This is a quick first test in open air on DC power supply power to see how the hotend cooling fan and heatsink work on the new all refractory electroceramic hotend, for printing metals and ceramics, we have constructed out of a ceramic glow plug for the ender 3. <br /><br />The ceramic glow plug described on my printables here:<br /><a href="https://www.printables.com/model/635347-beru-glow-plug-cgp-002" target="_blank" rel="nofollow">https://www.printables.com/model/635347-beru-glow-plug-cgp-002</a><br /><br />was EDM drilled with the stock powercore at 7mm/minute plunge rate constant no pecking. 140 RPM spindle speed. 0.5mm OD, 0.3mm ID brass electrode. 3000PSI of flushing pressure 72 volts on the pulse generator at 2Khz pulse frequency, stock powercore and stock settings. Time to drill : about 30 minutes. electrode started at 400 mm long, ended at 150 mm long. <br /><br />Rack Robotics and their Powercores can be found here:<br /><a href="https://www.rackrobo.io/" target="_blank" rel="nofollow">https://www.rackrobo.io/</a><br /><br />actually printing with this hotend should be coming soon...<br />...<br /><a href="https://www.youtube.com/watch?v=WJhoQCzLPT4" target="_blank" rel="nofollow">https://www.youtube.com/watch?v=WJhoQCzLPT4</a>