The casting process has been an extremely long and drawn out one. There has been a period of problem solving to get results that are close to what i would be happy with and even then the process is still so full of variables that it is very difficult to be consistent.
1. The first big issue that I encountered was that the furnace was actually too small for the size of crucible I would need to melt enough aluminium to cast each leg.
the first thing that i did to get over this was to lean three brick against the edges of the furnace and carefully balance the lid on top of that. This seemed to work and I managed to create my first cast leg. The first leg did not come out well because I made the mistake of having the mould sitting at an angle. I thought that this would improve the flow of the aluminium which it did but it meant that-the material thickness was uneven and in the end made the casting unusable.
The next time i came to use the furnace I was unable to get it up to temperature which was extremely frustrating as it takes a huge amount of time and preparation for each pour i decided that the reason for this was down to the lack of insulation leading up to the lid and that I would need to make an extension on the perimeter of the furnace to allow me to sit the crucible in comfortably.
The solution that I found was to buy some terracotta tiles from the local hardware store and cut them into strips and then offset stack the brick around the edge of the furnace to give it height. This seemed to work well.
Over the next few pours I learnt more things which would go onto improve the Process.
1. Always clean out the furnace before each use.
Leaving the debris even if its still hot and feels like a good idea is actually a bad idea. It clogs up the air flow and in the end wastes fuel.
2. In the future do not use coal as a heat source.
The main cause of most of my issues has been the fact i have been dealing with so many variables one of the most infrequent is the use of charcoal this could have been completly avoided if i had used a Gas heat source.
3.Pour over the details first.
For the lettering to come out well it must be poured first as this is when the aluminium is hottest meaning it is most likely to flow well.
4. I need to use the maximum aluminium that the crucible can hold any less and I will not be able to get a full casting.
It would all be much easier if both the furnace and the crucible were larger as it would leave a larger margin for error in the pouring proccess
5. Use a double mould if possible
Trying to to use an open mould has meant that the casting are in accurate and it is very difficult to fill the mould as i have to physically move the crucible around the shape which is not ideal. If i were to do it again i would like to make a proper double mould.
