Hi i've come across a problem at work and was hoping someone could help me to understand what is going on exactly. power supply: 6kW, 9.2A, 5890V, and running at approx 50kHz. this power is routed through ∅3mm Kanthal AF bar, threaded at one end, and what we see is resistive heating through the bar, but almost twice as hot at the thread as anywhere else. my first thought was skin effect, so i tried reducing the diameter of the bar but it was (almost) the same temperature at ∅2.4mm. My question is can anyone explain why the threaded section causes so much more heat?