This post is designed to offer help to K1 Max users who want to upgrade their K1 Max + CFS printers to reliably print ABS, ASA and Nylon etc. I have been using my K1 Max for 2 years with pretty reliable, but not perfect, results on PLA and PETG. However the machine is now excellent for printing in ABS, ASA and Nylon but it has taken research and some work.
Over the 2 years I have added a CFS kit and a rear poop chute for multicolour printing, and a Creality chamber heater for printing industrial filaments. But by far the best upgrade was the addition of a Ram3n graphite bed in place of the wobbly taco bed. This upgrade has transformed the printer from good to excellent, with a near perfect first layer every time over the whole bed.
However, whilst installation of the graphite bed was not difficult but takes care, to get the best from it is necessary to change the bed thermistor specification and carry out a bed temp PID. This requires the printer to be rooted.
Now everything I read online makes it clear that rooting the printer if using the .33 firmware is challenging because the Guilouz Helper Script does not work out of the box for machines running .33 firmware. It seems that the Helper Scripts are designed for printers running .27 and .34 firmware. But I do not have a copy of the .27 firmware, and I do not like the .34 because it is unsuitable for printing high temperature filaments because of cooling the bed to 50 Deg C before wiping the nozzle.
So, I rooted my printer using Scratch 3D Printing advice from here: https://www.youtube.com/watch?v=tildH_i2gGY&t=767s but like him I only included the files absolutely necessary to gain access to the printer Config file via Fluid. I did this because I understand that things like KAMP will upset a K printer with CFS. However after following Scratch 3D, I could not get access to my printer via Fluid, but this was fixed eventually simply by clearing the cache and data from my web browser. Once I had access to the config file, I could change the thermistor spec as advised by Ram3n and undertake a bed PID.
I hope this helps others to upgrade their K1 Max + CFS to enable it to become the workhorse it deserves to be.