What temp?

[BobH]

OK I was just given a nice new Weller digital solidering station but what temprature do I use for pc board work? Sometimes ignorance is bliss. Bob

[jwax]

Nice gift! Start around 600 F, increase to 700 F if needed. Higher yet for more massive devices.

[Dean Huster]

Soldering has so many variables that you can't just specify a temperature. Temperature, mass of the joint and mass of their iron tip all figure in together to determine the proper temperature. Pace, Inc. says temperature isn't the issue and that your normal PCB connections should be completed in about two seconds. If it takes longer than two seconds, increase your temperature or increase the size of your tip (the heat storage capacity). If the joint takes a second or less to complete, your tip is too hot and/or your tip size is too large. If temperature is the only variable you can control with that iron, adjust the temp for a two-second joint.

Dean

[rshayes]

One of the basic variables is the type of solder. The lowest melting point for Lead-Tin solder is the 63/37 alloy, sometimes called eutectic solder. Next would be 60/40, followed by 50/50. Most of the solder you see these days is either 63/37 or 60/40. Older equipment, from the 1960s or before, will probably be wired with 50/50 solder and need higher temperatures.

The 600 degree setting may be a little on the low side. Weller used to make irons where the temperature was controlled by the tip selected at either 600, 700, or 800 degrees. The tips were made of an iron alloy, so the thermal conductivity was not particularly high. The 600 degree tips would often cool down below the melting point of the solder. This would result in the soldering iron being soldered to the connection. You then had to find a hotter iron to unsolder the first soldering iron. Its a rather awkward situation.

With a variable temperature iron you can simply increase the heat setting and wait a minute or to for it to take effect.

The 700 degree irons usually worked fairly well. The 800 degree tips would usually oxidize the solder on the tip fairly rapidly when they were idle.

Someting in the 650 to 700 degree range is probably a good starting point. If the copper area connected to the joint is large, such as a ground plane, a higher temperature may be necessary.

<small>[ March 09, 2006, 10:09 PM: Message edited by: stephen ]</small>

[Dean Huster]

The best iron I've ever used is a tiny, 15-watt, non-temperature-controlled Antex (made in the UK) iron. Gets hotternell idling, but there isn't hardly any joint short of ground planes that you can't use it on. Seems to me the last one I saw in a catalog was $50 or so, so they weren't cheap for what they were. I got my Ungar #777 handle stolen by a student a few years ago, leaving me with a large assortment of elements with no handle. Now, talk about an iron that could handle soldering ground planes AND PL-259s.

Dean

[Robert Reed]

I have been using a 35 watt Imperial "princess" for years and it has worked out in all PC applications. Too little tip heat is worse than too much tip heat in my opinion. You want contact for a second or two and then see a nice flow, at that time release.

[pebe]

Originally posted by Dean Huster:
The best iron I've ever used is a tiny, 15-watt, non-temperature-controlled Antex (made in the UK) iron. Gets hotternell idling, but there isn't hardly any joint short of ground planes that you can't use it on. Seems to me the last one I saw in a catalog was $50 or so, so they weren't cheap for what they were. I got my Ungar #777 handle stolen by a student a few years ago, leaving me with a large assortment of elements with no handle. Now, talk about an iron that could handle soldering ground planes AND PL-259s.

Dean

I remember the Antex well. We overcame the excessive temperature during idle periods by fitting a microswitch to the stand, that put a 1N4007 in series with the mains lead when the iron was on the stand. It cut the idle power by half.