question about soldering irons (in reference to pcb boards)

[Boonesmi]

lately ive been doing more and more soldering on motherboards and video cards (ie. replacing bulging caps, etc)

buy my soldering iron kinda sucks 🙁 its like 10 yrs old and an old radio shack 25w which takes forever to get hot

im wanting a new one, but not really sure what would be best. any suggestions? how many watts is best? whats to many watts? what is to few watts? also. what temp is best for working on motherboards? whats to hot? whats not hot enough?


my main concern is that i dont want to get one so powerful/hot that it will damage the pcb boards.

suggestions?

 

[kornphlake]

I use Weller soldering irons at work all the time

http://www.cooperhandtools.com...l.cfm?upc=037103001146

I believe the tip shape ultimately determines the temperature for all but the most sophisticated irons. Generally the iron I use is set to about 700 deg F. I don't know what wattage we use, in the end all that a higher wattage will be good for is a faster heat up, any good iron should heat up in about a minute. 700 isn't quite hot enough for solders with a high silver content or for soldering on heatsinks and other highly conductive pieces with a large surface area, in these cases you'd see some advantage to a higher wattage soldering iron because it would have enough power to put heat into the heat sink.

You really need to know something about the components you are soldering to determine what is the best temperature, some components are quite sensitive to heat and will be damaged unless certain precautions are observed when soldering. My first job was soldering wire leads on a diode rectifier, because of the sensitive nature of the diode we put an alligator clip on the lead between the solder joint and the diode to act as a heat sink and keep the diode from overheating. Lots of modern SMT components and newer components complying with the new lead free standard being established in europe are less sensitive to heat.

 

[LTC8K6]

I still use an old Weller soldering iron with a temperature controlled tip. 25watts is plenty and it may really be too much for small pc board work.

Most likely, it is corrosion that is causing your old iron to take a while to heat up. Make sure there is no corrosion where the tip attaches to the iron. If it's threaded, clean the threads good. If it 's held in by a screw, then remove the screw and clean the tip thoroughly where it enters the iron. The tip needs to make good contact with the iron to heat up quickly.

This usually cures a slow heat up.