Print PDF
Favorite
Email
Step 2How much wattage do I really need?
One question I never got a satisfying answer from RadioShack was "How much wattage do I need?" What's the right temperature to solder at? How does wattage relate to temperature? What is the recommend soldering temperature?
Answer: Wattage is how much heat can continuously be supplied by the iron. This is, in principle, independent of the tip temperature. On expensive irons, the heat (wattage supplied to the tip) is throttled to maintain a certain tip temperature. The wattage is really a maximum heat output. However, cheaper irons contain a simple heater that is always generating the rated heat, so tip temperature can vary widely. A 15W may only reach 550 degrees F, whereas a 40 Watt can get over 800 degrees.
In general, manufacturers recommend soldering temperatures to be between 650 and 750 degrees F for lead-based solder, and maybe up to 800 degrees for lead-free solder. But why is this if solder melts below 400 degrees? The larger the temperature, the quicker heat will transfer to your parts, so higher temperatures speed up soldering. You could solder at 450 degrees, but this would require some patience. On the other hand, soldering at 1000 degrees would lead to a number of other problems. Parts would be more likely to burn out, the board could be damaged, flux would boil off too fast, soldering tips would burn out quicker, the joints would become more brittle, and the lead would be more likely to atomize and float around in the fumes. All these factors are why many recommend soldering at the lowest temperature possible, but you have to balance the above concerns with the speed that you can solder.
Answer: Wattage is how much heat can continuously be supplied by the iron. This is, in principle, independent of the tip temperature. On expensive irons, the heat (wattage supplied to the tip) is throttled to maintain a certain tip temperature. The wattage is really a maximum heat output. However, cheaper irons contain a simple heater that is always generating the rated heat, so tip temperature can vary widely. A 15W may only reach 550 degrees F, whereas a 40 Watt can get over 800 degrees.
In general, manufacturers recommend soldering temperatures to be between 650 and 750 degrees F for lead-based solder, and maybe up to 800 degrees for lead-free solder. But why is this if solder melts below 400 degrees? The larger the temperature, the quicker heat will transfer to your parts, so higher temperatures speed up soldering. You could solder at 450 degrees, but this would require some patience. On the other hand, soldering at 1000 degrees would lead to a number of other problems. Parts would be more likely to burn out, the board could be damaged, flux would boil off too fast, soldering tips would burn out quicker, the joints would become more brittle, and the lead would be more likely to atomize and float around in the fumes. All these factors are why many recommend soldering at the lowest temperature possible, but you have to balance the above concerns with the speed that you can solder.
| « Previous Step | Download PDFView All Steps | Next Step » |
 |
Add Comment
|
