A few are electric which has many advantages.
Build electric melting furnace.
Allow the furnace to heat the crucible and melt the metal before taking it out with tongs for casting.
After reading some of the comments and doing more research a simple controller to cycle the element on and off is recommended as the element is more likel.
None that i have seen are as easy to build as.
Kanthal is the largest supplier of electric heating elements but there are other suppliers like i 2 r elements duralite molycom and mhi.
This document describes how to build a furnace for melting metals like copper silver gold etc.
This is a homebuilt electric melting furnace.
Click on the image to go to the kanthal site where you can download specifications on kanthal wire and heating elements.
Most are based on cumbustion furnaces charcoal or propane.
A crucible is a metal container that you put inside of your furnace that holds the metal you re melting.
Once finished the steel bucket is cut away and a fire is built over the furnace to melt away the plastic inside.
I ve seen many projects out there for building a foundry for melting aluminum to make castings.
Similar techniques are used to produce the lid and the furnace is completed.
So after a few months the element did finally break although it was partly my fault.