H2D Automatic Poop Chute Door

If you're looking for an excessively over-engineered solution to a problem that probably doesn't exist, you have come to the right place!

I was looking for a way to cover the big hole in the back of the printer while heating the chamber. I came across a pretty cool model that was an automated version of another model which started as a manual door. 

Well, I decided to over engineer it even further. The previous version had a temperature sensor.  When the temperature went up, (chamber heating), it closed and opened again when it got cool. While this is probably fine, I wanted more control. 

The controller now connects to your WiFi and it can be controlled via a web utility I included, or through an automation platform like Home Assistant. I have my printers connected to Home Assistant and they share a great deal of information. Now I can manually open and close the door from the Home Assistant interface, and Ive created some automations that take care of that for me. It closes when the printer heats the chamber, opens temporarily when the printer changes filaments, (to let the poops out), then closes again. Finally, it opens again at the end of the print. When a print does not require a heated chamber, It does nothing. (stays open). 

I modified the model to remove the temp sensor and close the holes for its wiring. I also changed the hole size for the magnets. I printed in ASA and there was quite a bit of shrink, so i had to oversize the holes to get the 6X3 magnets to fit. 

This is an advanced project and requires some knowledge of Home Assistant and Arduino. I wrote up pretty detailed assembly instructions and included all the code for both the microcontroller and the YAML code for Home Assistant, but you still have to know what you're doing, and feel comfortable around a soldering iron. 

For the poop slide that works with this, use this model and look for the modified print profile by lauretiu. That slide has been cut down to accommodate for the gate. 

https://makerworld.com/en/models/1265042-h2d-poop-chute#profileId-1645147

Here are the parts I used. 

Servo

https://www.amazon.com/gp/product/B0D5Y5VK7D/ref=ox_sc_saved_image_1?smid=AT4GDZOF91C2O&psc=1

Controller

https://www.amazon.com/dp/B07WC2KZS9?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1

OLED

https://www.amazon.com/MakerFocus-Display-SSD1306-3-3V-5V-Arduino/dp/B079BN2J8V/ref=sr_1_5?crid=386656D1VLTWL&dib=eyJ2IjoiMSJ9.WfbjWEtNeyNZv60BO3Eh_MkMsgLfkblQ3zSlZHL-zLrD1ontSNhgmMoYo_Hjm6oSzXYondzd6wtIFm3tDr5Ep6xJ2EE2IYcATYOQkqk6cPQLOSSXAf1TuL7IyPnczUnHzyVGkqBNULMZWfc-qp-AJdCKeyD4btHufZ2R7yvVFCEprn1LMrGzKCLHn0JvEsxbwYd4-2ZTe8_Ke2IMb9OEbfNWeckmI51sAGGFeummrXPoodIpBmY-VGCMUMicm6HPbWekIGzsKJdtpazysHF0371xNGsAwrxCK49Pldk9k5I.2-PV3byki3lhmiSVEPFpCiKqxGLaQ6KLMGLxhnp-Lwk&dib_tag=se&keywords=i2c%2Boled&qid=1755324015&s=electronics&sprefix=i2c%2Boled%2Celectronics%2C210&sr=1-5&th=1

A couple of notes:

1. When you secure the gear to the servo, I found that if I left it a little lose, it would mesh better if it was allowed to wobble. So far it hasn't had any issues like that. 
2. If your servo it ticking or twitching, make sure the data wire, (orange) is routed away from the center of the arduino board. The board outputs a lot of wireless transmission, and I chased ghosts for a while trying to solve a problem that existed simply because the wire was picking up interference from the board. 

I hope you enjoy.