Tungsten Carbide MK8 Nozzle

Something is off with this nozzle. It clogs pretty much no matter what filament I use. Normal PLA I had to increase nozzle temp 20C AND change nozzle size to .3mm in order to get a print without clogging. Carbon fiber PETG? Not happening. I have to run it ridiculously hot to get it to even extrude and then it still clogs. There is no way this nozzle is .4mm For what I paid for this I'm extremely disappointed.

I've own a ruby, and I've destroyed a ruby (crashed my bed into it). This is a one piece nozzle that retains good temps and can deal with abrasive fibres. I purchased the 0.6mm and its good. I can still print at 0.12 layer heights, or I can print at 0.48 layer heights... Perfect.

I'm very disappointed in the 0.4 mm version of this nozzle. I switched out a standard brass nozzle on my Ender 3 in order to print with abrasive filament, expecting it to be an easy swap. But I had immediate and severe under-extrusion problems even with regular PLA. These problems could only be partly remedied by a combination of both dramatically increased temperature (+30°C) and low speeds (<40 mm/sec). I thought that maybe there was something amiss with my hotend after the nozzle switch, so I used this as an excuse to buy a Microswiss all metal hotend, that I installed first with this nozzle. I had the exact same under-extrusion problems. Switching in the coated brass nozzle that came with the Microswiss kit instantly solved all my problems, and I was back to printing at full speed using reasonable temperatures immediately. Perhaps I got a dud. Perhaps I'm doing something wrong. Either way, this nozzle has been a big waste of time, money and filament. If I had the chance for a do-over, I would just buy a hardened steel nozzle and live with the well-known temperature differences.