Reflow Oven

Introduction - Controleo3 Reflow Oven

Danger Toaster - Not for toast! This oven is a heavily modified toaster, intended for performing reflow soldering on surface-mount printed circuit boards. It can also be used as a programmable heat chamber, and can easily be used to bake moisture out of parts, salt re-melt 3D prints, etc.

Running a Bake Cycle

It is recommended to do a pre-heat bake to 50C/60C prior to starting the reflow cycle, as this greatly reduces the possibility that the oven will fail to ramp quickly enough. This is more effective with your boards inside of the heat chamber as well, but for smaller boards it is not necessary.

  • Select "Bake" from the main menu

  • In the "bake" screen, select "edit" to adjust the temperature and time. It's like a normal oven, but better.

  • This display will persist while the bake is running, counting down the time and displaying the current temperature.

Running a Reflow Cycle

  • Find a non-flammable surface clear of flammable materials to place the oven on, and plug it in.

  • Turn the lowest knob to as high of a temperature as it will go. This is an emergency thermal cutoff, which will trip if the oven enters a thermal runaway condition (unlikely, but bad!)

  • Once the system powers up, the screen to the left will be displayed. Select "Profiles".

  • Under "profiles" you will see the following screen. If this is the profile you would like to use, press "Run Profile"

  • To select a new profile, select "Choose Profile" and use the arrows to cycle through the available profiles. If you would like to add a different profile, please follow the instructions outlined in the lower sections

  • As soon as "Run Profile" is hit, the cycle will begin.

  • Once the cycle reaches the cooling phase, the door servo will push the door open. Clouds of flux smoke will come out, and the air will be very hot. Be careful! And don't even think about pulling the boards out just yet!

  • Once the oven has cooled a bit, the oven will let you know that it is safe to remove your boards. Be warned that they are still very hot!

  • After the oven tells you to remove boards, it will sit and wait until the oven temperature drops below a certain level (55C for this profile). After this occurs, the door will close, and the oven is ready for the next reflow operation.

Tips and Tricks

  • The oven will fail to reach target temperature if filled up with too many boards, as there is too much thermal mass. Pre-heating to 50C or 60C will help remedy this, as this stores up a bit of thermal energy prior to the reflow process.

  • This draws *tons* of power compared to a standard toaster. It is recommended to perform reflows while plugged into a direct 15A outlet - small gauge extension cords will get toasty, and reduce the effective thermal ramp rate of the oven

  • Do not try to remove boards as soon as they are done - it's best to wait for the little "i'm done!" jingle, as nothing ruins days faster than burning fingers on big ferrite transformer cores.

  • Flux fumes are nasty, and come out the door in clouds when the cycle ends. Avoid being right above the oven when this happens...

  • If you want to watch your boards reflow (I can't resist either!), get a super-powered flashlight and shine it through the opening in the door. It should give you just enough light to get good video.

More Information

For more information, and a much more detailed operation guide, see the Controleo 3 wobsite:

For instructions on how to design your own profiles, see this guide on the Controleo website. There's even a notepad++ language descriptor!

For any other questions, concerns, etc. please contact Alex Seiger on slack!

Build Pictures

The band-aid that was supplied with this Controleo3 kit was indeed used during construction...