HOW TO MAKE YOUR OWN MOLD WITH MOLDMAKER RTV SILICONE RUBBER

Mold making is so easy. Imagine making molds for your craft and casting loads of duplicates forever and ever.

You can make clay molds, soap molds, candle molds, epoxy resin molds, gem molds, figurines, miniature parts, and much much more. 

Here, we are going to walk you through how we made a mold out of Craftiviti Moldmaker RTV Silicone Rubber. 

We have this mold jewelry mold that was so used and torn (it broke a few months after this project by the way) and we wanted to duplicate this mold. 

In short, we decided to make a mold OF a mold. 

Here's what the old mold looks like. It's for casting clays and epoxy jewelry pieces. From the pic above you can see how deformed the mold is. We needed a NEW mold. 

First we made a border for the mold out of Monster Clay. We used Monster Clay because it contains no sulphur and is easy to work with AND it can be reused indefinitely. 

When making molds with RTV Silicone Rubber, never use any ingredients that contains sulphur. If you do, the rubber will not set.

Craftiviti Moldmaker RTV Silicon Rubber. Here's what the set looks like. 

It comes with 1kg Silicone Rubber and 50ml hardener.

Mixing Ratio: 3% hardener (that's the green stuff) to the weight of the silicone rubber. 

So if you have 100g of  Moldmaker RTV Silicone Rubber, you only need approximately 3g hardener. A dripper or pipette is the best measuring tool for this and a very sensitive weighing scale too. Once you get more familiar our Moldmaker RTV Silicone Rubber, you can roughly gauge 3g as 3ml. 

4% gets the rubber to set very fast. You can give 4% a try if you want a shorter working time. 

Give the mixture a good stir. Try not too incorporate too much bubbles into this mix. Stirring in a figure 8 always helps. Once the two colours are completely mixed, you will get a uniform pastel green liquid rubber mix. Work quickly as the rubber will start to cure. The open time is around 3 minutes. 

Slowly pour the mixture into the prepared mold. To avoid the poured silicone rubber from sticking to the original piece, spray a thin layer of silicone release on the surface of the original piece. 

Let the liquid rubber set for 1 hour.

Demolding time is the fun part. Just remove the Monster Clay border and slowly peel the silicone rubber away from the original piece. See how wonderful the  Moldmaker RTV Silicone Rubber duplicates the details?

Let's call this new piece a MASTER. 

Remember, these steps are for creating a mold from an original mold. However, if you just need to make a mold out of something you already have like a pendant or a carton figurine, simple use the item as your MASTER and pour silicone over it. 

Now we need to make a mold out of this MASTER. Place the MASTER into a box/container or you can build another clay wall around it. Here we used a simple food container just because the size was right. 

For bigger pieces or odd sizes, you can make a box out of acrylic sheets.

Next, repeat the same steps of mixing hardener with Moldmaker RTV Silicone Rubber. 

Slowly pour the liquid rubber over the master. Start at the edge and allow the liquid rubber to flow in a thin stream over your MASTER. Do this very slowly. This reduces bubbles from being trapped during the process. 

To help release more bubbles, just give the box a gentle tap.

Once the mold hardens (this took 3 hours) we just pulled the entire chunk out of the food container.

To get to the final mold, we needed to slice the rubber along the edges until we could see the joining of the two pieces. We used a normal blade for this. 

Once you see the joining, simply pry it apart. The Moldmaker RTV Silicone Rubber is extremely durable, as long as the rubber is thick enough, you do not have to worry about any tears 

Once the pieces have been separated, continue trimming the mold until you are happy with the size or shape of it. 

And here we have it. The original, the master and the MOLD. 

This new mold can be used many times over. That's the beauty of Moldmaker RTV Silicone Rubber from Craftiviti. It is ultra-durable and very flexible. Great for casting small parts, fine details and items with multiple dimensions. 

 It's that simple!

Email us if you have any enquiries at enquiry@craftiviti.com or pop by our store at 10 Boulevard and meet with us :)

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