Vintage MXR pedal - deteriorating foam

Discussion in 'Effects, Pedals, Strings & Things' started by popvulture, Apr 30, 2015.

  1. popvulture

    popvulture Member

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    I've got a vintage script Phase 100 that sounds incredible... every time I open it though, I wonder about the deteriorating foam inside. Can that stuff have negative effects on the circuit? Some of it's come off the baseplate side and is now sticking to the capacitors, etc.

    Maybe this isn't anything to worry about, but if there's something I should do, I'd love some suggestions. This pedal is the tits, and I'd be pretty bummed if something preventable were to happen to it.
     
  2. Totally Bored

    Totally Bored Member

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    It still sounds good right :dude



    I say no.
     
  3. dconeill

    dconeill Member

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    Buy some foam and replace the foam that's in the pedal?

    The plasticizers in foam evaporate eventually, which causes the foam to become brittle and to crumble.
     
  4. popvulture

    popvulture Member

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    Yeah it still sounds amazing! I was just worried about the possibility of something stupid happening, like the foam crumbles somehow damage the circuit.

    What can I say - I come from a long line of worriers.
     
  5. popvulture

    popvulture Member

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    I was thinking I could scrape it off or something, but that would be kind of a pain in the arse...
     
  6. Totally Bored

    Totally Bored Member

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    The crappy foam is part of the mojo and sound. Think like that and you'll be good :aok
     
  7. Black_Label

    Black_Label Member

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    Yeh, you should try and replace it. Over time that foam gets all stuck on the board as it deteriorates and can lead to problems and/or interrupted connections. It sounds great now, but that will change as the foam keeps disintegrating.

    Be careful when you're removing it. If you scrape it off, you can break connections on the board so it's best to pluck it off bit by bit with tweezers. You can replace with foam or plastic or cardboard - just something that keeps the components from grounding against the backplate.
     
  8. boppy

    boppy Member

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    I can't remember where exactly, but I read a post recently about issues with a vintage MXR pedal after the owner decided to do away with the gnarly disintegrating foam.

    I have an original M117 Flanger which I peeked into. The foam is crumbly, but it doesn't seem to be doing any harm--hell, it might even contribute to the sonic awesomeness for all I know.

    If it aint broke, don't fix it, right?
     
  9. Alchemy Audio

    Alchemy Audio Silver Supporting Member

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    I've had to clean several vintage MXR pedals that have come through the shop for repair or TLC. I've had success spraying the circuit board with contact cleaner and (gently!) using a soft bristle tooth brush. After removing as much of the decaying foam as possible, thoroughly dry the circuit board with compressed air. Other than making a mess, I've never known the decaying foam to have any adverse affects on the tone or performance of the pedal. I usually cut a business card to size as a solution to prevent the circuit components from shorting out on the enclosure. MXR still uses this foam in their "script" model reissue pedals.
     

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