Upside down bga reflow?

[tvtimmy]

I've been thinking about this for a while. I've seen the infomercials about the NuWave Precision Induction Cooktop unit, and was wondering if I could set it to about 450° f and put the mainboard on it BGA side down and reflow the chips. Could this work ?

[diif]

Re: Upside down bga reflow?

No, it's an induction cooker. https://www.cda.eu/hobs/how-does-ind...-cooking-work/

[tvtimmy]

Re: Upside down bga reflow?

I thought the metal top of the chips would conduct the heat.

[diif]

Re: Upside down bga reflow?

The tops of the processors in LGs and Samsungs are non ferrous, I'm guessing aluminium.

Even if it did transfer the heat, I think the weight of the board pressing down would deform the balls.

[momaka]

Re: Upside down bga reflow?

What diif said. ^

The induction cooker will only heat metal parts made of ferrous metals (i.e. iron, steel, etc.) Nothing else will react.
Also, the inductive field could (and very likely will) generate substantial currents through the PCB and possibly kill something on the board.

So again, that's a big NO.

Even if it did transfer the heat, I think the weight of the board pressing down would deform the balls.

Yup, and then there's that too. ^

So even if this was not an inductive heater, but instead a regular IR/element heater, the answer is still, No, it won't work.

[tvtimmy]

Re: Upside down bga reflow?

The idea has been wiped from my thinkmeat(brain). At least I won't have to buy the NuWave.

[clearchris]

Re: Upside down bga reflow?

Can confirm. An employee put a digital scale on the induction cooker when off. Something fell and hit the button to turn the induction cooker on. It was on for maybe a few seconds, that scale was completely destroyed.

I don't let anyone put anything other than a pot on the induction cooker anymore.