Simple Silicone Rubber Molds (no Parting Line)

Ideal for smaller projects (less than 12" x 12"), this is the easiest process for creating parts, patterns, tools, & molds. We demonstrate creating a silicone rubber mold and then the casting of parts with Repro, epoxy casting resins and polyurethane elastomers.

To see other mold making videos see

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    19 Discussions


    4 years ago on Introduction

    I have used Armorall for a release agent. Ajso works well for polymer clay polish.


    11 years ago on Introduction

    can this method and any of these resins be used to make climbing holds?? and how well will they hold up under repeated use and abuse??? Also what are we looking at price-wise for the supplies to do this??

    1 reply

    Yes - there are resins that could be used to make climbing holds. You'd probably want to embed some metal inserts and use a fiber-filled resin, but a little research should point you in the right direction. You could call the folks at and see what they say, and I would imagine you could do the same to Freeman Manufacturing (the makers of the video)


    Reply 7 years ago on Introduction as well as (the makers of the videos) sell both resins, fillers, urethanes and silicones- if you do a search for casting resin, RTV silicones, etc you should find a number of suppliers. Over the past few years, this stuff has gotten a LOT easier to obtain - and a lot easier to use.


    Reply 11 years ago on Introduction

    hardware and art supply stores can order this stuff if they don't already carry it


    Reply 7 years ago on Introduction

    Yes - polyurethane resin can be painted - as can most cast-able materials assuming you use the correct primer and paint. The important thing to keep in mind is to clean the parting compound off of the casting very thoroughly - or your paint will simply fail to bond. Don't ask how I know - lol.

    I've done a fair bit of casting, and I usually use a vaseline and naptha mixture. Dissolve some vaseline in about an equal amount of naptha, paint it on with a brush working it around to get a good even coat, let the naptha flash off and you'll have a very thin coat of vaseline which will work well as a parting compound.


    9 years ago on Introduction

    i Wonder if pam cooking spray would work instead of the releasing wax


    11 years ago on Introduction

    I concur. These are well done and make mold making seem accessible to even novices like me.