Help me figure out this volume pot issue...

Discussion in 'Luthier's Guitar & Bass Technical Discussion' started by OiRogers, Mar 19, 2015.

  1. OiRogers

    OiRogers Member

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    Installed a 500k Audio taper volume pot into a LP for the neck pickup, prior owner had snapped half the top split off the old pot so no knobs were able to be mounted. Wiring was stock Gibson LP Standard wiring from '07.

    I put the new pot in and made all connections the same as the prior connection. All joins went quickly, even the grounding on the pot itself.

    I have also gone through a second time with my iron and made sure none of my joins are cold.

    Here is the problem: when full off I get sound like the pot is on 8 or higher, roll up toward "2"ish and sound is cut... Full off like you would expect from zero. Continue to roll up and it tapers up from nothing at "2" to expected full volume at 10. Tone control attached to that pot works as expected.
    Rolling down from 10 I get the same... Nice taper from 10 to 2 where it is full off. Then from 2 to 0 puts it back up to 8+ in volume.

    Did I fry the pot putting the ground on? :thud
    If not, any suggestions?
     
  2. walterw

    walterw Gold Supporting Member

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    yep, it's cooked, time to replace it :(
     
  3. Frenster

    Frenster Put your Rock Face on!

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    When soldering ground to pots, use the edges, not the center of back of the pot. Otherwise you bake plastic.
     
  4. OiRogers

    OiRogers Member

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    I did. :huh
    My ground is right on the edge lip.

    I had never baked a pot prior. Guess there's a first time for everything.:dunno

    Luckily, I have a couple spares sitting around.

    Thanks for the input all.
     
  5. Frenster

    Frenster Put your Rock Face on!

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    Sounds like you did it right. Maybe a bad pot to begin with.
     
  6. OiRogers

    OiRogers Member

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    As an update... pulled the pot and replaced with another longshaft 500k audio taper. Works as expected now.

    The pulled pot was new in wrapper from Gibson... pulled it apart and found no obvious signs of heat damage or other oddness.

    Guessing I had a bad pot. Never had run into one acting this way before.

    Thanks for the help you two, much appreciate the input.
     
  7. juh_sepp

    juh_sepp Member

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    Yeah.... I fried a volume pot this last weekend. First time for everything. Was able to confirm with the multi meter after I replaced it. Must be the season.
     

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