How to make your own latex candle molds?The major asset of latex molds is their ability to produce candles in a huge variety of shapes and a great precision in the details. This is something a metal or polycarbonate mold just can't offer.
And what makes them really attractive is that they're easy to make yourself with very limited supplies, available in almost any Do-It-Yourself superstore!
What do you need?
How to make a latex mold?
1 Your first task is to find an item to cast and, very important, that is suitable to create a latex mold: unfortunately, not every item will do the job.
To give you an idea, the selected object must have a shape that is more or less "block-like". But if you don't intend to actually light up the candles you will cast in the mold you're about to make, then you're totally free in your choice.
Another point is that the object may not have any open part (for example, a character with the hands on his hips, because of the open space between the arms and the torso). Obviously, in such a case, it would prove impossible to separate the finished mold from the model. However, if there's only a very small open space, you can always fill it with some play dough or mold sealer
Try and avoid items that have been painted, unless they've also been varnished. I once tried to cast a latex mold from a small polyresin gargoyle; when it was time to remove the mold from the gargoyles, a large part of the stone-colored paint of the gargoyle stayed stuck against the latex: gargoyle beyond repair, mold ruined...
For this project, I choosed a Marsupilami-shaped salt shaker, ideal because the "body" of the salt shaker has the exact same shape of a small pillar candle. The resulting candle would burn quite well!
2 To cast the mold, a good option is liquid latex. You can find this kind of latex almost everywhere: in craft stores and in most Do-It-Yourself superstores.
Make sure that you work in a well ventilated room: liquid latex contains in average 40 to 50% ammonia (to help keep the latex in a liquid state in the bottle). And ammonia is not the most pleasant product to work with and is far from healthy to breathe. Always try, even in a well ventilated room, to keep mouth and nose below the level of your paintbrush and do not inhale the emanations (be assured, after 5 minutes with your nose above the bottle of latex, you will see Marsupilami's everywhere around you!)
Shake the bottle thoroughly before you start, otherwise the latex on top of the bottle (where you dip your paintbrush) will be way too liquid to be correctly and efficiently applied. Don't forget to close the bottle when you're done with a layer.
Every brand of latex is different, follow the instructions of the manufacturer: how to work with the latex, minimum number of layers and cleaning of the paintbrush can vary from brand to brand.
3 Place the object you want to cast on a sheet of waxed paper.
Apply the first layer uniformly on the entire model. You will notice that the latex holds better on some parts of the model than on others. In this example, I have had to insist a lot on the ears and nose of the Marsupilami because gravity made the latex flow downwards. Do not hesitate to add more latex on these delicate places and don't forget to regularly shake the bottle to make the latex thicker. But don't exaggerate: if you shake too hard, you will create air bubbles in the liquid latex. These bubbles may not end up on the mold!
It is important to create some kind of "lip" of at least 5 mm at the base of the model, or in other words on the waxed paper. This lip is necessary for 2 reasons: strengthen the opening of the mold, and allow the mold to be hanged on a cardboard plate (see the article about latex and rubber molds). The lip will also help unmold the finished candles. On picture 4, the bright white lip is clearly visible at the base of the model.
4 Depending on the brand of liquid latex you use, the drying time between each layer will be more or less long. Always wait at least one hour (two hours is better, some sources say four) for the last layer to dry before you start applying the next one.
"Fresh" latex is milky white and turns yellow as it dries. Always wait until every white spot disappears before you go on to the next layer. Some places where more latex concentrate, like the lip, need more time to dry than others.
Your mold will need between 10 and 15 layers (here again, some sources mention 20 layers) to be thick and strong enough to bear the heat of the paraffin you'll pour into it. Picture 4 shows the mold after the sixth layer of latex has been applied.
5 When the last layer has been applied and the latex is perfectly dry, remove the waxed paper (be careful not to shred the paper or you'll have a hard time removing every little bit of paper from the mold base).
Put a little dish washing liquid on your fingers and rub the whole surface of the mold: this will prevent it from sticking to itself when you will unmold the model.
As illustrated on picture 5, gently pull the lip upwards and remove the mold from the model like you would remove a glove (therefore, latex molds are commonly called "glove molds"): it will end up inside out.
6 Your latex mold is finished and ready to use.
Do not think it will last forever: you should be able to cast an average of fifteen candles with one same mold before it starts to break up... then you'll have the pleasure to make a brand new one :)
NEVER add stearine to the paraffin for use in a latex mold. Don't forget that stearine is an acid and that it would eat up the latex without mercy.
To further extend the life of your latex molds, store it in a dark place and, before you unmold a candle, always coat the mold with a some dish washing liquid.