Most of these materials can be cast in either polyurethane or silicone molds; the options mentioned above are general recommendations based on popular preference. Based on the section below, you may decide on a different option.
First, if the model is a human being or animal, careful consideration and investigation into appropriate skin-safe mold materials needs to be completed. Mold materials such as Skin-Wax, Hydrogel, or PlatSil Gels (a platinum-silicone rubber) may be viable options.
Certain mold rubber materials will suffer from cure inhibition (i.e., failure of a compound to cure against a surface within the recommended cure time) when applied to particular model materials. For instance, platinum-cured silicones will not cure properly when poured over sulfur-containing clay. They can also suffer from cure inhibition when applied to certain plastics (e.g., some plastics used in 3-D printing), polyester resins, some epoxy resins and any model that has had tin-cured silicone rubber or latex rubber applied to it in the past.
No matter what the mold material is, there is always a chance that a model could get damaged in some way during the mold making process. Using silicone rubbers may eliminate the need for release agents (which have the potential to affect the model); however, the oils from silicone rubbers also have the potential to affect the model in some way. It is recommended to always perform a small test cure on the model before making the entire mold.
CopyFlex is a food grade, liquid silicone rubber that was designed specifically for mold making. Unlike many liquid silicones that have complicated mix ratios and very thick consistencies, CopyFlex is easy to use because equal amounts of both catalyst and base are combined to produce a silky smooth, low viscosity liquid silicone rubber that reproduces the finest details. A 1:1 mix ratio is very convenient for large projects and also enables moldmakers to easily pour molds that may weigh as little as two ounces. Conventional liquid silicone mold making rubber often has a cure time of 24 to 36 hours which is very long when compared to CopyFlex which will cure in four hours at 70 degrees F.
It may surprise you to know that almost half of our mold making customers purchase CopyFlex for use with non-food materials. Reasons given are ease of use, high quality from a platinum based curing system and the peace of mind that comes from using a liquid silicone rubber that is not harmful, toxic or emits dangerous fumes.
EnvironMolds offers a great selection of high quality silicone mold rubbers. The silicone rubber materials enable you to easily make your own silicone molds from our mold making silicone rubber. We offer a silicone rubber mold making material for almost any application. Please read about the families of silcone rubber here so you can shoose the correct product. Our standard silicone mold rubber is MoldRite 25 good for most general silicone mold making for traditional silicone molds. We also offer a translucent silicone mold rubber called SkinRite 10 which can be tinted and used for special effects and applications to duplicate skin surfaces. This soft translucent rubber is perfect for realistic mask making as well as dolls. Then there is LifeRite, a silicone rubber safe to use on the skin in life casting and duplicating body parts. However, we also offer a food safe FDA approved silicone mold making rubber called, BakeSil, for food molds and baking containers. For faster acting silicone mold making we suggest using our 5-Minute Mold Putty. There are two families of silicones; 1) condensation cure and 2) addition cure. To understand the difference click here.
The best way to make sure your mold is watertight is to add a kind of thick-ish layer of silicone to the surface area of your object. Note how the dinosaur is padded by about a 1/2\" layer of silicone all around its body. Also, I have left a considerable amount of the dinosaur uncovered, as I am only casting half of this figure.
Hello I really want your helpI'm searching for a long time for the right way to make the soft silicone gel at home that's used in mousepads wrist restUsual guides like water and soap make it thick not soft like i wanted itI will be very thankful for your help
I actually can't buy things online I have to ask some sellers around me get the materials I want I'm wondering what should I get a silicone rubber 2 part a & b or a 100% silicon tube like this guideI discovered that i was testing on a regular silicone tubeSo what should I get
So to avoid only doing half at a time or not getting a full design mold we use a square container larger than the object we intend to mold. For instance the dino in the picture we would use a solid square box something that will hold the entire project and come up above the object on top. Then when hardened as a square you cut the silicone mold in half all the way around. We make candles and even liquid plastic replicas etc. We fill both sides with wax and let them start to harden but not solidify. Then once hard enough we place the two halves together and they will harden as a solid piece. Now if your using say liquid plastic and such you should try to put them together as soon as possible without it falling out or you'll find you have to add glue or adhesive to adhere them together. We've made some amazing candles using two part silicone molds.
Not really... There is no way I can make molds to suit everyone's needs. Several people have asked for special pieces such as skulls, doors, tombstones and other items that I may not get around to making. Creating your own pieces and molding them can be fun and rewarding.
Besides, making exact blocks (within 1/1000ths of an inch) is fairly time consuming, not to mention shrinkage factors and other silicone problems. I doubt there will be very many people out there willing to repeat all the work I've done to make a mold they could easily buy.
Please note that my Castlemolds(TM) and all of the pieces made from the molds are copyrighted by Bruce Hirst (me). I give permission for anyone to sell models using blocks made from my molds. However, there are some restrictions so be sure and read my Legal Statement before you do. I even allow people to make molds of finished pieces such as large walls and stairways for your personal use only.
However, if you start selling molds made from my pieces you're violating the copyright and breaking the law. By the way, if you do sell models made from my molds, I would appreciate some mention of my web site somewhere.
Latex mold making compound costs around $10 for a pint, and you can find it at most any craft or model railroad shop. It's mostly used to make rock texture molds for model railroads. It's fairly cheap, it cleans up with water, and you don't have to use a lot to make tall skinny items like statues.
I'm going to make a mold of this caulking tube spout. These will end up being spikes for the top of a tower. I've glued the spout down to a piece of plexiglass to make it easier to handle.This material is fairly thick, about the consistency of catsup. They make it thick so it takes fewer coats to cover an object.2.Thin the material down with water until it's the consistency of heavy cream. Paint the material over your object and remove any air bubbles that form on the surface by blowing on it.3.Let the first coat dry completely (about 4 hrs). The second coat is full strength. You should put at least 4 coats (letting it dry completely between coats) for a complete mold.When finished, peel off the coat of rubber. Because of the drying time, it will take around 2 days to make a mold.4.One problem with this type of mold is how you hold it upright to cast items with it (I used Legos).When casting items, you may have to coat the inside of the mold with mold release compound occasionally. Overall, I don't like using latex material.Silicone RTV Moldmaking CompoundSilicone RTV (room temperature vulcanizing) mold making rubber is the best choice for making molds. Below are some instructions on how to use this material to make molds. At the end of this article I will list some sources where you can purchase your own.
To make a mold of the face, you must first have a box of some kind to pour the rubber in. For this example, I'm using foam core board.I cut pieces to the dimensions shown. This will make a box large enough to fit around the shape. Glue the face down to the bottom with a few drops of super glue. Glue the box together and let it dry.To see how the face was sculpted, see the Sculpting Page.2.The kind of silicone I'm using for this mold is purchased from Micromark (www.micromark.com). It's called ONE-TO-ONE/RAPID mold making rubber. To use this material you measure out equal parts of A and B, which means you don't need a scale to weigh the parts.This rubber also has a 4 hour cure time, so you can start using your mold the same day you make it.Micromark 1-to-1 rapid mold making rubber is a very weak material. Although it is easy to mix, you won't get many castings from it before the mold will split. It is also not a good material for items with undercuts, as the undercuts can tear off pieces of rubber when you remove the casting from the mold.
Open the jars and use a paintbrush handle to stir each part well. Measure equal parts of A and B. You can do this easily by eye (I always seem to pour too much and the extra gets wasted).Pour both halves into one cup and stir it thoroughly. Be sure to scrape the sides of the cup while mixing.The 2 parts of this mixture are different colors. This helps you to know when the parts are mixed completely.4.Use a stiff bristled paint brush to paint a thin layer of the silicone rubber mixture on the face. Make sure it goes into all of the cracks and holes.This will ensure there are no air bubbles in the face of the mold. Rinse the brush out with paint thinner.5.Pour the remainder of the mixture on.Let the material set up f