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Mold/pattern release material

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  • Mold/pattern release material

    I need some ideas for a release material to use between a steel plug and JB Weld. I want a close fit when the plug is removed and the part is inserted.

    Thanks in advance


  • #2
    Use the directions on the JB Weld tube as a guide. If it reads:
    Surface must be free of oil, grease, wax, dirt and dust.
    then try using one of those.
    Location: Long Island, N.Y.


    • #3
      Silicone mould release, dry ptfe, soap, washing liquid, Vaseline, just a few.
      Completely summed up already lol


      • #4
        PAM cooking spray. Works as an anti-spatter spray for welding too.

        This works good too.
        Last edited by Highpower; 05-26-2017, 04:34 PM. Reason: added link


        • #5
          The acraglas release product is an alcohol based vinyl product that, when dry, has a measurable thickness, and when your epoxy is cured can be scraped off of both the epoxy and what it's been painted onto. At one time they had an aerosol PTFE release agent that worked well when you remembered to shake the can well...not so well when you forgot!
          David Kaiser
          “You can have peace. Or you can have freedom. Don't ever count on having both at once.”
          ― Robert A. Heinlein


          • #6
            carnauba wax without grit, PVA (poly vinyl alcohol)
            Sole proprietor of Acme Buggy Whips Ltd.
            Specialty products for beating dead horses.


            • #7
              As stated above, PVA and/or wax. Both are used as release films for making composites with epoxy.


              • #8
                While there are many things that will work, I prefer PVA. It does have a thickness, which allows for some flex when you are trying to separate the parts- not much, but more than the silicone or teflon coatings.

                I very often have used a simple, easy to find mold release- you actually carry it with you at all times, even when you're completely naked- it's hair oil. I'll rub a finger just above my forehead and into the hair, or behind my ears, then transfer that to the mold. Two applications usually do the trick. People have laughed at me for doing that, but I have the last laugh. It does work, try it.
                I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-


                • #9
                  SInce we are talking about a specific product, I found this on

                  1) J-B Weld will not adhere or bond well to:

                  Any flexible rubber surface
                  Polypropylene plastic
                  Polyethylene plastic

                  2a) What can I use as a surface cleaner before using J-B Weld?
                  We recommend using acetone or lacquer thinner. In the absence of these two, soap and water can be used. Just be sure that the surface is completely dry before applying J-B Weld. DO NOT use alcohol or any “cleaner” that will leave a petroleum residue.
                  2b) Is J-B Weld resistant to water and/or gasoline?
                  When fully cured, J-B Weld is completely resistant to water, gasoline, and about every other petroleum product or automotive chemical.

                  Which suggests that an oil will work without impacting the cured product.

                  At the end of the project, there is a profound difference between spare parts and left over parts.

                  Location: SF East Bay.


                  • #10
                    The go-to release agent when glass bedding rifle stocks is KIWI neutral shoe polish. I've used it many times on custom rifles. It releases easily and has negligible thickness.


                    • #11
                      I forgot about shoe polish- that does work also.
                      I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-


                      • #12
                        Renaissance Wax works well as it goes on so very thin.