I had to resort to using the high temp extruder that came with the Qidi X-CF pro because I print ASA and the normal extruder is not suitable for nozzle temps in the 250-260 degree region.....the teflon tube fails.

The high temp extruder takes hardened MK10 nozzles with 2mm filament bore. I read somewhere that hardened steel nozzles are not very good for more normal filaments and tend to clog because of friction in the nozzle. This was happening to me.

Brass MK10 nozzles with just a 2mm filament bore are not available, only 4mm bore.

My solution has been to convert the normal extruder to an all metal heatbreak and use the normal MK8 brass nozzle that comes with the extruder.

Done about 10 hours of printing now without any problem Using the same reel of ASA filament that was unusable with the hardened steel nozzle.