How much Epoxy (JBWeld) needed for a pair of speakers?

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Comments

  • gdb
    gdb Posts: 6,012
    edited June 2012
    Not really, (IMO) as there's no other scenario to cause a freeze up unless the VC swells up/mushrooms out of shape from bottoming out and then, wedges itself somehow. I have always found it's the pole piece or the magnet's glue has failed and allowed things to shift/pinch/freeze. The drawing below pretty closely approximates a Polk 6.5" MW driver's layout.

    spkr-cross-sect-theile.gif
  • Mystery
    Mystery Posts: 2,546
    edited June 2012
    gdb wrote: »
    Not really, (IMO) as there's no other scenario to cause a freeze up unless the VC swells up/mushrooms out of shape from bottoming out and then, wedges itself somehow. I have always found it's the pole piece or the magnet's glue has failed and allowed things to shift/pinch/freeze. The drawing below pretty closely approximates a Polk 6.5" MW driver's layout.

    spkr-cross-sect-theile.gif

    Thanks for the detailed image gdb.
    My assumptions were exactly that until I saw the frozen driver I mentioned that is perfect in every way visually and physically from outside and still frozen. It could be something messed up in the voice coil then. The S8 pair was from a thrift store and this one was frozen and it's cabinet was horrible suggesting they got dropped/dragged etc... but magnet assembly and magnet are where they should be.

    Looking at the picture, epoxy should be applied between magnet and magnet assembly top/bottom.
    Does it make sense to apply between the magnet assembly and basket where they meet or are close?
    Some have small gap between the basket and magnet assembly and if not needed, I won't do it as there is a risk of epoxy seeping inside.
    Thanks again.

    Klipsch RB81, KG3.5, B&W DM602.5, Polk.
    Subwoofers: Klipsch RW10, Triad ProSub Bronze.
  • gdb
    gdb Posts: 6,012
    edited June 2012
    Some assemblies are riveted while others are merely glued. (badly) If you have any that are not riveted, glue em. IMO anyway. :wink:
  • mstrane21
    mstrane21 Posts: 2
    edited February 2018
    Hi.... so instead of starting a new thread, I will bump this ancient topic since it is germane to my question. I recently acquired a pair of RTA-12 C's and Monitor 7's for dirt cheap. I have read the horror stories about magnet shifting, and applied some JB Weld around the perimeter of each side of the magnets. But did I put enough on there? I feel like maybe I didn't slather it on enough. I know it looks sloppy, but that stuff is not very easy to work with, especially for a first-timer. Any opinions are welcome. Thank you. Mike32415d6hc1fr.jpg
    2jsnarnoxl7u.jpg
  • F1nut
    F1nut Posts: 49,708
    Anything is better than nothing.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • @mstrane21 Those look good to me. I have only ever put on slightly more than that myself when using JB weld. Since you went all the way around, both top and bottom I think you would have to abuse it pretty badly to get the magnet to move on you.

    Now... on to Dynamat... :smile:
  • @mstrane21 Those look good to me. I have only ever put on slightly more than that myself when using JB weld. Since you went all the way around, both top and bottom I think you would have to abuse it pretty badly to get the magnet to move on you.

    Now... on to Dynamat... :smile:

    Thank you for the reply! That puts me at ease

    Not sure I will keep the 12C's due to their huge size relative to my space so I likely won't Dynamat 'em just yet!