Understandably, this is a skill that most people shy away from. It’s a real shame, too. They use this skill in the props industry as it’s a great way to get many pieces out relatively simply. Having attended a panel on mould making, I now want to delve deeper into the world of mould making and understand how it all works. Over the coming weeks, I hope to be able to get all of the required equipment and tools to make good moulds and start casting.
But first, it helps to understand what mould making is exactly and why people do it. In ye olden days (heck, even today), a blacksmith would create a mould which they would cast their molten metal into. This is the process of casting. So you have two parts to this: Moulds and Casts. Simple enough to understand.
Equipment – What do I need?
You will need at least the following for your moulds and :
- Sharp knife
- Disposable pots (see through plastic cups are the best for this)
- Disposable sticks (for stirring)
- Old clothes (… You may get some on you).
- Hot Glue Gun (And hot glue stick…)
- Your mould materials (more on that later)
- Disposable pan (or area to make the mould)
I learned some cool things from the panel. If you want to break something from hot glue, apply 99% proof alcohol to the hot glue. It dissolves the glue, allowing you to easily peel off whatever you stuck down with alcohol. Useful tip! Also, if you don’t have a disposable pan for making a mould, why not use foam board (also known as foam core)? Cut it to size, stick it down with hot glue and wham – You have a container for your mould!
Buying a respirator
There’s a bit more to buying a respirator than first meets the eye, it seems. A respirator is simply something you put over your nose and mouth to prevent yourself breathing in fumes, dust, chemicals etc. When you work with resins, you will want to make sure you work in a well ventilated area and you use proper protective gear. This comes later, but it’s important to note that if you work with fibreglass (common in the UK), you will need a respirator and goggles, along with other protective gear. This is because you will be breathing in glass without a respirator… and from what the panel taught us, that means you will be coughing up blood. Be careful and be safe.
You will want to get a respirator with replaceable filters. I’ve gone for a 3M 7500, which cost me about £25 with filters. You can get it cheaper, but just be careful with what you get. Read the instructions on what your filters are for, as well as read the instructions on how to use the respirator. Your eye protection/goggles shouldn’t necessarily cost any more than £10.
Make a mould
This is surprisingly easy. It’s a case of getting the materials from a website such as MBFG.
To start off, you’ll need to buy some silicone. There are other materials to use when making moulds, but silicone seems to be really simple to use and can make quite a few moulds in the long run. Here’s an example of mould silicone that you may want to consider when making a mould.
You’ll need an area, a container of some kind, to keep the silicone in. Once you’ve gotten that, pour in your silicone over an object you’re going to be making a mould of. Perhaps you’ll want to make a mould of an existing object, such as a model. If you use the foam board tip from above, you can make a foam container relatively inexpensively and cut it to size. Stick it together with hot glue, stick your model to the base of the foam container and pour in your silicone. The above video is a good example of someone creating a mould and casting an object, so you can see just how it’s done.
Once I’ve made my first mould, I’ll write a post about it. We’re hoping to launch a GeekOut Newsletter fairly soon, so perhaps we’ll include it as a unique post for the newsletter for those of you who are interested in what happens around our GeekOut activities.
That’s it for this issue, hopefully it’s at least a little be interesting. Have you ever made a mould before? Have you ever cast an object before? Let us know in the comments below, over on Facebook or Twitter.