Activity Feed Forums Sign Making Discussions General Sign Topics ACM composite to fixing adhesive, advice needed please?

  • Robert Lambie

    Administrator
    October 7, 2020 at 10:05 am

    It can depend on a few things Jamie.

    The adhesive, normally two-part adhesives heat up a lot to enable them to cure.
    this reacts with the core of the ACM and creates the dimple.
    If you use an adhesive that doesn’t heat up so much, it helps prevent it.
    however, if you are using a cheaper brand ACM or if you’re using a “lite” version of the ACM the aluminium face skin is thinner, making it easier for the reaction to happen to the heat. hope that makes sense.

    • Jamie Palmer

      Member
      October 7, 2020 at 5:42 pm

      Thank you, just such a shame when everything looks great to be let down by the pesky dimples. Was thinking of routing a load of circles pre glueing to locators then using vhb tape with primer to the letter, but think I will test a few different glues also

  • Frederick McLean

    Member
    October 7, 2020 at 3:13 pm

    Think it was 3M scotchweld acrylic 8805 we used last time, seeminglt doesnt produce heat in the chemical reaction(or not a lot)

    • Jamie Palmer

      Member
      October 7, 2020 at 5:39 pm

      Thanks will take look at this

  • Robert Lambie

    Administrator
    October 7, 2020 at 8:46 pm

    It is the 3M scotch weld that we use also, but I forget the number as there are various versions of it. I only use the premium versions of DiBond, Skybond or Rynabond and I don’t have any problems with dimpling. Just be sure to check that whatever you use isn’t heating up so much it causes a reaction.