Toaster Oven Reflow Soldering (BGA)

Step 1 Find a toaster oven.

You're looking for two main things, an adjustable temperature knob, and a timer that will time down. The more precision you can get in the timer the better.

Also, if you can get it, some sort of forced air flow will improve the uniformity of the oven temperature, but you have to make sure that the air flow isn't powerful enough to move your components around.

Comments

[bucklipe]

What about an external motor with the fan shaft going through the bottom(?) with a speed regulator. This way the fan blades could be aluminum and large enough to move the air slowly. With the motor mounted outside the limiting factor would be the melting point of aluminum, not a factor with the temps used for solder.

[ZBM]

question : for a forced airflow would two holes cut in one at say the top left and at the bottom right with a PC fan attached at one of the holes work?

[dUc0N]

I can understand where you're going with that, but it'd probably hurt more than help, as the fan would be pulling cooler air from the room into the oven, and then forcing nice hot air out the top. A better solution (if you want to mod it yourself) would be to come up with a fan that can withstand the temps you intend to use the oven at (plus a good safety margin, an additional 10-20% or so), installed on the inside of the oven. The best positioning would probably be right at the top, aimed down, where it'd suck the hottest air from the top and channel it directly onto the part you're working with.

[sparr]

I want to stress that the airflow should be *VERY* slow. You are not trying to bring more air in contact with the part (which is what small fans normally do, like on heat sinks). You are just trying to even out the temperature of the air, like a ceiling fan.

Imagine a computer case fan spinning at 100RPM instead of 2000RPM. Except a computer case fan would melt in a toaster oven, but you get the idea.

[ZBM]

thanks for the input

[colin]

Actually, you probably want to avoid blasting the air straight onto your board. There's nothing worse than having components slide around when the solder is molten. That being said, a gentle breeze should be fine.

[dUc0N]

Point taken, especially considering the fact that you're the experienced one. =-)