Sorry - noob question follows: What all would one consider to be the “calibration” of a 3D printer? For instance, what would it mean to you having been told an assembled printer shipped fully calibrated? Some of us new to FFF 3D printers might only consider the print bed/nozzle relationship to be what the calibration envelope consists of, and yet, I intuitively believe there is far more to it then that. Enlighten me, please.
Don’t apologize for asking a question. We’re a noob-friendly group! 
If I was told that an assembled printer was "calibrated’ I would expect two things:
-
The physical structure has been adjusted to the best ability of the assembler such that it is level and works without additional changes to the physical structure.
-
Settings stored in firmware have been set to provide the expected output (steps/mm for instance on the steppers)
The latter is reasonable IMO, but the former really isn’t. Shipping causes things to move and settle. I’m coming at this from years ago when I started out and it may be that companies and people are much better than they used to be, but I don’t feel like there are any ‘plug and play’ printers yet - at least not in the sub-$30k space. All printers are going to require some attention and messing around.
Thanks. I know that this is the type of question often asked and answered, but not as easily rediscovered a month or two afterwards. Although, I had been following this community for a few months now, I had only seen partial answers to this subject, all piecemeal. I’m hoping for a list of things included in a calibration, mostly for machines under $2K (US).
Square it, adjust the enstops, tram the platform. Then maybe adjust the stepper current and PID settings. If you have a dual extruder, you’ll have to make sure the nozzles are even and measure the offset. Everything else is math. Any assembled printer or kit that requires more than this is to be avoided (self-sourced or custom jobs are a little different).
Of course, you’ll also need to measure the diameter of your filament and figure out the correct temperatures, but I don’t consider that part of printer calibration.
@Whosa whatsis - thank you sir for a straight up answer. I believe I understand each of those except the PID settings. BTW: My February Bukito will be a kit, but my assembled RigidBot BIG will be “fully calibrated.” And this question has been danced around in several communities and I just want to be prepared.
PID (Proportional Integral Derivative) refers to the temperature control settings. PID systems are closed loop controllers that try to minimize the error between the set point value and the actual value. PID is an on/off system that can adjust how long a heater stays on to avoid over shooting due to the system’s hysteresis. Whereas a regular on/off, or bang bang, can only turn on when the temperature is under what you set it at and can only turn off once it reaches that temperature. Which will always result in large temperature fluctuations unless the system’s hysteresis is very small. The PID settings affect the behavior of the system and are related to the hysteresis. If the PID settings are not correct, then you may be reading the wrong temperatures (wrong thermistor table), or have terrible temperature over/under shooting. A properly tuned PID will hover very near the set point value.
If it’s fully assembled and calibrated (“ready to print”) then I’d expect all the software settings too - eg Slicer settings, temp settings for PLA and ABS filaments, bed positioning etc.
Um, thermistor table selection is separate from PID settings. You can have the right PID settings to stabilize temperature, but it will read the wrong temperature (and thus stabilize at the wrong temperature) if your thermistor table is wrong (@Ben_Malcheski , I think you understand this, but I’m clarifying because what you wrote was easy to misinterpret). This one of the differences I mentioned when dealing with a self-sourced machine vs a kit or pre-assembled machine.
@Clint_O_Connor Filament settings will be different for each supplier, and it’s always advisable to check the endstops and bed tramming (and squareness if you’re making parts for which this is vital) after transporting a machine, especially shipping it.