "roll your own tubes".

    Not only would be awesome for restoring and/or replicating old radios
    and TVs, it would also be useful for developing new kinds of vacuum
    tubes that could be used for things that nobody considered 60 years ago
    when tube research was (more or less) at its peak.

    I did some study on the glass/metal barrier. It looks like silver wire
    might be the simplest, but most tubes use a chemically treated copper [I
    forget what you do to it to make the copper oxide layer correct but it's somewhat simple] hut you need "the right kind of glass" that has a
    thermal expansion coefficient that's similar to the metal you pass
    through it AND wets nicely onto it to provide a correct seal.

    So yeah you'd need a source for that, too. And getter materials. And
    nitrogen purge zones for building the electrodes and stuffing the glass envelope. And a "hard vacuum" pumping system. Etc.


    --
    (aka 'Bombastic Bob' in case you wondered)

    'Feeling with my fingers, and thinking with my brain' - me

    'your story is so touching, but it sounds just like a lie'
    "Straighten up and fly right"

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  • From Peter Wieck@21:1/5 to All on Fri Oct 2 08:34:39 2020
    The problem with cardboard in close quarters with vacuum tube equipment is the heat. The multi-section cap in my Dynaco ST35 is less than two inches from the output tubes, which run at 240F +/-. For just one example. Not that there is any danger of fire -
    but it is quite warm. I also want the metal can look. I have found sources, even at reasonable costs - at quantities of 500 or more.

    Peter Wieck
    Melrose Park, PA

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  • From Big Bad Bob@21:1/5 to Peter Wieck on Fri Oct 2 11:44:41 2020
    On 2020-10-02 08:34, Peter Wieck wrote:
    The problem with cardboard in close quarters with vacuum tube equipment is the heat. The multi-section cap in my Dynaco ST35 is less than two inches from the output tubes, which run at 240F +/-. For just one example. Not that there is any danger of
    fire - but it is quite warm. I also want the metal can look. I have found sources, even at reasonable costs - at quantities of 500 or more.

    ah, I misunderstood. I have seen a LOT of multi-capacitor cardboard
    types but you're talking about a metal can. Yeah, maybe you can get
    some blind-end aluminium tubes, or aluminum tubes with end caps, to do
    the same job... ok not *exactly* the same but still. You'll still need
    some kind of insulator for the terminals. Maybe you can get some
    circuit boards made to do the job? Would need a lot of precise metal
    cutting for tabs, etc. on the aluminum. yeah, starting to sound like
    too much effort already...

    But inside the capacitor can I'd hide some "modern" electrolytics which
    are considerably smaller in size. I've heard of this being done in
    radio restorations where they dig the contents out of the can, swap in
    modern components, but give it "the look" of the original system.

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