Experiment with "First Order Plus Delay Time" (FOPDT) temperature tracking

[ReXT3D]

I finally posted a “walk through” for one possible approach to manual PID tuning:

Manual heater PID constant derivation by example

Background Many people (myself included in my early 3D printing days) implicitly expect off-the-shelf near “perfection” of the heater performance of their printer. It takes time and practice to learn and appreciate that PID controller tuning is a largely empirical process without a one size fits all solution. Different printer firmware uses different implementations of the PID controllers and different methodologies to derive (approximate) the process PID constants. When this is combined wit…

Please feel free to critique or correct any errors or omissions. Hopefully it will help some people, particularly in some of the corner cases that seem to exist where bed temperatures do not converge (although some of these cases may have other systemic causes).