Solder temperature?

prof_braino

I just started on a variable temp soldering iron. http://code.google.com/p/propforth/wiki/VariableTempSolderingIron

based on various article, like this one from hackaday http://hackaday.com/2008/08/05/how-to-the-hackers-soldering-station/

So far its cost $11 and has not caught fire.

After reading, it turns out there' a zillion differnet solders and aeach has a different melting point.

So what temperature do you usually use? Previous, I just used LOW when it worked, and HIGH other wise. (Which it turns out might be 183C and 250c respectively if I measures right). Are these the right temps for old (hobbyist) lead solder and new new lead free solder?

LoopyByteloose

I use a cheap 25 watt iron without temperature control. ... no idea what temperature it is at. But if I need more heat, I let it sit awhile between tasks. This is not only about the control of the temperature for the 'heat stored' within the tip. Temperature control may save money for tips when you leave it on all day at the bench, but I don't do that.

The new lead free solder is higher temperature than the lead-tin alloy. And there is a metal - I guess antimony - that is used to lower the solder melt temperature for desoldering sensitive boards. Plus, too much heat or too high a temperature will pull copper foil off of boards.

Still I find the simplest way to control temperature is to chose a lower watt soldering iron for delicate work. If I get into SMD work, I may buy a 15 watt iron or just use a light dimmer switch to lower the available power to the iron.

RDL2004

About 625F - 650F for regular (63/37) solder and around 700F - 725F for lead-free works pretty well. I actually will often run higher because it seems quicker and I think the parts don't get heat stressed quite as bad.

Bobb Fwed

We run around 650-700F. But as RDL said, often running higher (our irons go up to 850F) to help speed certain operation up. Just be careful of heading an individual part or pin too much.

SRLM

I solder with lead solder at 320C for the soldering iron, 320C for the hot air gun, and 220C for the toaster oven.

WBA Consulting

I always use 700 or 800F tips but more importantly, I choose the tip that matches the pin/pad I am soldering. "Heat Transfer Timing" is more important than the temperature used. I also work to the unwritten rule of using the lowest temp that gets the job done properly.

Leon

Yes. I use Metcal equipment and they recommend a tip that matches the object being soldered:

For STTC soldering tips, you want to pick a tip geometry which will maximize
contact with the connection. A flat, blunt tip will transfer more heat than a fine,
pointed one. Choosing the largest tip possible will both improve performance
(enabling you to get more heat at lower temperatures), and enhance tip life.

I use 600 series (675F/352C) and 700 series (775F/405C) cartridges for lead solder. The 700 series are for use with power and ground planes.

Gareth

"Feel the joint, - Luke" -
I don't as a rule check the temperature ... however i am constantly twiddling the temperature control to suit the need of the moment.

check the quality of the soldering joint by joint.

If its silver/mirror like (+minimal smattering of flux) then temperature is ok .....
If its a dull/slightly grey texture (maybe crackles) then temperature is too low (heading in a "dry joint" direction).
If its pitted or bubbles during the soldering process then wind the temperature down. (this also give a "dry joint").
Boiling the flux out of the joint (too high temperature) before it wets the joint will also give bad results.

I get best results with high lead content solder (unfortunately)

Dr_Acula

Like SRLM, I'm happy with 320C. I set the knob to that temperature about 20 years ago and haven't changed it since.