Hot-Wire Cutting Test with ∅1.8mm Steel Wire 

Another Hot-Wire Cutting Test - This time with 1.8mm garden steel wire.
In contrast to the last test with the M3 threaded rod, the cutting quality was very good. The workpiece dimensions were right, the edges were smooth and the workpiece could be removed easily from the plastic sheet.
Using a smooth wire instead of a threaded rod solved another problem that I had before:
The wire is heated by high current from a modified microwave oven transformer and a variac for adjusting the voltage and with that current/heating power.
With the threaded rod, the conducting surfaces were the aluminum blocks and the thread from the threaded rod.
Because the M3 thread is so small the thread got heated glowing brightly until it burned away, which over time disconnected one side of the M3 thread from the circuit so that the M3 threaded rod got no longer heated up.
With the smooth wire, the contact surface is much larger and the problem no longer exists.
hackaday.io/pr...