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The brand new Mini Moulders Kopi kit from Squigy Solutions Ltd breaks the mould of replica modelling; or, more to the point, doesn't. That's the beauty of it.

Anyone who has never tried making a mould of a small treasured possession, to cast replicas of it, just doesn't know what a rewarding hobby they're missing; replicas can be cast in a whole range of different materials, including highly edible ones. Anyone who HAS tried making moulds will know what the one really big fly in the ointment so often is: BUBBLES.
To make a successful mould you need a material that starts out runny enough to encase the former to be copied, goes hard enough to keep the shape, flexible enough to remove the cast replica and tough enough to be used again and again. Silicone rubber is that substance. You buy It as a thick, white goo (almost as viscose as golden syrup) with a much smaller measure of catalyst (as wet as water but NOT nice to drink). Mix the two together and Hey Presto! Perfect mould material.

Actually, not always perfect. Imagine mixing a spoonful of water into half a glassful of golden syrup, very thoroughly. The mixture will have more bubbles in it than an 'Aero' bar with indigestion. Bubbles in the mix weaken the mould and? more often than not, lodge against the former which means the 'replica will always have little bubble shaped lumps on it.

Professional moulders solve the problem with industrial vibration tables and degassing chambers. Be assured, speaking from personal experience, homemade vibration tables (powered by a small hammer and lots of persistence) and degassing chambers (powered by a domestic vacuum cleaner) don't work. Nor does adding a 'Rennies' to the mix.

For the amateur mould maker the only practical solutions have been to make very thick walled moulds, with plenty of room for bubbles to rise away from the former; or two piece moulds which allow bubbles to rise directly off the former (half of any shape has less overhangs than a whole one). Neither type of mould is completely satisfactory to use, and both require a surprisingly generous amount of silicone; and silicone is expensive stuff.

Enter Mini Moulders. These little beauties are kits that come with a handy, lozenge shaped, capsule to make an economical mould in; and the answer to every moulder's prayer: A sachet with silicone base in one end and a catalyst in the other, with a 'poppable' seal in between. You mix the two together in the airtight sachet. No air, no bubbles. Problem solved.

Here's how you do it: First pick your former. Any small, solid object will do; as long as you DON'T use treated (or scented) wood, plasticine or clay. Otherwise, any object small enough
to fit into the capsule, without touching the sides. If it's strong enough to be pulled out of a rubber mould, NOT toxic, or hairy, it should be O.K.

When you've decided what to use you'll need to prepare the mould. All it takes is a bit of sticky tape over the outside of the hole in the end of the taller half of the capsule, after you've pulled it apart, and an adhesive lump ('Blu-tac' for instance) pressed over the inside of the same hole. Together these will stop the silicone from leaking and your former from floating. A quick smear of washing-up over the inside of both parts of the capsule and the job's done. Just press the bottom of your former onto the adhesive lump and put the capsule back together.

Now for the incredible bit. Take one of the two sachets in the kit and pop the seal between the two ends. To do this just lay the lollipop stick, also provided, across the white end of the sachet. Roll the sachet up, around the stick, like a tube of toothpaste. Do it slowly, and steadily, until the seal bursts and the contents of both ends can mix. Lay the sachet out again and scrape the edge of the stick over the white end to push all the contents into the green end. Mix the two parts together, still in the sachet, by rubbing it firmly between your fingers. After a couple of minutes the mix should be entirely streak free and ready to use. Push the mix to the other end of the sachet and give it another quick mix, just to be sure.

To get the mixture out fold one corner, of the empty end, over so that the end lays against the opposite edge and cut the resulting triangular corner off to leave a spout narrow enough to fit into the open top of the capsule. Squeeze the mixture into the capsule, slowly, until it is full. Leave it in a warm place for fifteen hours and you'll have a bubble free rubber mould.

To get the mould out of the capsule pull it apart again, remove the sticky tape and push it from below. A bit of careful wriggling will help. Gently peel the mould off the former and admire.

You can now use your mould to cast replicas in virtually all the usual casting materials except metals which are too hot, when melted, for silicone; candle wax is O.K. though. When you use the mould rub a little flour over the outside and put it back into the capsule, open end up (you don't need the sticky bits this time).

If you want to cast an edible material cut two zigzag lines down opposite sides of the mould, using scissors, to aid release. For safety's sake don't cast inedible materials In a mould before casting edible ones.

Finally a few useful tips: If your chosen former won't fit into the capsule find a container a bit bigger to use instead and then use both sachets. If you want cast materials that need to be melted, like wax, warm the mould first to allow bubbles in the casting material time to escape before it sets. 'Melt and set' materials can be re-melted and used again if you aren't happy with them; although you may find an alterative method of disposing of chocolate replicas. You should be able to use the mould over and over again, probably until you're fed up with that particular replica.

To find out what casting materials are available visit your local handicraft shop or look in the Fred Aldous Ltd catalogue.