We have determined that most transoms are 1.5" thick, but for other sizes, you can use a Seacast™ Spacer Bar, cut to any thickness you need. Our spacers are designed to maintain a consistent gap opening to avoid bulging and/or collapsing of weak skins.
Our spacers are made from Seacast™ and will bond to itself with no cold seam. Note: Use only a poly-based glue to adhere spacers within or simply clamp in place before pouring. No Silicone or Epoxy.
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