To help beginners make silicone molds, the tools and materials that may be used in the mold making process are listed below. You can choose and prepare according to your actual situation.
Materials
1. Mold Making Materials
This is the main material for making silicone molds, usually RTV-2 silicone rubber raw material, and there are two common types: tin-cured silicone and platinum-cured silicone. It is usually divided into two parts, which must be mixed together immediately before use.
2. Casting materials
The material poured into the silicone mold can be polyurethane resin, ABS, PP, plaster, epoxy resin, polyester resin, concrete, etc.
3. Silicone Thinner
Thinner has a unique role in your mixing. It will thin the solution if it develops into some considerable thickness.
4. Silicone Thickener
It is the opposite of thinner. In case you need a durable and sturdier silicone mold, then involve a thickener. Be careful not to add too much, or you could end up ruining your mix and having to start from scratch.
5. Silicone Pigments
Adding a little dye to your mold can give it a unique look and aesthetic. If you’re making a customized ice cube tray, consider throwing in a little dye so it doesn’t become an eyesore in your freezer.
6. A master pattern (also known as the mother mould)
The master pattern is the original object that you will duplicate using the silicone mold. A master pattern can be an existing object like a plastic toy, or a newly made item fabricated using e.g. a 3D printer.
Tools
1. Mold Wall Materials
Mold retaining walls, also known as 'forms' or 'boxes', are used to create the support structure that the mold material is poured into. Common materials are: Corrugated sheet plastic (or foam core in a pinch), Acrylic/Plexiglass Sheets, Styrene or thin clear polycarbonate sheets, Corrugated Sheet Plastic, LEGOS.
2. Mixing Containers
The plastic mixing container with measurement mark is the best choice, which can bring you great convenience for measurement. which should be larger than the master pattern.
3. Stir Sticks
Disposable stir sticks are necessary for all material mixing, Different amounts and types of mold and casting material will require different shapes and sizes sticks!
4. Vacuum Pump
Liquid Silicones with a viscosity above 10,000 cps should be vacuumed to avoid air entrapment and bubbles in the finished mold. Degasing generally lasts several minutes and at least until the bubbles stop rising regularly to the surface when the vacuum is released. However, prolonged degasing can cause loss of certain components that are required for curing. The RTV liquid silicone will expand under the action of the vacuum and it is therefore necessary to have a container of appropriate size.
5. Digital Weight Scale
Used to accurately weigh the mixed materials part A and part B. Most rtv-2 silicone mixtures are determined by weight, not volume. If the AB ratio differs too much, it may not cure or cure too quickly.
6. Release Agents
Sometimes it's necessary to add a mold release to a model before pouring on the mold material – or to the first half of a mold when making a two part mold so the two halves don't stick together. Materials that can be used as mold release agents: cooking oil, silicone fluids, petroleum jelly. Never use too much release agent, this can lead to a porous and greasy surface of your casting.
7. Clay
Clay is only required when making a two-part mold. If you are using platinum-cured silicone, remember to use sulphur-free sculpting clay, This oil based clay is sulphur-free so that it won't interfere with the curing process of platinum based silicone rubbers.
8. Glue Gun & Glue Sticks
The hot glue gun definitely wins the award for the most versatile tool in the making/crafting world. For our purposes, we'll use it to secure models and mold walls to mold boards.
9. Disposable Gloves
Wear gloves and, if necessary, a suitable mouth mask, safety goggles and any additional protection! Platinum-cure silicone rubbers are critically sensitive to sulfur or amines and will not cure under any circumstances when exposed. You cant use latex gloves while mixing them, make sure you use Nitrile or Vinyl gloves.
