I recently built my own solder reflow oven, inspired by a project from DigiKey’s YouTube channel. While I followed the general concept, I made several upgrades and changes to optimize the performance, improve usability, and enhance safety. Here’s a breakdown of the modifications and improvements I implemented.
Upgrades and Customizations:
1. Capacitive Touchscreen: I replaced the original resistive touch display with a modern capacitive touchscreen, which offers a smoother, more responsive interface at a lower cost.
2. Improved Thermal Management: I added a heat sink to the solid-state relay (SSR) to better manage heat dissipation, increasing reliability. While heat sinks weren’t used in the original build, I found it necessary for safe operation.
3. Solid-State Relay Choice: I opted for a more affordable SSR that still met performance requirements. However, I made sure to invest in quality to avoid potential overheating and safety issues.
4. Thermocouple Amp Selection: The original amp had complex features like open circuit detection, which could cause issues during operation. I switched to a simpler, more reliable MCP9600 amp that just measures temperature without extra error-checking functions.
5. Power Supply Modification: I integrated an AC-DC converter for self-powering, eliminating the need for USB connections and reducing ripple noise by adding a linear regulator.
6. Microcontroller Upgrade: To enhance the UI responsiveness, I replaced the Arduino with a more powerful ESP32, significantly speeding up the display refresh rate.
7. Safety Features: I kept the oven’s built-in thermal switch and timer as backup safety measures. These features provide redundancy in case of overheating or other issues.
8. Toaster Oven Adaptation: I modified a budget toaster oven, bypassing the built-in thermal switch to avoid unreliable temperature cycling while maintaining some safety functionality.
For those interested in building their own reflow oven, I’ve made all my code, Fusion 360 files, and STL files available here: https://github.com/aBoyCanDream/Solder-Reflow-Oven.
The project is designed to be adaptable, with support for different displays, touchscreens, and thermocouple amps, but it will need the processing power of an ESP32 and above.
Additional Plans:
I’m considering developing a smartphone app for controlling the oven via iOS and Android, making the project even more versatile. Let me know if this is something you’d be interested in. And stay tuned to find out what that hatch in the front is for.
My BOM:
SSR: https://www.digikey.jp/en/products/detail/celduc/SO943460/14311190
TFT Capacitive Touch Screen (affiliate link): https://s.click.aliexpress.com/e/_oDafiE2 (Make sure to select the 3.5 inch with touch)
K-Type Thermocouple: https://www.digikey.com/en/products/detail/digilent-inc/240-080/5418219
Thermocouple Amp: https://www.digikey.com/en/products/detail/adafruit-industries-llc/4101/10245127?s=N4IgTCBcDaILYGMAOBOAbABgyAugXyA
ESP32 S3 (affiliate link): https://s.click.aliexpress.com/e/_oo6qXou (I recommend the N16R8)
C14 Power Entry Connector Receptacle: Power Entry Connector Receptacle
C13 Cable (if you’re in Japan or the US): https://www.digikey.com/en/products/detail/globtek-inc/3021453F701-R/16515731
International Plug Outlet: https://s.click.aliexpress.com/e/_om4UZNK
On/Off Switch: https://www.digikey.com/en/products/detail/bulgin/H8600VBACN/9598449
AC/DC 5V Module: https://s.click.aliexpress.com/e/_DFtXsr1
SSR heatsink (affilate link): https://s.click.aliexpress.com/e/_DlPeDcn