Soldering Iron Temperature?

SteveJ

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Like most of you, I'm de-soldering and soldering quite a bit on old boards with old components --

What temperature do you set your soldering irons at? I'd like to make quick work of the soldering without damaging any parts.

Thanks!
 
650 is where mine sits. That's what was in the training I took years ago on Pace soldering/desoldering stations.
 
666...WHOOAAAA DEVILLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL


nah i run mine at 700... doing heavily corroded desoldering might even kick it up to 750...
 
I wound up having to desolder 2 control panels a couple months ago, one with half qd's and half solder, the other with all connections soldered (I'd like to find the op that did the latter one and choke him to death), between 650 and 700 seemed to be the range to get the solder to melt. Most of the time I sat at 650 with a big glass of patience, but a couple of them weren't budging below 700.
 
335. Although I am starting to suspect that might be Celsius...
Yeah. Celcius. ----> 635 F

I have a Weller WLC100 that I use for most things. No temperature settings on this beatie...just a 1-5 continuous range. I set it to a little more than 3 for surface mount stuff. About 3.5 for regular through hole assembly. Usually about 4 for through hole disassembly...though for old arcade board work I often crank it up to 5. For control panels and coin switches etc it goes to 5.

General rule of thumb for me: solder should melt within 2-3 seconds tops. "Hotter" is almost always better than "longer". As soon as the solder melts, the job is done and I take the heat away. I would like to just use the "5" setting. That would actually be the safest for those rare parts. Solder always melts around 370F (depending on the alloy) so the joint will get that hot, and no more, no matter what. But if you heat it slowly with a cold iron then the heat has time to travel up the lead and the part could be sitting at 350F really suffering for a long time. So heat it as fast as possible. The downside to this is wear and tear on my tip and heating element. That's the only reason I don't leave the thing up at 5.
 
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I use metcal 700F tips. The best advice is to use the lowest temperature that works for you after experimenting on some sacrificial PCBs. Too high and you can overheat the copper PCB traces and cause them to lift or separate from the PCB.


Bill
 
I use metcal 700F tips.
Same here. Metcal actually recommends 600 degree tips if you are using no-clean solder, but I've yet to try a 600 degree tip. It would be nice if it worked well though, because I like no-clean solder, and 600 degrees would be easier on the boards.
 
There are 2 questions here: what's good for my iron? what's good for my board? Sadly these are in direct conflict. But we're dealing with boards that mostly can't be replaced, so I choose hotter because that's actually *safer* for the boards. See my other post for the reasoning. There will always be differing opinions on the best iron temperature. Which is why I tend to recommend soldering time rather than a temperature. That's really the important factor.

Here's the rule of thumb: if it takes longer than 2-3 seconds for your solder to flow your iron isn't hot enough for the job at hand.
 
There are 2 questions here: what's good for my iron? what's good for my board? Sadly these are in direct conflict. But we're dealing with boards that mostly can't be replaced, so I choose hotter because that's actually *safer* for the boards. See my other post for the reasoning. There will always be differing opinions on the best iron temperature. Which is why I tend to recommend soldering time rather than a temperature. That's really the important factor.

Here's the rule of thumb: if it takes longer than 2-3 seconds for your solder to flow your iron isn't hot enough for the job at hand.

That's why I want to try a Metcal 600 degree tip with no-clean solder. BTW, my statement was conditional:

"It would be nice if it worked well though, because I like no-clean solder, and 600 degrees would be easier on the boards."

If it took an extra 2-3 seconds for the solder to flow then it wouldn't be working well.

Metcals have the fastest recovery times around, and the speed of recovery isn't affected by what temperature tip you are using. I wouldn't be surprised if a 600 degree Metcal tip worked just fine, especially since Metcal recommends it under certain conditions:

TEMPERATURE SELECTION

Start with a 600 Series tip. If your board is simple and does not have too many backplanes, use a 500 Series tip cartridge. If you are soldering or desoldering a heavy board with copper planes, you may want to use a higher temperature series. If you are removing a large component, you may need to use a 700 Series tip cartridge to accommodate the large load.

Choose the lowest temperature possible:

In general, Metcal systems use lower temperatures than conventional irons. Metcal can afford to use low temperatures since power delivery varies, depending on the size of the load. ŒDirect Power¹ allows soldering of heavy loads at low termperatures, by maximizing power (heat) to the load.

Take flux type into consideration:

If you are using a No-Clean flux, use lower temperatures. High temperatures will flash No-Cleans right off the board. Combining 700 Series tip cartridges and No-Clean flux will sharply reduce tip life. If you are using an RMA flux, you can afford to use a higher temperature series tip cartridge.

Is temperature important?

Remember, good contact, a wet connection, and the correct tip geometry are the keys to effective soldering. You want to maximize the efficiency of power delivery to the load, at low temperatures. Using low temperatures will lessen danger to the board, lessening your scrap rates. Raising the temperature should only be done as a last resort.

How do I change the tip temperature?

To change the temperature, you need to change the tip cartridge. Temperature is not controlled by the power supply. Temperature is constant, while power is variable.

Published by Metcal
Edited by Linden McClure, Ph.D.

Link
 
That's an awesome blurb. Thanks for posting it!
(one day, I too will have a Metcal rig....sigh...)
 
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