On Saturday 29 May 2004 10:14 pm, crankorgan wrote:
> > I've seen those heat guns, never thought about using one to get
> > parts off a board, and didn't know that they reached solder-melting
> > temperature. It shouldn't be a surprise, though, since they'll make
> > paint bubble up pretty good...
>
> Roy,
> The machine for changing surface mount chips has a heat gun on
> both sides of the board. The nozzels move together. There is a
> temperature control. The company that makes them is called HART. You
> put a dab of stuff on the chip. When the stuff turns clear the chip
> will lift off. With the heat gun you preheat the bottom of the board
> and then go in for the kill from the top. I mount the board in a bench
> vise so it does not fall.
Sounds like a good plan to me.:-)
> Years ago people used a propane torch.
I think I may have tried that years ago, I don't really remember. I know my
brother tried it a while back, in his driveway -- the problem with that is
it's too darn easy to set the board on fire, and those fumes are pretty
nasty.
> I used to worry about hurting parts with heat until I saw a wave soldering
> machine and surface mounted parts being soldered in a toaster oven. Some
> heat guns also come with deflector tips to localize the air. The heat gun
> also works great with shrink tubing and bending plastic.
I used one for heatshrink when we were making "fans" to go on the end of
"snakes" (think audio, going between a stage and a mixing console somewhere
out in the audience area). A typical fan had 16 or 24 lines going down, and
3-6 coming back up, each one having a 3 foot length of heatshrink over it.
To try it any other way would've been ∗real∗ time-consuming...