Heatblock Thermal Images 2 - Toolhead

To compare with the previous thermal images, I captured another series of pictures of the heatblock, this time at both the minimum and maximum fan speeds achievable by my 9290. The images were again taken at ~255°C with the chamber at ambient temperature. The first set shows minimum speed, the second is at maximum speed.

With minimum speed, the 80 W heater operated at ~30% PWM. At maximum speed, it rose to ~90% PWM, since the silicone sock had to be removed to view the heatblock directly. Without insulation, the heatblock is heavily cooled by the circulating air, forcing the heater to work harder and creating even stronger temperature gradients. With insulation, peak temperature won’t climb as high, but these results highlight the limitations of a steel hotend.

As expected, the titanium shield is cooled by the airflow and stabilizes at under 150°C making it a safe candidate for additional insulation such as Kapton tape or a thin layer of RTV silicone.

These measurements confirm how sensitive the heatblock is to airflow and insulation. The next step will be to test extra insulation on the shield to determine whether it can reduce nozzle cooling issues and improve thermal consistency across the hotend.