ha forget the propane furnace go with induction, the savings in fuel and melt times will in a very short time pay for the investment.



I recently purchased a 15 KVA furnace, they do have one shortcoming when used for smelting precious metals but nothing that can not be operator corrected during the heat. It's all in learning about your equipment making necessary adjustments.

The bottom of the crucible lays below the heat zone preventing the flux to fully melt and homogenize with the charge and has to be stirred into the melt with a carbon rod. Melting copper and other metals works fine as the induction furnace actually stirs the molten metal down into the cool zone bringing the temperature up enough for a complete melt.

A misconception people think that an Induction furnace will only melt conductive metals, while it is true some metals melt faster than others for instance melting aluminium takes way more time to melt over copper or silver which melt quickly.

The aluminium being less conductive takes more time to melt, because metals are conductive we can use a cheaper clay type crucibles.

Now if we switch over to the graphite carbon type crucible which is also conductive the crucible itself becomes the heated element due to the transfer of heat from the graphite to the inside we can melt glass and other non conductive materials in this crucible.

Melting powdered metals we use the graphite crucible, the reason being that the metal powders have a very small surface area which do not react to induction heating.