Hi I want to manually assemble an electronic appliance I have much soldering to do.What solder should I really use? low thin -lead ratio. or high tin-lead ratio. Is there any that I can use also that will be best?
There are really only two types you would want to use for this application.
One is standard 60/40 (60% tin, 40% lead) or 63/37 solder suitable for electronics, the other is lead free electrical solder (generally a tin, copper and silver). Which one you use (ie- can buy locally) will depend on where you are as solder containing lead is not legally available in some places.
It all depends on what it is, where it will be used, and if your going to export it.
These days its getting more difficult to get hold of lead/tin solder due to the requirement for ROHS compliance at every level, hobbyists included.
Old hands like my self have been quietly stock piling "real" solder for our own use in our projects for some time now.
Lead-free solder is the preferred solder these days. Unless your device is for medical/aerospace or mining, which have ROHS exemptions.
The thickness of the solder only enters into it depending on what your soldering. Thin solder is used on circuit boards for soldering components. Thick solder is used when soldering wire(cables) to terminations.
Electronic solder is usually 60%Tin/40%Lead, when soldering on circuit boards a temperature of around 290/320 degrees Celsius is the norm. When using lead free solder the soldering iron will need to be much hotter in the 340/360 degree range. Now that is also dependant on the tip size and shape.
Small conical shape tips are good for circuit boards where as large wedge shaped tips are better for soldering cables and ground planes.
The best solder to use is the leaded one, but don't tell the greenies that your using it because they'll probably set up a protest camp on your lawn...
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There are two reasons for a man to do a thing, One that sounds good, and the real one...
"The best solder to use is the leaded one, but don't tell the greenies that your using it because they'll probably set up a protest camp on your lawn..."
Exactly, they don't even try to check the best output... but always ready for the protests...
The other posts adequately answer your question. I would add however, if any part of the soldered surface(s) in your "appliance" will touch either food or liquid meant for consumption, do not use any lead based solder.
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