How to Make Resin Molds - Step by Step Tutorial


Molding is a common production process that involves pouring liquids, usually preheated, into the mold cavity. While the liquid cools, it hardens creating a new mold-like object. The newly created item, known as a mold is removed from the mold and used for other production processes or packaged and sold as the final product. However, resin casting is a unique casting process characterized by the use of synthetic resin.

How to make resin molds


Before You Get Started

1. When you start making molds, don’t forget to have all the tools you need and set up your work area neatly and cleanly.

2. Hair and particles like to sit on silicone, so always clean their surfaces before you start.

3. With clean hands, make sure that the surface you are working on is flat and level so that the silicone is evenly distributed.

4. Choose the right design. To achieve the result of a glossy surface, your original design should have a glossy surface, you can varnish or coat the surface design with a layer of resin and completely harden to the touch.

5. Choose the right housing for your design, taking into account enough space on the side and the depth of the final mold. This way you do not waste silicone filling unnecessary gaps and you have enough space so that the mold does not break due to the thin layer of silicone. The housing can be metal, hard plastic or cardboard.

6. When mixing silicon, use a 1: 1 weight ratio for best results.

7. While stirring, stir the silicon for at least 3 minutes, depending on the amount to mix well and reduce bubbles.

8. Be sure to wait for the mold to harden for at least 12 hours before using the resin.

9. Touch the silicon; it doesn’t matter if it’s a little sticky.

10. Never use direct heat on molds, burn them, and to clean with adhesive tape, clean the surface and gently clean the inside with soap and water if necessary.

Things You'll Need  

  • Silicone Rubber
  • Cookie cutters or cardboard(Border for your mold)
  • Items to be reproduced
  • A syringe (or something to measure)
  • Disposable plastic cups
  • Disposable gloves
  • Something you'll put in your resin (use colors, charms and flowers)
  • Straw
  • Packing tape, plastic sheets or anything similar(base for your mold)
  • Hot glue gun

    Step by Step Instructions

    At first glance, it probably seems very difficult to make a resin mold. With this step-by-step guide, even you as a beginner will have no problem creating a successful mold.

    Construction of the frame

    Step 1. Take the appropriate size of shell, glue the back side with resin tape and place it on a flat surface to work on. Carefully use a glue gun to glue and coat the edges of the case on the tape, which will ensure that silicon does not leak out of the case.

    Construction of the frame

    Step 2. Place your design correctly inside the case, face up, gluing the back to the resin strip and leaving enough space on the side for the silicone to be poured. You have now completed the first important part of mold preparation.

    Place your design correctly inside the frame

    Mixing the Silicone

    Step 3. You are now ready to mix the silicon to resin ratio of 1: 1. Carefully measure the weight of parts A and B and add them, stirring slowly for at least 3-5 minutes, scraping the sides with a wooden stick. This ensures better mixing and fewer bubbles that form inside. When you’re done mixing, you’re ready to tap.

    Silicone Pouring

    Step 4. Start slowly pouring the silicone into the mold, try to pour evenly and thinly holding the cup a little away from the mold, moving your hand inside the shell, gently covering the empty space first.

    Silicone Pouring

    Step 5. Allow the silicone to stand for at least 12 hours to harden. It may take a few more hours, but when it hits the surface, it should harden. It’s okay if it’s a little sticky. If your silicone does not harden properly, you did not follow the measurement and mixing steps properly.

    Extraction of the mold

    Step 6. To unmold, pick up the mold, peel off the glue gun and tape from the back side. Gently push the silicon mold out of the housing. Your Mold is now ready to use. You can use a blade or scissors to cut any excessive silicon covering the back of your molded piece to easily unmold it.

    Extraction of a finished silicone casting mold

    Different Types of Mold Making Materials

    There are many types of materials that you can use to produce molds, depending on how the original model will be carried out, in the way it will need reproduction and levels required details. Using these materials can run reproduction on products as diverse as plaster, plastic, cements and waxes. Here are the five most common molding materials so you can choose the best for your goal:

    Silicone Rubber

    To make a silicone mold yourself, you need a silicone rubber. This soft compound which lasts relatively quickly is available in specialist stores. After treatment, the silicone is elastic. Their fragility depends on the degree of hardness chosen. Excessive removal will cause cracks or fractures in the material.

    Which degree of toughness is best for you depend on your project and to some extent it is a matter of trial and error? The softer the material the easier it is to release the part from the mold. However, due to its high elasticity and low brittleness, the mold is very unstable. The opposite is true with a full mold: the parts are not so easy to unroll and care must be taken not to break the brittle silicone. However, high-value Shore molds are of course easier to handle because they are less mobile and do not warp as easily.

    Heat resistance as well as food safety is important if you want to bake or make chocolate with your own mold. Make sure it is heat resistant up to 200 ° C.

    Another criterion has to be verified, depending on the type of project: the chemical resistance of the material. It should also be strong if you work with epoxy resin, concrete or other fused materials.

    Can you find out if silicone meets your requirements by contacting your specialist distributor or by reviewing the data sheet?

    In addition to the silicone rubber, you will also need the frame itself and the blank you want to reproduce to produce a negative mold of the original shape. If, on the other hand, you want to work without the original mold, the frame is omitted and only needs empty.

    Polyurethane Rubber

    Like other mold production materials, polyurethane rubber is suitable for a series of casting parts, including plaster and concrete. With hardness similar to a pen with a hardness of 40a in coastal durometr, polyurethane rubber is a two-part tire which is an excellent option for heavy melting applications, such as industrial parts and departments. The lack of polyurethane rubber is to be based on the use of an unlocking agent to remove properly prepared models.


    Latex modeling is one of the most famous mold production applications, which regularly use departments for special effects of movies and television in the world. From silicone rubber, latex is in pre-vulcanized liquid form and dried at room temperature, which facilitates the creation of strong molds. You can dive the original model in latex or layers of latex on the material. As can be a process that spends a lot of time, there are other latex molding materials such as thickening to accelerate layers.

    Silicone Putty

    Silicone Putty is a platinum-cure two-part mold making material that comes in the form of two component putties that you mix together by hand to form a molding putty. You then shape this material over or around an object that you want to copy. The material will then cure to form a durable, flexible mold exactly duplicating the object you shaped it around. Silicone Putty Molds are easy to make, durable, food safe, and you can bake food or polymer clay in them.

    How to Form Silicone: Two-part Shapes

    Two-piece molds are used to produce a variety of items that are of particular interest to model manufacturers. This way, you can not only cast works of art from epoxy resin, but also parts of different materials and sizes. Molds can be used, for example, for plaster and concrete, but of course also for resin. The pieces of concrete or plaster can later be painted and decorated, thus making doors, bridge pillars or house facades. If you work with epoxy resin, you can make great items using two-piece molds, into which you can embed a variety of items, such as leaves and dried flowers.

    In addition to the materials mentioned above, you will also need plasticine. Push it into the frame so that it is half full. Make sure the corners are aligned and the surface is smooth.

    Now press the blank halfway into the plasticine and fill the mold with silicone rubber. Allow the material to harden, then remove the silicone mold and play the dough. However, the finished mold will immediately be put back into the frame as it will be used a second time.

    Place your white exactly in the space. Now cover the mold with Vaseline so that the two halves of the mold can be easily separated later. In the last step, pour the liquid silicone back into the frame and let it harden again.

    2 Pieces Mold Making Tutorial

    Silicone Molds with Cutouts

    Silicone molds with cutouts can be a big challenge when demolding. The cut blind parts have clearly visible corners and protruding edges and can be found in the way of removal from the mold. If these cuts are relatively small and you use soft silicone (shore 0-20), these edges should not be a major problem. Slightly more intricate will be the case with larger incisions. In this case, it is desirable to make a mold of two or even several parts. In any case, you should choose a soft flexible silicone rubber and pay special attention when removing items so as not to stretch too much.

    Frequently Asked Questions

    How to Clean Resin Molds?

    • Grab a piece of tape or lint roller and use them to get the majority of residue bits off. You could probably also use a little piece of blue tack or clay if you like.
    • Whatever you've got on hands we're going to wash the mold after this. Pop them into the sink with some warm soapy water and just gently give them a wash. Make sure the cavities are all clean as well.
    •  Instead of just letting it drip dry, you can take a piece of paper towel and blot off all the excess water and soapsuds because if you leave them on there to dry, it's going to leave marks on the mold. 
    • Don't ever leave your molds directly in the sunlight because that will start to break down the silicone and ruin them.

    Are Silicone Molds Reusable?

    There’s nothing better than silicone rubber if one wants to make reliable and long-lasting moulds. It is really second-to-none for reproducing detail, in addition to having the ideal combination of flexibility and strength. But silicone rubber isn’t cheap, averaging about $25 per lb. and unlike many other materials there are no ‘cut-price’ versions.

    The first time mold making was not that easy, especially cut in zig zag line and seal it up well. But it's worthy when you're capable of making a resin mold of everything!

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