Making a mould from Liquid Latex is a relatively simple process as a result of its easy to use nature and versatility. It is also an extremely cost-effective way to produce a mould, not only in terms of material costs but also in relation to the long-lasting properties of this material.
Whilst cost benefits and durability are two of the key benefits of this process, one of the drawbacks is the length of working time. It can be a lengthy process as Latex moulds are built through multiple layer application.
With the right preparation and application tips, you can easily make many duplicates of your chosen item.
What you will need;
A common question asked by our customers at FibreGlassDirect is ‘What object can I make a mould from using Liquid Latex?’ Liquid Latex can be used to mould almost anything with the exception of skin. Applying directly to a person’s skin will cause damage and seal the skin from the air.
Some common Liquid Latex moulding projects include;
By thoroughly cleaning your chosen item, this will ensure you end up with no nasty surprises when you lift the latex at the end of the process nor will it interfere with the curing process.
Soap and water generally are enough to lift any dirt, dust and other contaminants from your mould. Ensure the item is thoroughly dry before starting to apply the latex.
It is best practice to apply the latex to the item whilst it is on a completely flat and smooth surface. This will allow you to create an outer flange beyond the edge of your mould. This is helpful when casting inside the mould down the line.
If your object does not have a naturally flat side, a piece of modelling clay can be placed underneath the object to provide a flat surface and give you the ability to create a flange.
Most moulds will take between 6 and 30 layers. A Latex thickener (from the second layer onwards) is recommended to reduce the number of layers needed. It is also extremely beneficial for heavy or vertical layering when a bulkier application is required.
The Latex may be applied by dipping the mould into the Latex or by brushing it on in thin layers. Allowing gentle air pressure to the mould will help the Latex to work its way into intricate and detailed parts of the mould.
When applying the Latex with a brush, we would recommend brushing a couple of centimetres beyond the edge of the mould. This creates a flange as stated previously. It is important to take particular caution with the first layer as this will be the surface of the mould. Ensure there are no air bubbles trapped in the Latex. The next layer can be applied as soon as the first layer is dry. When dry, the Latex will turn amber from its original milky appearance.
There is no curing time as such with the Liquid Latex supplied by FibreGlassDirect as the product is already vulcanised. Drying time will purely depend on film thickness and temperature. You may force dry if required but at temperatures no higher than 80 degrees Celsius.
The more layers of Latex that are applied, the stronger the mould will be. The number of layers will depend on the size of the mould. Smaller moulds will require less.
For larger moulds, you may wish to add a layer of reinforcement such as gauze or glass woven fabric for strength and stability. This will help to stop the mould from going out of shape when filled. Care should be taken to avoid reinforcing areas that will need to stretch to help release the item from the mould when filled. Moulds will often become deformed towards the bottom/end of the mould as it has the most weight to support.
Once enough layers have been applied, allow the mould to completely cure overnight.
Once the Liquid Latex has completely cured, you will be unable to apply further layers as it will no longer bond with the surface.
The cured Latex should peel away with ease from the surface of the mould, inside-out. If there are some intricate parts to the mould, take great care releasing these sections. You may gently stretch the Latex if needed to avoid tears or damage to your original object.
Once completely released, your mould is ready to be filled with Plaster of Paris. Ensure you build a stand which will support the mould once filled. A common method is a wooden box filled with sand which helps to reinforce the mould.
If you need further information on Moulding from Liquid Latex or moulding in general, contact our team. FibreGlassDirect has over 60 years’ experience in fibreglass. Our knowledgeable team are on hand to answer your queries.