Mostly I just use a normal Pb solder to dilute whatever solder a manufacturer cares to use but I keep a roll of 2% silver mix that I bought 20+ years ago. Infrequently I need to drag it out these days now I have a pretty ordinary soldering station but it has saved the day many a time in the past. It was 2-3x the price of Pb solder and that ratio hasn't changed much but despite the price when I run out (unlikely) I'd have no hesitation in getting more.
Forget the price and just get some, the wallet and regret won't remember when you really need it !
Although you're right, the ROHS lead free solder requires a LOT more heat. Is that what you mean by having some 2% silver tin and lead solder?Mostly I just use a normal Pb solder to dilute whatever solder a manufacturer cares to use but I keep a roll of 2% silver mix that I bought 20+ years ago. Infrequently I need to drag it out these days now I have a pretty ordinary soldering station but it has saved the day many a time in the past. It was 2-3x the price of Pb solder and that ratio hasn't changed much but despite the price when I run out (unlikely) I'd have no hesitation in getting more.
Forget the price and just get some, the wallet and regret won't remember when you really need it !
I have some silver solder, but I was specifically talking about for desoldering things like big SMD devices.
Worried about cost? How about pouring $50,000 of lead out onto the ground?
Then a PCB preheater and hot air is what you need.
I don't think your original question was actually answered (and my post also didn't help, sorry about that).
Low melting-point solders are principally composed of bismuth and/or indium. Bismuth is somewhat more expensive than tin, and indium is quite expensive, around half the cost of silver. But what we really want is a solder that can alloy with either Sn60Pb40, or lead-free, and form a combined alloy that is still low melting (and maybe has a wide plastic zone). I remember some user here from Eastern Europe said that he could buy some bismuth alloy very cheaply compared to what ChipQuik costs, but I don't remember the details.
Bismuth and indium are both "non-toxic", like silver or gold, although eating them isn't really recommended. You have to watch out because some low-melt alloys contain cadmium, antimony, or arsenic. The one that presents a particular concern is cadmium, which has been shown to be a workplace hazard even in the amounts absorbed as vapor from molten metal work. ChipQuik apparently does not, and seems to be the same as Bolton/Cerrolow 136 (which sells for $60/lb in bulk). ChipQuik SMD16 is 16 ft. of alloy (no flux) weighing approx. 2 oz, for $98: a markup of around 1200%, although drawing the wire has some cost.
A possible alternative is Field's metal, which has a similar melting point (144° F), although it is more expensive in bulk due to higher indium content. I'm not sure if it has good alloying properties with lead solder; I personally wouldn't use it for anything important without verifying this. One possibility is to buy an ingot of Cerrolow 136, and use a nibbler to chew off bits of it to melt onto SMD chips in lieu of wire solder. Making wire yourself requires drawing dies and is probably too expensive and time consuming.
Okay, so now I am convinced that Chip Quik and similar low melting point solders are a great thing to have around to get parts off of PCBs without heating them up too much.
What is the best deal on more than just a tiny bit thats not going to break the bank?
just need to be aware that we need to clean thoroughly the part removed with low melt because if we want to reuse the part and low melt solder still on its pin, solder joint will not be strong (brittle), so a one step more hassle in cleaning if using low melt solder. fwiw..