Mold Star™ Platinum Cure Silicone

Buy Smooth-On at FormX

Smooth-On is one of the world’s leading manufacturers of 3D modeling materials such as mold-making, casting and special effects materials, as well as industrial casting resins, adhesives and equipment. FormX is the main distributor of Smooth-On products in Europe.

Smooth On

Mold Star™ silicones cure to soft, strong rubbers which are tear resistant and exhibit very low long term shrinkage. Molds made with Mold Star™ will last a long time in your mold library and are good for casting wax, gypsum, resins, and other materials. Cured Mold Star™ rubber is heat resistant up to 232°C and is suitable for casting low-temperature melt metal alloys.

One to One Mix Ratio - Mold Star™ rubbers are mixed 1A:1B by volume (no weighing scale necessary) for precise measurements even at a very low mass and cure at room temperature with negligible shrinkage.

No Vacuum Degassing - Mold Star™ silicones feature relatively low viscosities making vacuum degassing optional and is not required for most applications. A uniform flow will help minimize entrapped air.

Translucent Options -Make Fast Cut Molds or Castings Mold Star™14T, 19T, 20T, and 31T are translucent silicones for making fast molds or casting into alginate molds. They offer fast cure times, multiple hardnesses, and an infinite number of color effects achieved by adding Silc Pig™ silicone pigments or Cast Magic™ effects powders.

Products

Mold Star™ 14T Mold Star™ 14T ... € 28.48 Buy now Mold Star™ 15 SLOW Mold Star™ 15 SLOW ... € 879.66 Buy now Mold Star™ 40T Mold Star™ 40T ... € 28.92 Buy now Mold Star™ 31T Mold Star™ 31T ... € 26.11 Buy now Mold Star™ 30 Mold Star™ 30 ... € 955.74 Buy now Mold Star™ 16 FAST Mold Star™ 16 FAST ... € 20.94 Buy now Mold Star™ 19T Mold Star™ 19T ... € 26.38 Buy now Mold Star™ 20T Mold Star™ 20T ... € 25.58 Buy now

Video’s

Youtube video 8HyVCVfZ_g8

Youtube video FQ1A7ZjTsx8

Youtube video lTtWPq1LHec

Youtube video N2yPHzspR90

Instructions

Note: This product will not cure against surfaces containing sulfur, even when sealed.

Cure Inhibition - Addition cured silicone rubber may be inhibited by certain contaminants in or on the pattern to be molded resulting in tackiness at the pattern interface or a total lack of cure throughout the mold. Latex, sulfur clays, certain wood surfaces, newly cast polyester, epoxy or urethane rubber may cause inhibition. If compatibility between the rubber and the surface is a concern, a small-scale test is recommended. Apply a small amount of rubber onto a non-critical area of the pattern. Inhibition has occurred if the rubber is gummy or uncured after the recommended cure time has passed. To prevent inhibition, one or more coatings of a clear acrylic lacquer applied to the model surface is usually effective. Allow any sealer to thoroughly dry before applying rubber.

If you are not sure if your clay contains sulfur, do a small compatibility test before using for an important project.

Applying A Release Agent - Although not usually necessary, a release agent will make demolding easier when casting into most surfaces. Ease Release™ 200 is a proven release agent for releasing silicone from silicone or other surfaces. Mann Ease Release™ products are available from form x

Because no two applications are quite the same, a small test application to determine suitability for your project is recommended if performance of this material is in question.

Measuring & Mixing - Before you begin, pre-mix Part A and Part B separately. After dispensing required amounts of Parts A and B into mixing container (1A:1B by volume), mix thoroughly making sure that you scrape the sides and bottom of the mixing container several times. The rubber should be a uniform color with no streaks.

Optional… Vacuum Degassing - Although not necessary, vacuum degassing helps eliminate any entrapped air in pourable silicone rubber. After mixing parts A and B, vacuum material for 2-3 minutes at 0,98 bar, making sure that you leave enough room in container for product expansion.

Pouring - For best results, pour your mixture in a single spot at the lowest point of the containment field. Let the rubber seek its own level. A uniform flow will help minimize entrapped air. If using as a mold material, the liquid rubber should level off at least 1.3 cm over the highest point of the model surface.

Heat Curing - Time to demold can be reduced by applying mild heat. Adding an appropriate amount of Plat-Cat™ cure accelerator will also reduce demold time. The pot life and cure times can be extended using Slo-Jo™ cure retarder. Do not cure rubber where temperature is less than 18°C.

Mold Performance & Storage - The physical life of the mold depends on how you use it (materials cast, frequency, etc.). Casting abrasive materials such as concrete can quickly erode mold detail, while casting non-abrasive materials (wax) will not affect mold detail. Before storing, the mold should be cleaned with a soap solution and wiped fully dry. Two part (or more) molds should be assembled. Molds should be stored on a level surface in a cool, dry environment.

Safety - Use in a properly ventilated area (“room size” ventilation). Wear safety glasses, long sleeves and rubber gloves to minimize contamination risk. Wear vinyl gloves only. Latex gloves will inhibit the cure of the rubber. Store and use material at room temperature (23°C). Warmer temperatures will drastically reduce working time and cure time. Storing material at warmer temperatures will also reduce the usable shelf life of unused material. These products have a limited shelf life and should be used as soon as possible.

You may also need..

  • Mixing Beakers
  • Measuring Cups & Jars
  • Weighting devices
  • Brushes
  • Protective gear
  • Release agents

Mixing, Measuring & Weighing

Mixingcup Mixingcup ... € 0.53 Buy now Wooden Tongue spatula Wooden Tongue spatula ... € 2.83 Buy now Colad Turbomixer Colad Turbomixer ... € 50.73 Buy now Flexible mixing bowl Flexible mixing bowl ... € 15.98 Buy now Colad Turbomixer Colad Turbomixer ... € 50.73 Buy now

Brushes

Brushes Disposable Brushes Disposable ... € 0.76 Buy now Brushes Flat for Paint Brushes Flat for Paint ... € 2.15 Buy now Brushes for Polyester Brushes for Polyester ... € 2.90 Buy now

Protective Equipment

Stenchmask Stenchmask ... € 4.47 Buy now 3M Halfmask 3M Halfmask ... € 33.66 Buy now 3M Halfmask full 3M Halfmask full ... € 41.76 Buy now Glove Nitrile Glove Nitrile ... € 9.10 Buy now 3M Safety Glasses 3M Safety Glasses ... € 12.55 Buy now

Release Agents

Ease Release™ 500 Ease Release™ 500 ... € 18.43 Buy now Ease Release™ 2831 Ease Release™ 2831 ... € 64.47 Buy now ACMOS 82-2405 ACMOS 82-2405 ... € 17.05 Buy now Kwikee™ Sprayer Kwikee™ Sprayer ... € 138.38 Buy now Universal™ Mold Release Universal™ Mold Release ... € 15.26 Buy now

Why buy at FormX?

  • Dedication to Materials

    Dedication to Materials icon

    For over thirty years we have sought out the highest quality modelling, moulding and casting materials from around the world.

  • Inspiring + Unique

    Inspiring + Unique icon

    From silicones and resins to Jesmonite and special effects materials — a curated range for professionals, artists and makers.

  • Expert Advice

    Expert Advice icon

    Our sales team is widely known for their knowledge and dedication, supporting you in mould making, casting, sculpture and prototyping.

  • Shipping Across Europe

    Shipping Across Europe icon

    We ship from our warehouses in Amsterdam, Barcelona and Madrid to customers throughout Europe, from Greece up to Norway.

  • Amsterdam Original

    Amsterdam Original icon

    Founded in Amsterdam, FormX grew from a local art foundry into a major European supplier — with our roots firmly in the city.

Visa logo iDeal logo Mastercard logo Paypal logo FedEx logo DPD logo GLS logo
This website has been developed by Usecue B.V.
© 2026 FormX B.V.