Talking about solders... is there any advantage when using Sn60Pb38Cu2 over Sn63Pb37?

I've been using all my life Sn60Pb38Cu2, but now that the roll is about to get finished, I wonder if I should go for the good old eutectic alloy.

Never ever had a single problem with the Sn60Pb38Cu2, may be sometimes I get dull finishes, but I don't know if that's my alloy's fault or simply a consequence of mixing it with the lead-free solder that's in the board already "which very rarely remove completely".

The dull finishes will be due to the mixture of alloys. That‘s why it is better to repair with the same alloy as the original.
Small amounts of lead cause embrittlement.
Am I correct that Sn60Pb38Cu2 was marketed as “Savbit”?

 

The dull finishes will be due to the mixture of alloys. That‘s why it is better to repair with the same alloy as the original.
Small amounts of lead cause embrittlement.
Am I correct that Sn60Pb38Cu2 was marketed as “Savbit”?

I am not sure, this is my solder wire for the last 10 years or even more:



I love it, very good, super easy to use, at least for me.

 

The difference between 60% lead and 63% lead solders is real but not huge. The 63% alloy has the benefit of being an "eutectic alloy", meaning that as it is heated it transitions directly from a solid to a liquid that flows perfectly, while the 60% lead alloy enters a "plastic" state where it does not flow freely until it is a bit hotter. Sometimes that matters quite a bit.
The lead-free solder requires a temperature that is quite a bit higher and thus more likely to lead to PCB damage during rework. THAT is an actual problem for those who do repairs, component changes, and even fixing boards with poor solder joints.
Certainly it was not a part of the consideration which would have banned all lead solder alloys forever..

 

Certainly it was not a part of the consideration which would have banned all lead solder alloys forever..

Nor was the extra energy required to run the production lines at higher temperatures.

 

Lead free solder will never have the shiny, smooth surface but unlike lead-bearing solder the crystalline surface isn‘t the sign of a cold joint. I prefer 63Sn/37Pb for hand soldering and 60Sn/40Pb for tinning and don’t have any reason to go lead free—but if you can deal with the differences, including higher heat, RoHS compliant solder isn’t so terrible.

 

The difference between 60% lead and 63% lead solders is real but not huge. The 63% alloy has the benefit of being an "eutectic alloy", meaning that as it is heated it transitions directly from a solid to a liquid that flows perfectly, while the 60% lead alloy enters a "plastic" state where it does not flow freely until it is a bit hotter. Sometimes that matters quite a bit.
The lead-free solder requires a temperature that is quite a bit higher and thus more likely to lead to PCB damage during rework. THAT is an actual problem for those who do repairs, component changes, and even fixing boards with poor solder joints.
Certainly it was not a part of the consideration which would have banned all lead solder alloys forever..

63Sn/37Pb is very superior for hand soldering. It‘s lower melting point and complete immunity to cold joints is a serious advantage. On the other hand, 60Sn/40Pb has far superior wetting action than the eutectic alloy. So, in the case of tinning, it is the better choice. This is why bars of solid 60/40 alloy are common—they are used in solder pots.

 

Lead free solder will never have the shiny, smooth surface but unlike lead-bearing solder the crystalline surface isn‘t the sign of a cold joint. I prefer 63Sn/37Pb for hand soldering and 60Sn/40Pb for tinning and don’t have any reason to go lead free—but if you can deal with the differences, including higher heat, RoHS compliant solder isn’t so terrible.

How do you see then these images?

Post #40:

https://forum.allaboutcircuits.com/...-everything-lead-free-now.200205/post-1902540

 

How do you see then these images?

Post #40:

https://forum.allaboutcircuits.com/...-everything-lead-free-now.200205/post-1902540

That’s what I was responding to.

 

I have seen very poor and cold soldered joints done by those with no skill and it did not seem to matter what solder alloy they used. Practice, knowledge, insight, and skill are the primary requirements. Better solder and equipment certainly help speed things along, of course.

 

That's only if it we breath or ingest small particles, or it gets dissolved in our drinking water.
I highly doubt there are very many that have ever had significant lead intake from soldered connections.

The removal of lead in solder was just overreaction by politicians who heard that lead is bad.
It pales in comparison to the 4-5 million tons of lead put into the environment from the use of leaded gasoline since the 1920's until it was banned.

The very act of soldering liberates lead into the environment Cruts.

Spare a thought for bullets too, all lead. Not to mention aerosolized depleted uranium, truckloads of this filth is being shipped to Ukraine and Zionist Israel every week and used with devastating results (denser than lead and harder than steel).

 

The very act of soldering liberates lead into the environment Cruts.

Spare a thought for bullets too, all lead. Not to mention aerosolized depleted uranium, truckloads of this filth is being shipped to Ukraine and Zionist Israel every week and used with devastating results (denser than lead and harder than steel).

That's BS and displays a great about of ignorance and/or deliberate disinformation. What's the vapor temperature of lead or that of common lead solder alloys? Elemental lead is almost completely water insoluble. What's really dangerous are inorganic lead compounds.
https://blog.sra-solder.com/knowledge-base/lead-solder-safety

The depleted uranium conspiracy makes for a full BS dinner.

"If you're in a vehicle that's hit by a depleted uranium round, the radiation is the least of your worries" Well, you won't have any worries because you would be dead, very quickly.

The real environmental weapon is the WP being used by Russia on the general population.

 

That's BS and displays a great about of ignorance and/or deliberate disinformation. What's the vapor temperature of lead or that of common lead solder alloys? Elemental lead is almost completely water insoluble. What's really dangerous are inorganic lead compounds.
https://blog.sra-solder.com/knowledge-base/lead-solder-safety

The depleted uranium conspiracy makes for a full BS dinner.

"If you're in a vehicle that's hit by a depleted uranium round, the radiation is the least of your worries" Well, you won't have any worries because you would be dead, very quickly.

The real environmental weapon is the WP being used by Russia on the general population.

Try checking just a little, before rashly blabbering

https://www.sciencedirect.com/scien... aerosols,following inhalation of DU aerosols.

 

The very act of soldering liberates lead into the environment Cruts.

Spare a thought for bullets too, all lead. Not to mention aerosolized depleted uranium, truckloads of this filth is being shipped to Ukraine and Zionist Israel every week and used with devastating results (denser than lead and harder than steel).

I suggest looking up the vapor pressure of lead at normal soldering temperatures. It does not evaporate during normal soldering. And very few folks use a large torch to unsolder or rework PCBs. And probably none of the manufacturers do.
And the primary danger of bullets is while they are still hot and flying rapidly.
I also suggest considering the wisdom of picking a fight with anybody able to respond with terrible force.

I once got some good advice from an old hillbilly gentleman, who advised me: "Never pick a fight with an angry man with a gun in his hand." While the wisdom of that advice was clear to me, it appears to have not been apparent to some others.

 

The original premise was concerning landfill. I think the idea was that whilst lead doesn't dissolve in water, the pH of landfill was anything other than neutral. Now they are filling landfill with lithium batteries, because no-one is recycling them. The electrolyte is lithium hexafluorophosphate which decomposes into lithium fluoride, hydrofluoric acid, and phosphoric acid, neither of which I fancy in my drinking water.

 

OK, and what I see is that the problem is "farther down-hill" : The original premise was concerning landfill. None of the electrical things should be going into a landfill!!!! Recycling is the solution, and possibly even demanding that products not be such poor quality BY DESIGN! When the design goal is for the product to be obsolete in six months and to fail in eight months then certainly there is a problem more basic than lead solder use.

 

The original premise was concerning landfill. I think the idea was that whilst lead doesn't dissolve in water, the pH of landfill was anything other than neutral. Now they are filling landfill with lithium batteries, because no-one is recycling them. The electrolyte is lithium hexafluorophosphate which decomposes into lithium fluoride, hydrofluoric acid, and phosphoric acid, neither of which I fancy in my drinking water.

Lead batteries have higher recycle rates than 10 cent bottles and cans by local drug addicts.

We don't want to waste a valuable resource like lead but I never seen a study where electronics solder related lead has naturally leached from a landfill. The real danger is and was lead compounds in fuel, paints and processing wastes being dumped into the environment intentionally.

 

OK, and what I see is that the problem is "farther down-hill" : The original premise was concerning landfill. None of the electrical things should be going into a landfill!!!! Recycling is the solution, and possibly even demanding that products not be such poor quality BY DESIGN! When the design goal is for the product to be obsolete in six months and to fail in eight months then certainly there is a problem more basic than lead solder use.

Yes, but it doesn't mean it isn't happening:
https://www.bbc.co.uk/news/uk-england-cambridgeshire-66617760

 

I never seen a study where electronics solder related lead has naturally leached from a landfill.

I did once have the references. All I remember is that it was done in a "simulated landfill" and it look an awful lot like the EU paid to have the result that they wanted. Someone with an interest in lead mining paid for the contradictory study.

 

I have suggested the solution for recycling electronic stuff a few times, which is the one that has worked for the bottle types that it has been applied to, and still needs to be applied to all the rest of beverage bottle types.
That would be a deposit charge at the time of purchase, refunded in full at the time of returning. If there were a $10 charge for each cheap junk music player device we would never see another one at the curb for trash pickup, nor discarded TV sets or computers or monitors. The secondary benefit is that those folks who can't keep jobs would get money for doing something useful.

 

I have suggested the solution for recycling electronic stuff a few times, which is the one that has worked for the bottle types that it has been applied to, and still needs to be applied to all the rest of beverage bottle types.
That would be a deposit charge at the time of purchase, refunded in full at the time of returning. If there were a $10 charge for each cheap junk music player device we would never see another one at the curb for trash pickup, nor discarded TV sets or computers or monitors. The secondary benefit is that those folks who can't keep jobs would get money for doing something useful.

Would then people break into your house, steal all the power supplies that they find plugged into the wall and turn them in for $10 each? (then spend the money on drugs)