Review on Black POR-15 Patch - 4 oz Filler & Seam Sealer with Ultimate Adhesive Properties - Repairs Holes, Cracks in Steel, Wood, and select Plastics - Reinforces Weakened Metal by Jason Melvin

Wow, that's the kind of stuff you'd want in a tube just to play with. Applies and dries absolutely BLACK. Brilliant when dry. Hard as a rock. Perfect for filling in my sloppy welds (no comment) when I paint over. I used it to fill the end of a 1/4" x 3/4" pipe on a project as welding would have been a project in itself and it was by far the right answer. Mold-dried, hard and absolutely unbreakable after hardening. Feels hard like steel. After sanding I painted the project (POR-15) and the pipe ends looked great as part of the steel. Warning - wear gloves like POR-15, it will stay on our hands for a while. Long time.