Homemade Hot Plate for Wireless SMD Soldering! Using ESP32, Flat Iron, and IR temperature sensor

I need to solder many PCBs, so I decided to build a Reflow hot plate for SMD soldering. My idea is to use it as an everyday tool, so I decided to improve all the available designs online.
This hot plate is able to measure the PCBs temperature using an infrared temperature sensor rather than a temperature sensor attached to the plate, it is able to follow any soldering temperature profile storage on a SD card and, thanks to a ESP32 microcontroller we can also upload wirelessly any temperature curve we want to follow as well as start the cycle wirelessly. In summary, we can upload and run any reflow curve we need. Imagine all possible use cases!

Code, library, and sketches:

https://drive.google.com/drive/folders/1MhhFXRYQWRVhH6q7kccW19OZH8Fg5vI1?usp=sharing
https://www.instructables.com/The-Ultimate-DIY-Hot-Plate-Powered-by-ESP32-and-IR/

Useful links:

- EPS32 board: https://www.amazon.es/diymore-unids-ESP32-Desarrollo-Bluetooth/dp/B09Z6RLS7R/ref=sr_1_2_sspa?__mk_es_ES=%C3%85M%C3%85%C5%BD%C3%95%C3%91&keywords=esp32&qid=1661200780&sr=8-2-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFHWFBNME9aWTRWR0kmZW5jcnlwdGVkSWQ9QTAxNzI3NDBLU1E5TVNaMU03M0cmZW5jcnlwdGVkQWRJZD1BMTA0MzczMUU2SkxBUUhUWUNKMyZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU%3D
- SSR: https://www.amazon.es/gp/product/B08FWWRK2Y/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1
- IR temp. sensor: https://www.amazon.es/gp/product/B07YKNQQ7P/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1
- LEDs: https://www.amazon.es/gp/product/B0B7NHNKVH/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1
- Power regulator: https://www.amazon.es/gp/product/B08R2LB2CZ/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1
- Soldering paste: https://www.amazon.es/gp/product/B07BZF3M5W/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1
- ESP32, SD and WiFi: https://www.youtube.com/watch?v=zoYMU1tA3nI
- See also maker.moekoe project: https://youtu.be/39ij7f1OWtc
- See also ELECTRONOOBS project: https://www.youtube.com/watch?v=C7blZigaaaA

Chapters:

00:00 Introduction
00:48 Components
01:53 Preparing the iron and the box
04:36 Electronics
05:48 Algorithm
07:14 Testing the performance
09:07 Soldering a PCB