1 KG Gold Digital Melting Machine Furnace Kiln 110V Refining Gold Silver 2102F
The furnace is small, easy to operate and will melt most non-ferrous metals such as lead, aluminium, brass, copper, bronze, gold and silver.
It is ideal for the casting hobbyist, or for the professional in applications such as manufacturing of small castings. It can be used for jewellery or for alloy research projects, or for heat treatment applications.
The furnace controls are easy to use and allows precise setting of the desired temperature. The furnace controls utilise a thermocouple which is used to reach and maintain a certain desired temperature.
The furnace comes with a standard 1Kg crucible, crucible tongs, anti-glare glasses and protective gloves. An adapter plate ring is used for the 1Kg crucibles, and is not used for the 2 or 3Kg crucibles. The tongs wrap around the top of the crucible ring and allows a safe method of removing a hot crucible, ready for pouring into a mould.
The lid lowers down on top of the furnace and must be in position properly to reduce any heat loss.
Spare crucibles are available for 1, 2 and 3Kg applications. The weight is based on the weight of gold, other metals, such as aluminium will weigh less for the same capacity.
How To Use It
1. Fit the supplied lid handle, found in the spares bag, to the lid. The other bits are for any ceramic spacers or insulators if replacement is needed. There is also a spare fuse.
2. Set the furnace on a stable flat surface such as a sturdy bench. Position the mould close to the furnace, so that the distance that you are carrying the hot crucible is minimal.
3. It is good practice to set a low temperature first, to allow the crucible to warm up slowly, such as 250*C. Let the furnace stay at that temperature for about five minutes. This also makes sure that the crucible and its contents are dry. Never use a moist crucible or add moist contents into the crucible.
4. It is also good practice to then set a medium temperature such as 650*C, let it settle, then set the final temperature such as 1140*C.
5. This implies that you are aware of the correct melting temperature of the metal that you are wanting to melt. The following table is to be used as a guide.
Metal / Alloy
Nominal and Range of Pouring temperature *C
700 - 740
1000 - 1180
1130 - 1180
1000 - 1090
1140 - 1180
360 - 415
255 - 310
6. Do not guess the temperature that you need to set. Make sure that it is correct for the type of metal and the considerations of the mould design.
7. Be aware that during the heating process, the indicted temperature will most likely overshoot before settling down to the correct temperature. This is not a problem as the real temperature of the crucible contents is actually lower, due to the lag in temperature of the crucible contents. It is good practice to set 2/3 a final temperature, wait for it to settle, then set the final target temperature. This will greatly reduce the indicted temperature overswing.
8. Do not add moist metal to a molten metal bath. The result will be at minimum, a major splash over, at worst, an explosion of the crucible contents.
9. When pouring molten metal into a mould, make sure that the mould has been pre-heated so that there is no possibility of moisture in the mould. It is good practice to heat the mould anyway as that will reduce the possibility of molten metal freezing in the mould before it has flowed to all parts of the mould. When pouring into a refractory mould, such as Plaster of Paris, make sure that the refractory mould has been oven dried.
10. Do not overfill the crucible. Fill only to about 2/3 capacity as you may spill molten metal during the crucible transfer to the mould.
11. Clean out the crucible after use, make sure that there is no stuck metal on the sides, gently use a scraper to clean metal out of the crucible. This is to prevent hot spots in the crucible and also to reduce contamination of the next melt.
12. It is vital that you accurately measure the wear of the crucible. Document what the inside and outside dimensions are, so that you can see how much wear has taken place. Use a digital ruler / micrometer to measure the wear. Do not go past more that 40% wear compared to the original new crucible dimensions. Most repairs of the furnace are caused by using the crucible past its useful life. This causes metal run-outs and / or flux boil overs.