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Thread: Mallory 4 cap can is one roll with 4 diff lengths off foil.how to

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    Mallory 4 cap can is one roll with 4 diff lengths off foil.how to

    The Mallory can had four different capacitor specs.I took out the can,& took out one roll with four different lengths of foil to make up the different mfd and volts.these capacitors were leaking and needed to be changed.
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    Last edited by Stevi q; 08-20-2017 at 10:44 AM.

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    Quote Originally Posted by Stevi q View Post
    The Mallory can had four different capacitor specs.I took out the can,& took out one roll with four different lengths of foil to make up the different mfd and volts.i dunno .it worked apparently.There are two resistors that join 3 of the caps together .I am wondering ,do I need these resistors still. Or were they in there because of the Mallory style of cap with a continuos roll.Pleas help.Thanks
    I do not think we have enough information. Please include a pic of what you are trying to get across please.

    Thanks,
    nosaj
    J M Fahey likes this.

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    A lot depends on whether you can absolutely guarantee that all caps with that pinout would have conductively-joined rolls of aluminum foil. It is also possible that the roll was the roll of permeable spacer stuff that carries the electrolyte and spaces the foils apart, the foils being separate sheets. You could tell this with an ohmmeter to see if the four terminals appear shorted together on a new, pristine cap.

    It's hard for me to believe that this was what Mallory intended to do. There are valid reasons for having impedances between the caps in a can, and Mallory knows/knew it. Maybe this is what happened when Mallory first hired MBAs. Lowered the IQ at Mallory and raised it for MBAs in general, I suppose. Or that it's a counterfeit "Mallory" cap. That might be worth some money to someone with a good faking factory.
    Amazing!! Who would ever have guessed that someone who villified the evil rich people would begin happily accepting their millions in speaking fees!

    Oh, wait! That sounds familiar, somehow.

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    Old Timer olddawg's Avatar
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    Quote Originally Posted by nosaj View Post
    I do not think we have enough information. Please include a pic of what you are trying to get across please.

    Thanks,
    nosaj
    Are you saying the resistors were located "internally" inside the can cap? If they were, I would remove them and replace the segments with modern discrete caps. If they are external on the lead dress I would certainly use them. I've stuffed a few of these cans and have never paid a lot of attention to the crap inside other than to get it all out and connect the new caps to the correct leads.

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    OK, thought about this for a bit. I may have misunderstood the OP. If there were four >> different << lengths of aluminum foil in there, not all connected, it may be just fine. The negative side of all the capacitor sections would be connected, as they are all the "negative case" side of the four cap sections. If there were four sections NOT conductively connected to one another, but one section of each foil to each external tab, that's OK too. The foil sections for each external lead are (theoretically) insulated from the common negative side of the cap by the aluminum oxide on the aluminum foils. That's how it's supposed to work.

    I guess, more to the point, as the first replyer said, what exactly are you describing?
    Amazing!! Who would ever have guessed that someone who villified the evil rich people would begin happily accepting their millions in speaking fees!

    Oh, wait! That sounds familiar, somehow.

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    Old Timer J M Fahey's Avatar
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    Confusing post to say the least.
    But IF you are telling us you disassembled a 4 section cap can and found 4 foil rolls there, and they are different length, well, tatīs about what Iīd expect to find there.
    Of course you damaged it beyond repair.

    No reason for resistors to be *inside* the can though.

    You are not even telling us what is *printed* in the case, for Godīs sake, is this Puzzle Week or something?

    Post gut and can pictures.

    I know some cap assemblies are fit inside old/vintage/original cans, I guess even empty cardboard sleeves are sold, for amps to *look* vintage.
    And also thereīs plain fakes.
    Juan Manuel Fahey

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    Quote Originally Posted by Stevi q View Post
    The Mallory can had four different capacitor specs.I took out the can,& took out one roll with four different lengths of foil to make up the different mfd and volts.these capacitors were leaking and needed to be changed.
    Ok according to your picture the cap can is trash now. But you got to see how one is constructed. You will need to restuff it with modern electrolytics or replaced it with a new CDE or JJ cap can. Unfortunately you cannot put that one back together and expect it to work. But even destruction can turn into a good learning experience.

    nosaj

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    Senior Member Malcolm Irving's Avatar
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    I’m not saying I know that this is actually how they do it, but one possibility is to make up 8 layers (with different lengths as appropriate) as follows:
    Cap1 +ve foil,
    Ground foil,
    Cap2 +ve foil,
    Ground foil,
    Cap3 +ve foil,
    Ground foil,
    Cap4 +ve foil,
    Ground foil.
    Then roll the whole lot up in one big roll. The ground foils would screen each cap from the other caps.

  9. #9
    Old Timer J M Fahey's Avatar
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    What was printed on the cap can?
    Juan Manuel Fahey

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