How to replace pots on vintage silverface amp

Discussion in 'Shock Brother's DIY Amps' started by jjk1407, Jul 24, 2021.

  1. Boreas

    Boreas Poster Extraordinaire Silver Supporter

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    That makes the most sense. Turkey principle.

    Easy enough to check. Perhaps OP could post his ESL (Exposed Shaft Length) and others with "normal" plates could post their ESLs. Should be off by the thickness of a nut.
     
    Last edited: Jul 26, 2021
  2. Lowerleftcoast

    Lowerleftcoast Friend of Leo's

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    but.. they could have made up for the length of the shaft with the nut on the other side of the brass plate.

    Why, oh why, in between the chassis and plate??? Weird wild wacky stuff!
     
  3. corliss1

    corliss1 Poster Extraordinaire Platinum Supporter

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    Marshall and Sovtek both did this where all pots were assembled to a metal strip, then placed on the board/amp at the same time, so it's not totally unheard of. Maybe the OP just found a weird segment of Fender history where they tried this for a brief period. It really does seem to make the most sense that this was factory work, but since no one else has heard of it.............................................................................................
     
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  4. Archtops

    Archtops Tele-Meister

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    Good job on the repair. Sounds like a rare design for the time.
     
  5. Boreas

    Boreas Poster Extraordinaire Silver Supporter

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    Mebbe a newbie thought it was a good idea. Luckily Lupe beat him into submission.
     
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  6. mherrcat

    mherrcat Tele-Holic

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    I believe those pots have carbon elements, so the DeoxIT "D" series products may not be the best thing to use on them. I would use something like DeoxIT F5 for faders. I think the "D" series product is intended more for metal-on-metal contacts.
     
  7. jjk1407

    jjk1407 TDPRI Member

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    The original pot shafts are in standard length - 3/8", or even a tad shorter than that. So... yeh, can't think of any reason for this procedure.

    Maybe a newbie in Fender invented this method and later joined Marshall/Sovtek? :lol:

    Probably worth to mention that there aren't any extra nuts on the switches and the input jacks. The brass plate is bent and touches the chassis around those points.
     
  8. King Fan

    King Fan Poster Extraordinaire Ad Free Member

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    I'm guessing there was some really heavy weed in California by 1973... :)
     
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  9. Lowerleftcoast

    Lowerleftcoast Friend of Leo's

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    Not much goin' on in '73... cough. As I recall there was a huge cloud of smoke over the midwest and you didn't need a weatherman to know which way the wind...

    '73... Well I guess Frank Sinatra / Ol' Blue Eyes Is Back...hit the chart
    and National Lampoon / Lemmings came out.

    Elvis did his Hawaiian thing. Marvin Gaye / Let's Get It On, and Alice Cooper / Muscle Of Love, Diana Ross / Touch Me In The Morning, Sly & The Family Stone / Fresh, Carole King / Fantasy... had the love thing covered.

    But you asked about midnight tokin'... So Bob Marley / Burnin' and Catch a Fire, John Denver / Rocky Mountain High, Joe Walsh / The Smoker You Drink, The Player You Get, Steve Miller Band / The Joker, Steely Dan / Countdown to Ecstasy

    Then a few of these bands came through town...
    Bob Dylan
    ZZ Top
    Free
    Jackson Browne
    Traffic
    Sly & The Family Stone
    The Faces
    Leon Russell
    Neil Young
    Alice Cooper
    Mott The Hoople
    Roxy Music
    Iggy Pop
    Procol Harum
    Mahavishnu Orchestra
    Rick Wakeman
    The Doobie Brothers
    Uriah Heep
    America
    Focus
    Eagles
    Santana
    Ten Years After
    Lynyrd Skynyrd
    Yes
    Bruce Springsteen
    Grand Funk Railroad
    Genesis
    Black Sabbath
    David Bowie
    Deep Purple
    Emerson, Lake & Palmer
    Chicago
    Jethro Tull
    The Who
    The Allman Brothers Band
    Wings
    Stevie Wonder
    Mike Oldfield
    Elton John
    The Rolling Stones
    Led Zeppelin and
    Pink Floyd.

    ...and then Cal Jam in '74... welcome back my friends it's the show that never ends...
    ...and then Police Chief Davis in '75 at the Pink Floyd concert... everyone frisked on the way in... ...scariest and maybe the best concert I have ever been to... pass that over here... cough. Gilmour said that was a new song they were working on called "Dogs"... huh...
     
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  10. King Fan

    King Fan Poster Extraordinaire Ad Free Member

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    Whoa, I never thought I'd see a tribute to 1973. Well done.

    I'm afraid my impression of that year has always been sorta like, um, (consults Wikipedia):

    Nixon sworn in for second term
    Paris Peace Accords signed in January but
    Bombing of Cambodia continues until August
    CIA sponsors coup in Chile
    Wounded Knee, Watergate, etc.
    Oil Crisis triggers long lines at gas stations,
    devaluation of dollar,
    inflation,
    recession,
    and 'national malaise' that would last through the '70s​
    And, worst of all, really ugly superwide bellbottoms become dominant fashion trend...

    :):):)

    OK, sure, it was a good year in music, but still, I see the number 1 hit of the year was "Tie a Yellow Ribbon Round the Old Oak Tree."
     
  11. schmee

    schmee Doctor of Teleocity Ad Free Member

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    It'll be easier to put a $5 pot in than try to figure it out. You'll know then.
    Normally, The inner nut should be sandwich the brass plate, chassis and face plate between it and the outer nut, I doubt it is between the brass and the chassis. I allows you to make the knobs on the front not jut out at different lengths. There should be s star washer between that inner nut and the brass plate to keep the pot from turning.
    It appears you have something odd there. Were they using that nut to use a small diameter pot in a larger hole? Never ever seen that.
    I have had 67, 68, 69, 70, 71, 73, 74 and later SF Fender amps NONE had that. Is this an UL amp by any chance?
     
    Last edited: Jul 27, 2021
  12. jjk1407

    jjk1407 TDPRI Member

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    Yeh, that's what I did ;) trying it out.

    The inner nut on mine is between the brass plate and the chassis, to mount the pot to the brass plate. The pots/holes look all normal, and I verified that all the pots are dated back to 73 CTS, so unlikely a later mod happened here. Can't think of any logical reason why it was built like that...
     
    Last edited: Jul 27, 2021
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