Re: [softrock40] Re: Si570 desoldering tips
- Hello Pete and All,
On 2/15/2010 Pete NI9N wrote:
>I just noticed this post, so I apologize for being a couple of weeks
>I have a technique that works very well for unsoldering surface-mount
>You will need a hot air tool, I use a Weller Portasol butane soldering
>with a hot-air blower tip. You will also need an electric griddle, which
>you can get for about $20 at any discount store. You may want an
>thermometer from Harbor Freight Tools or similar.
>Use the griddle as a hot plate to preheat the PCB. You'll have to watch
>the temperature to avoid damaging through-hole parts, this is where the
>thermometer comes in. When it reaches the desired preheat temperature,
>apply hot air. The solder holding the part you want to remove should
>melt almost instantly, and you can lift it right off. If you're
>replacing it, just place the new one while the PCB is still hot.
>More hot air to reflow the solder.
>Make sure you use a good hot air tool, NOT one of the little butane
>torches from harbor freight or similar, and use the hot air tip, NOT
>the blowtorch tip. You should see no flame.
>You can use an electric skillet instead of a griddle, but the griddle
>is easier to use because it doesn't have the sides.
You are right, It is a good method. But in the case of the Si570,
I had proposed a MacGyver's style solution:
On June 5 2008, in message # 21978, I wrote:
> It happens that I have soldered mine this week. But before soldering,
> I have devised a tip to unsolder it, just in case!
> So here is the story:
> The goal is to solder the Si570 at a small height (0.5mm for ex)
above the board.
> 1 - Put a small drop of solder on each of the 8 pads of the Si570.
> 2 - Make a U shape with a piece of .05 mm wire. I took 2 inches of
> wire wrapping wire (30 AWG/0.5 insulation diameter).
> 3 - Put the U on the board, place and solder the Si570.
> 4 - Remove the wire.
Here use a monospaced font(fixed-width) like Courrier New etc.
> | |
> X X
> ____| |_______________X <- wire soldered on a
> / | | pad or PCB track
> | X Si570 X to avoid too
> \____| |_______________X <- much move
> | |
> X X
> | |
> "If" I have to remove the chip, I will place a piece of magnet wire
> (30 AWG for ex) under it and unsolder one pad at a time by moving the
> wire while the solder is melted. A well known solution.
> (Once more it will be a good idea to fix one end of the magnet wire
> by soldering it on the board.)
As it costs nothing, I can't say it is my just my $.02 ... 73