Step 14.2 — Confirm the heaters are already PID-tuned¶
Step 2 of 36 · Chapter 14 — Calibration and tuning
(no image — see text)
Parts: none.
Do: Both heaters were tuned and saved in Ch 13 at Step 13.29; do not repeat that here. Open printer.cfg and confirm both PID stanzas are in the auto-generated block at the bottom.
Check
Both stanzas hold your numbers, not the LDO config's generic starting values.
What you're looking at
PID constants are the three numbers that hold a heater steady at a target. They were measured in Ch 13, and they belong to the temperature they were measured at, so changing your bed target means re-running the tune.
Ch 13 owns the tuning procedure
bed at 100 °C, hotend at 245 °C with the part fan at 25 %. Re-run it only if you have moved a target since, for example re-tuning the bed at TARGET=110 for ASA; PID is most accurate near the temperature it was tuned at.
Caution
Do not re-run the hotend tune at the 260 °C print temperature. PID_CALIBRATE switches the heater off only at the target, and [extruder] max_temp is 270, so a 60 W Revo HF can overshoot and shut Klipper down mid-tune (verify on bench). To tune at the print temperature, raise max_temp to 290 first, under the core's rated 300 °C, then set it back.
Tip
the generic values are 58.437 / 2.347 / 363.769 for the bed and 26.213 / 1.304 / 131.721 for the hotend. Do not add pwm_cycle_time; Klipper's 0.100 s default is correct here.
Source: Voron startup wizard § PID tune bed & hotend · leviathan-printer-rev-d-sbv2.cfg · E3D Revo 60 W heatercore / 104NT thermistor