I just wanted to mention a small inaccuracy in the video regarding thermocouples. You said that the thermocouple (Type K) couldn't go any higher than 250 deg.C.
This is incorrect, all Type K thermocouples are accurate up to 1350 deg.C and down to -200 deg.C (per definition/standard they are all made from the same alloy), and all good thermocouple meters should also be accurate in that range.
However the plastic insulation on the wires are probably only rated for 250-300 deg.C. But this does not matter in your case since you are only heating the tip in your experiment, and even if you would char the insulation close to the tip, it would not affect the measurement.
Type K alloy:
Positive: Chromel (90% nickel, 10 % chromium), non-magnetic, melting-point 1420 deg.C
Negative: Alumel (95% nickel, 2% aluminum, 2% manganese, and 1% silicon), magnetic, melting-point 1399 deg.C