Limited Use Foam Hole-Formers

  • Great for Limited-Run Productions
  • Low-Cost Hole-Former / Knockout Alternative
  • Available in Flat Wall, Clyindrical Wall, Full Sheets
  • Mounting Magnets Available


18″ dia. Parallel Foam Hole for 6″ Wall x 60″ I.D.
(Functional for VORTEX manholes)


64″ dia. Foam Hole for 9″ Wall x 96″ I.D.
(“Custom Cut” for Split-Barrel Application)


2″ PVC and 4″ PVC Septi-Seal Gaskets on “Ready-To-Pour” Foam Mandrels


89″ dia. hole in a 96″ I.D. manhole base

Created with a Foam Hole-Former made by Blackthorn!

CUSTOM 92″ Offset Corner Foam Hole-Former (on pallet ready to ship)


Challenge: Needed a One-Time Use Mold for the base of a column…


Solution: Mold made of Multi-layered Foam