ouch finger

include/config.h

@@ -42,19 +42,20 @@ static const float PID_KI = HEAT_PI_KI;
 static const float PID_KD = 0.0f;
 static const float GOOD_SPREAD_C = 5.0f;
 
-// Tiered heater cap during heat-up
-static const float HEATER_MAX_DUTY_COLD = 85.0f;
-static const float HEATER_MAX_DUTY_MID = 65.0f;
+// Tiered heater cap during heat-up (100% until near target)
+static const float HEATER_MAX_DUTY_COLD = 100.0f;
+static const float HEATER_MAX_DUTY_MID = 75.0f;
 static const float HEATER_MAX_DUTY_NEAR = 45.0f;
 static const float HEATER_COLD_BELOW_C = 10.0f;
 static const float HEATER_WARM_BELOW_C = 3.0f;
-static const float CORNER_LIMIT_BAND_C = 10.0f;
+// Corner taper only within this band below target (was 10°C — blocked heat-up in uneven chambers)
+static const float CORNER_LIMIT_BAND_C = 2.0f;
 static const float HEATER_SLEW_UP_PER_S = 18.0f;
 static const float MAX_TEMP_HEADROOM_C = 15.0f;
 
 static const uint16_t HEATER_CYCLE_MS = 3000;
 
-// Fan PWM — FAN_IDLE_PWM ≈ 30%; off only while chamber avg is below 40°C
+// Fan PWM — stir speed when target > 0; off below 40°C only when idle (target 0)
 static const uint8_t FAN_IDLE_PWM = 77;
 static const float IDLE_AUTO_FAN_OFF_TEMP_C = 40.0f;
 static const uint8_t FAN_MAX_PWM = 255;

include/fan_characterize.h

@@ -0,0 +1,75 @@
+#pragma once
+
+#include <Arduino.h>
+
+#include "config.h"
+
+class FanCharacterize {
+public:
+  enum class Phase : uint8_t { Idle, Precool, Heat, Hold, Cooldown, Done, Failed };
+
+  FanCharacterize();
+
+  Phase phase() const { return phase_; }
+
+  bool isActive() const;
+
+  uint32_t elapsedMs(uint32_t nowMs) const;
+
+  uint8_t profileIndex() const { return profileIndex_; }
+
+  uint8_t profileCount() const { return FANCHARS_COARSE_COUNT + 1; }
+
+  uint8_t currentFanPwm() const;
+
+  float heaterPct() const { return heaterPct_; }
+
+  uint8_t winnerFanPwm() const { return winnerFanPwm_; }
+
+  bool isRefineRun() const { return refineRun_ && profileIndex_ >= FANCHARS_COARSE_COUNT; }
+
+  const char *phaseName() const;
+
+  bool start(float maxCornerC, float avgTempC);
+
+  void abort();
+
+  void reset();
+
+  bool update(float avgTempC, float maxTempC, float spreadC, uint32_t nowMs, float &heaterDutyOut,
+              uint8_t &fanPwmOut);
+
+  void logIfDue(const float *sensorTemps, const bool *sensorValid, uint8_t sensorCount,
+                float avgTempC, float minTempC, float maxTempC, float spreadC, uint32_t nowMs);
+
+private:
+  struct ProfileResult {
+    uint8_t fanPwm;
+    float meanSpreadC;
+  };
+
+  void resetProfileStats();
+  void beginProfileHeat(uint32_t nowMs);
+  void enterHold(uint32_t nowMs);
+  void finishProfile(uint32_t nowMs);
+  void skipProfile(uint32_t nowMs, float maxTempC);
+  void planRefine(uint32_t nowMs);
+  void finishAll(uint32_t nowMs);
+  void fail(const __FlashStringHelper *reason);
+
+  Phase phase_;
+  float maxCornerC_;
+  float coolAvgC_;
+  float heaterPct_;
+  uint8_t profileIndex_;
+  uint8_t refineFanPwm_;
+  bool refineRun_;
+  uint32_t sessionStartMs_;
+  uint32_t phaseStartMs_;
+  uint32_t lastLogMs_;
+  float spreadSum_;
+  uint16_t spreadSamples_;
+  uint8_t resultCount_;
+  uint8_t winnerFanPwm_;
+  ProfileResult results_[FANCHARS_MAX_RESULTS];
+};

include/thermal_controller.h

@@ -456,7 +456,7 @@ private:
 
   void updateAutotune(float avgTempC, float maxTempC, uint32_t nowMs) {
     float duty = 0.0f;
-    uint8_t fan = AUTOTUNE_PREHEAT_FAN_PWM;
+    uint8_t fan = stirFanPwm_;
     autotuner_.update(avgTempC, maxTempC, cornerSpreadC_, nowMs, duty, fan);
 
     heaterDutyPercent_ = duty;
@@ -464,7 +464,7 @@ private:
     heaterOn_ = duty >= 50.0f;
     digitalWrite(HEATER_PIN, heaterOn_ ? HIGH : LOW);
     heaterBlock_ = duty > 0.0f ? HeaterBlock::None : HeaterBlock::Autotune;
-    writeFan(fan);
+    writeFan(fanManualActive_ ? fanManualPwm_ : stirFanPwm_);
     lastHeaterUpdateMs_ = nowMs;
     commitAutotuneIfDone();
   }
@@ -513,15 +513,7 @@ private:
     }
     heaterDutyPercent_ = applyHeaterRamp(duty, avgTempC, nowMs);
 
-    const uint8_t fanPwm = fanManualActive_ ? fanManualPwm_ : stirFanPwm_;
-    regulatingFanPwm_ = fanWithMinStir(avgTempC, fanPwm);
-  }
-
-  uint8_t fanWithMinStir(float avgTempC, uint8_t pwm) const {
-    if (avgTempC < IDLE_AUTO_FAN_OFF_TEMP_C) {
-      return 0;
-    }
-    return pwm;
+    regulatingFanPwm_ = fanManualActive_ ? fanManualPwm_ : stirFanPwm_;
   }
 
   static float clampPercent(float value) {
@@ -547,6 +539,11 @@ private:
 
   float allowanceFromMaxCorner(float maxTempC, float avgTempC) const {
     if (!shouldLimitMaxCorner(avgTempC)) {
+      // Heat-up: only taper when a hot corner nears the emergency ceiling
+      if (maxTempC >= EMERGENCY_MAX_TEMP_C - 3.0f) {
+        const float headroom = EMERGENCY_MAX_TEMP_C - maxTempC;
+        return clampPercent((headroom / 3.0f) * 100.0f);
+      }
       return 100.0f;
     }