I enjoy answering your question on my Youtube videos and have put together some of the most frequently asked so I can answer them in more detail with the aid of illustrations.
Feel free to ask anything that is not clear.
I can recommend Foundrywork for the Amateur and The Backyard Foundry, both by B. Terry Aspin. I bought these 2 books when I first became interested in casting and they gave me a good introduction to the craft. I also have The Complete Handbook of Sand Casting which is worth a read.
Can the sand be used again?
Yes. With the greensand I am using I let the sand cool and then pass it through my Super Sifter
A little water is sprayed on to get the moisture content back to a usable state.
Shown below are some snapshots from my Metal Casting at Home part 10 video.
|Here we see the split pattern. Note that on the ends of the pattern and at the top, some half round sections have been added. These are called CORE PRINTS and will not be part of the finished casting.|
When the two halves are placed together the half round sections form a full round section.
This is the core. The round section at the top and at each end will locate in the core prints in the sand mould. Because there are three it can only be positioned one way.
The core prints hold the the core in the centre of the mould.
|This is the sand core which will go inside the mould. Metal will not go where this is placed so it will make the casting hollow with the internal shape of the core.|
After the mould has been rammed up, the two halves of the flasks are parted and the
The impression left in the sand is the shape of the casting we want, plus the 3 core prints.
The core is located by the CORE PRINTS. Because there are 3 prints, the core is perfectly located and centred in the mould.
This is the casting removed from the sand after the pour. The sand core can be seen at the casting ends.
The core be easily broken out as it is only made of sand held together with a binder. Soaking in water helps soften the core.