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To start with a pattern is required of the object that you want to make.

This is often made of wood and made be made up of several parts depending on the shape of the object. It must be remembered that the pattern must be removable without destroying the mould that you have just made. The pattern also needs to be tapered to assist in removal and slightly larger than you want the finished object as the metal will contract as it cools.

If you want to cast a pyramid, this is easy as it has a flat base and tapers in so can be a one part mould. A cube again has a flat base but the straight sides will need as slight taper to assist in removing the pattern but can be a one piece mould. A sphere on the other hand will have to be a two piece mould, cut the sphere in half and the mould will have half in the cope and half in the drag of the casting box.

As you get more advanced you can start making sand cores which means that you can cast objects with holes in them.

 

Start by laying out your patterns in the inverted bottom half of the box, make sure there is enough space between each pattern so there is no collapse when the pattern is removed but they are close enough toopen up passages for the metal to flow through all moulds without any dead ends.

The patterns have been "dusted" with release powder to aid the removal of the patterns.

 

The casting sand can now be put in and rammed carefully but firmly round the patterns. keep adding sand and ramming down until the box is full. The sand can then be struck off level and the box turned over and the top half attached.

The patterns and lower box can again be dusted to aid with the seperation, the pourer and riser can now be added and the sand packed in to fill the box.

The two halves can be seperated, the pourer, riser and patterns can be removed the flow channels can be cut and the box can be put together again. The mould is now ready for pouring.