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For this project I used:

  • a clay object to use as a master (see opposite for other types of objects you can use)
  • liquid latex
  • latex thickener
  • rubber gloves
  • tatty old brush
  • plastic tub
  • newspaper
  • talcolm powder
  • scissors
  • PVA/white glue (for repairs)

How to make a latex mould/mold

You can make a latex mould of any reasonably sized object that takes your fancy. I chose to make a mould of an ACEO (a miniature measuring 2.5 x 3.5 inches) of three sheep that I'd made from modelling material.

Allergies

Some people are allergic to latex, so please take the necessary precautions just in case. Use protective gloves and make sure the space is well-ventilated.

What to use as a master

Some materials work better than others, but most can be used:

  • Plaster of Paris is the best as it draws moisture from the latex causing it to thicken.

  • Clay is suitable but should be dried or kiln fired first.

  • Wood is apparently suitable, although I've never tested this one out.

  • Non-porous materials can be used, although metal can react with latex and weaken the mould. You will need to use the paint-on method or a coagulate(not used here) with this type of material.

  • Reusable putty/plasticene can be used but reduces the life of the mould.

mould step one
Methods

Dipping method: The instructions told me to "Use this method for materials that are porous." However, two things happened: one, the latex poured off the object and, two air bubbles formed in the latex. To get rid of the air bubbles it says in the instructions, "dip the object in again for a few seconds and with a brush burst the bubbles that form and spread the latex more evenly over the surface. Do this a few times until the latex turns to a paste which stops more bubbles appearing. Dip again and then leave for about 20 minutes, before removing and allowing any surplus to drip off. A mould which is thick enough should have formed "...in theory. In reality, the latex ran off the object more than it stayed on. I'm sure that other people can get this method to work, but if all else fails go on to Plan B, the paint-on method.

Paint-on method: I recommend that you use an old unloved brush for this as it does tend to cling to the bristles and resist all attempts to clean it off. The bristles shouldn't be too stiff either as it seems easier to paint the latex on with a softer brush. The best way of doing it was to paint a layer and allow it to part dry, before adding the other layer. "if the object is non-porous it will tend to run", say the instructions, "so only thin layers can be applied". Although my object was porous, the latex tended to run anyway.

mould step one
Using a latex thickener

If you get too disheartened about the latex being too runny, you can always turn to latex thickener. This is the last chance saloon of successful latex mould making. The assistant at my art shop gave this advice: "Latex thickener helps, but don't add too much or it will make the latex brittle". Returning from the shop with a lighter wallet and a small bottle of this magic ingredient, I did feel a little more optimistic.

mould step one mould step two mould step three mould step four

One: I added a small amount of the latex thickener before starting to coat the object. It does make the solution a little thicker, but it isn't noticeably different. However, I did manage to coat the object with a few layers.

Two: After a while though my patience was wearing thin. I cheated and decided to pour the latex over the object, which was placed on top of a plastic lid to contain the liquid. It didn't tell me to do this in the instructions, but I'd gone beyond caring what they said.

Three: Luckily, I'd put a layer of newspaper underneath the plastic lid and any leaks went onto that. I jabbed at any bubbles that appeared with my brush. Tip: The best way of cleaning your brush afterwards is to use warm water and a big blob of washing up liquid. You need to pull the latex off the bristles.

Four: I left the latex to dry overnight. To remove the mould, I sprinkled a little talcum powder over it to stop it sticking to itself and peeled it off. I trimmed off the excess around the edges with a pair of scissors. And tah-dah, I had a latex mould.

milliput complete miniature door

Five: The finished article doesn't look that impressive but is in fact incredibly detailed. It even picked up the marks I didn't want it to. Unfortunately I tore a hole in the latex while I was peeling it off, so did a quick repair job with some PVA/white glue and a spare bit of latex that I'd trimmed off the edges.

Verdict: The best types of masters are porous materials such as plaster or clay. Non-porous masters are a little trickier.

Pros: The mould is long-lasting and can be used several times. Latex can pick up fine details and is easy to remove from the object.

Cons: The latex is incredibly runny until it starts to set, making it tricky to coat certain objects. You can partially overcome this problem with latex thickener (see above) or coagulant (not used here).