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Many electronic assemblers use standard solder having 60% Tin and 40% Lead. This formulation has a serious defect for electronic assemblers.
Alloy 60/40 has 3 (three) physical states. Solid, Plastic and Liquid, depending on the temperature of the solder. The problem occurs at the plastic temperature where the solder is plastic, grey and mushy. This state is apparent to the person soldering, by the dull gray grainy appearance of the solder joint. This can be improved by applying additional heat until the solder becomes liquid. This condition is responsible for bad and ugly solder joints.
A little known alloy, 63/37 has no plastic region and therefore produces only bright solder joints. Using 63/37, There is no need to overheat the solder joint to obtain smooth, bright solder joints and cold solder joints are reduced to a minimum.
The 63/37 alloy is called “Eutectic Solder”. It is produced by manufacturers such as Alpha, Kester and others. I have purchased it at Radio Shack some years ago, but have not tried to buy it lately. I bought a surplus 1 Lb. spool which will last for a very long time. Check eBay.
Caution: Do not confuse this alloy of tin and lead with Silver Eutectic solder.
Alloy 60/40 has 3 (three) physical states. Solid, Plastic and Liquid, depending on the temperature of the solder. The problem occurs at the plastic temperature where the solder is plastic, grey and mushy. This state is apparent to the person soldering, by the dull gray grainy appearance of the solder joint. This can be improved by applying additional heat until the solder becomes liquid. This condition is responsible for bad and ugly solder joints.
A little known alloy, 63/37 has no plastic region and therefore produces only bright solder joints. Using 63/37, There is no need to overheat the solder joint to obtain smooth, bright solder joints and cold solder joints are reduced to a minimum.
The 63/37 alloy is called “Eutectic Solder”. It is produced by manufacturers such as Alpha, Kester and others. I have purchased it at Radio Shack some years ago, but have not tried to buy it lately. I bought a surplus 1 Lb. spool which will last for a very long time. Check eBay.
Caution: Do not confuse this alloy of tin and lead with Silver Eutectic solder.
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