Hot End repair holder

myminifactory

This holder makes working on your hot end more efficient. If your hot end is clogged for instance, you can remove it from your printer to make it accessible again. However, it's not very convenient to heat the hot end up with cables still attached to the printer. To make the hot end more accessible I created the "Hot End Repair Holder". Now you can remove your hot end from your printer and place it into the "Hot End Repair Holder". This holder also has the option of heating your hot end, so you can work on it at a high temperature. This will come in handy for unclogging or assembling your hot end. The temperature of the hot end is controlled by an Arduino Nano. You can connect the NTC of the hot end to it and set a maximum temperature in the Arduino sketch that's included in the files. See the picture of the screen where to set the maximum temperature in the sketch. If the Arduino is connected to a computer, you can see the measured temperature in the serial monitor. Also, the Arduino can take its power from USB. If everything is okay, you don't need the computer anymore and there's an option to give power to the Arduino from the 12V that powers the heater of the hot end. See the schematic, the red lines. The heater of the hot end is powered by a 12V ATX power supply of an old computer and a FET. This FET is triggered by an optocoupler, which is triggered by pin13 of the Arduino. See the schematic for more details. Next to the Arduino and electronic parts, you also need 2x M3x10mm and nuts. If you use the little bracket to hold the Arduino in place, you'll also need a small "wood-like" screw. The Arduino sketch is as follows: int ThermistorPin = 0; int Vo; float R1 = 10000; float logR2, R2, T, Tc, Tf; float c1 = 1.009249522e-03, c2 = 2.378405444e-04, c3 = 2.019202697e-07; int thresholdcold = 0; // Threshold for cold temperature int thresholdhot = 260; // Threshold for hot temperature void setup() { Serial.begin(9600); } void loop() { int heater=13; // hotend heater swich Vo = analogRead(ThermistorPin); R2 = R1 * (1023.0 / (float)Vo - 1.0); logR2 = log(R2); T = (1.0 / (c1 + c2*logR2 + c3*logR2*logR2*logR2)); Tc = T - 273.15; Tf = (Tc * 9.0)/ 5.0 + 32.0; pinMode(heater,OUTPUT); // declare pin 13 output Serial.print("Temperature: "); Serial.print(Tf); Serial.print(" F; "); Serial.print(Tc); Serial.println(" C"); if(Tc < thresholdcold) { digitalWrite(heater,HIGH); } else if(Tc > thresholdhot) { digitalWrite(heater,LOW); } delay(1000); }