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FYI in my experience the SRA FAST CHIP SMD Removal Alloy is an invaluable tool for all my solder rework, not just SMD chips.

On one rework occasion I needed to move a capacitor that I had already soldered and lead-trimmed.? I tried applying solder flux then using solder wick over each PCB bottom pad but couldn't clear out enough solder to remove the capacitor.? Using the "SRA Fast Chip Removal kit" I applied solder flux, then applied a drop of the low temperature solder alloy from the kit over both pads, then quickly applied solder wick and heat.? It sucked the solder out onto the wick allowing me to remove the capacitor undamaged!

I've had similar experience with putting solder in a nearby pad instead of where I wanted to.? Same trials as above with similar results.? It sucked the thru-hole clean of the undesired solder onto the solder wick.

I paid $10 for this kit on Amazon, which comes with about 30" of low temp solder plus a small container of solder flux.? Since I've only used a drop of the solder of each pad I've reworked, it doesn't seem that expensive to me.? The hassle-free, undamaged PCB Pads, thru-holes, and components makes this my "go-to" solder rework option.

Low temperature alloy is wonderful stuff.? Gets parts off the board without damaging the board or the part.? I've removed a couple QFP (quad flat pack) surface mount devices.

I was getting low on my first purchase of it.? I did a few google searches to see what the alloy was.? Then I found this on Amazon:

which is fairly close equivalent.? Bismuth, lead, tin.? Just be sure you don't buy an alloy with cadmium.? Toxicity.

I admit that having your desoldering alloy in an ingot is really inconvenient.? Wire is much easier to handle.

I have an antistatic mat made of silicone that I work on.? Like this:

Certainly it's heat-resistant enough.? It has some small compartments.? By positioning the mat at an angle I could provide a trough.? Into that I melted the low-temp alloy, by holding my hot soldering iron on the ingot and melting some off so it dropped into the trough.? It's not pretty, but you can form usable sticks of the alloy.

Very inexpensive; $16 for a pound.? You'll never run out.? Give some to your ham buddies.

You got me thinking Rich:
- I've been a fan of Chip-Quik low temp allow for years, but it is crazy expensive per foot
- One pound of the alloy ingot is a lot!
- Most medical grade plastic syringes have no trouble being sterilized in boiling water/steam

So, I'm going to try loading up a syringe with some small chunks of that alloy (just ordered), drop them into a syringe and let it sit for 15 minutes or so.? I should them be able to extrude fairly small "wire" onto a silicone mat, or straight into ice-water.

I'll let the group know how it comes out!
73,
--
Brent DeWitt, AB1LF
Milford, MA

I'm interested in seeing how well this works. Let us know please.
73,
Dean - KC9REN