frying SMT components

[eccerr0r]

Has anyone fried any SMT components with a hot air gun?

Meaning, after soldering something to the board, it no longer works?

How about desoldering?

When trying to remove some components I've noticed that it takes a while to melt the solder... After that much heat for an extended period of time, I wonder when the breaking point is...

Perhaps I need to turn up the heat more? What about those SMT components that heatsink to the board? I tried pulling a "SMOOTH" chip off a HDD board, and didn't realize the bottom was soldered for heatsinking...

[clearchris]

Re: frying SMT components

I run my hot air at 325C at an airspeed of 5 out of 10. I can solder/desolder much quicker than when i ran at lower temps. Havent roasted anything yet.

[momaka]

Re: frying SMT components

I've used a blowtorch to remove MOSFETs and ceramic caps (among other components) from Xbox 360 boards just as a joke and contrary to my intentions... nothing funny happened - the MOSFETs and ceramic caps worked and were in spec once they cooled. Go figure. I still have them in my parts box.

I find it that not enough heat is often as bad as applying too much heat. With the former, you often end up breaking pins of pulling pads because the solder is not completely molten. Actually, the only thing you really want to avoid overheating are large BGA chips, because the heat can cause too much internal stress on the die (due to materials expanding and contracting with heat).