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I do most of my soldering with/directing children and so we always using lead-free solder (and thru hole and nothing too complicated).

I have a soldering iron station that has two settings, 20W & 40W - the 20W seems a little low to melt the solder and the 40W warms up the handle enough that the children want to stop before finishing the project. The tip also seems to get messed up (one side melts better than the other).

What range of watts would be best for lead free solder usage?

I understand the melting point of my SnAgCu solder is around 217 C, and that power and temperature are completely different pieces of information. My question still stands as is because a) the station I have doesn't list a temperature (and isn't temperature controlled), and b) many lower-end stations do not have a temperature controlled feature, only a listed power output range.

Are there any other specs or features of a station that should be considered specifically for lead-free usage? (e.g. tip size or shape)

Also, is this issue with the handle getting too warm a normal thing or do I just have a cheap iron?

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  • \$\begingroup\$ Shopping questions are off-topic for this site, but 300-350°C is around where leadfree solder melts. Power (Watts) can't be converted to temperature, trying is a stab in the dark. So try to cough up the money for a proper temperature controlled iron like that Hakko (I've heard that one is good value for money) if you can. And yeah, a good soldering iron will keep a cool handle even after prolonged on time. \$\endgroup\$ – Dampmaskin Apr 18 '17 at 17:51
  • \$\begingroup\$ athletic tape / bandage on the handle make it thicker, less slippery, and cooler; good for kids. \$\endgroup\$ – dandavis Apr 19 '17 at 2:55
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The main thing you need is knowledge of the tip's temperature, not "what power am I pumping into it", as that is a parameter with no function, as will possibly also become clearer a bit further.

Decent brands will very likely keep existing and usually have replacement tips nearly infinitely. My personal preference is Weller (by Cooper Tools). To name an example their WTCP series of devices and tips and replacement heating elements are more than 30 years old and still available. Decent brands do that, because they know quality and service are still appreciated in these job segments.

Again referencing the WTCP, also known as MagnaStat, we knew the tip cannot be given more than 48W in those, but they used the paramagnetic properties of a material to make a tip that would regulate the temperature itself. Tips came in a range of numbers from 1 through 0, where a higher number meant a higher temperature. All you had to do was change the tip to get a different temperature. Since 30+ years ago making actually adjustable soldering stations was an expensive hobby, this was the next best thing.

For my demo ware and workshops I still use and maintain 6 MagnaStat soldering stations, though they are a bit closer to $250 each, their longevity makes up for it easily to me. One of them actually is 22 years old.


As a side note: I use the MagnaStats, even though the WSD series is hardly more expensive and has a settable temperature, because there's nothing a young child can screw up. I used to bring my WSD81 along with the two MagnaStats back before I bought the new ones and on the WSD81 I could lock the wheel (no longer an option I believe) with a key, but it took less than 3 workshops for the teeth on that wheel to become smooth in the 200 to 400 region. I have also had to replace that knob when it got ripped off and was lost "because it didn't rotate properly". Then when you leave it unlocked, you get loads of overhead of kids first turning it to 150 and then complaining that it doesn't work, or turning it to 450 and having hot flux burst out onto their hands.


All that said, will the handle get warm? Yes. The handle is holding something that's several times the boiling temperature of water, it will be at the very least slightly warmer than ambient. Will it get annoyingly hot? That depends on the brand. When the brand allows "20W or 40W" as "temperature" settings, I give it higher chances that it will become annoyingly hot than those brands that actually realise what units normal people use for temperature. The heat that leaks away into the handle depends a lot on the construction and between brands and even between series within the same brand that will differ. However, again, a decent brand will make sure the handle never gets warmer than, say, a hot bath and will usually restrict themselves to a thermal rise of 5 Kelvin under normal circumstances.

Whether you need a certain wattage, again, depends on the build of the soldering iron and the tip. If a lot of energy gets lost on its way to the tip, for lead-free you'll quickly need 60W to work comfortably with lead-free solders. On the other hand, with my Weller Micro-soldering iron (I have about 10 Wellers in my lab, if you also count the 6 demo units), it's only 35W and works fine for lead-free (small traces and what not), without even getting the handle slightly warm, because it creates all the heat right at the tip.

So, what I suggest is you find a website in your region and language that allows you to list and sort soldering stations. Find a group within them that allow you to actively decide temperature, either with a control knob or by replaceable tips. Because then the maker of the device thought about temperatures and what they mean, not even because you want to adjust it. And sort for cost.

Pick out the ones that seem and sound good to you and find reviews from reputable bloggers or reviewers like Mike's Electric Stuff, or the EEVBLOG's Dave Jones. They don't know everything, but they have worked a lot with those kinds of devices and will at least easily sort out the absolute worst crap.


For lead-free contact soldering I personally prefer a tip-temperature in the 320°C to 340°C with a good soldering iron that gets the majority of heat into the tip. If they are large objects or the iron is a bit hinkier you may need to set it to 360 or 370°C to compensate for the high losses between heat-sensor and tip.

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You should be able to get a temperature controlled station in that price range that lets you dial in whatever temperature seems appropriate, and providing it is temperature controlled more power is usually better then less. Professionally I use an 80W iron, usually set to somewhere in the 330 Celsius or so region and with a suitable choice of tip it is never too powerful even when working with small SMT parts.

I question your 'lead free' call there, the flux used in the lead free compositions is much nastier then the flux in the leaded stuff, and it far more then the lead is IMHO the health hazard to be concerned by. Not a problem for machine soldering, but for hobbyist hand soldering I would go leaded personally (It is also easier, works at a lower temperature (So less chance of beginners lifting pads) and gives a better looking board).

Lots of fake Hakko gear out there from the usual suspects, at widely varying price points and qualities, some of it is not totally awful. If second hand is an option then Hakko/Weller/Pace are the names to conjure with, just be careful about the fake gear thing.

I have a Weller WSD81 that I got second hand, but that is because I work with it, there are plenty of other good choices out there.

Do your kids a favour and use good solder, it is NOT all created equal, and some is simply awful to work with.

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    \$\begingroup\$ While you are right on average that more lead-free comes with horrible flux (my demo gear also features blowers and filtered suckers) not all of them do, and if you do public demo in many, many places in the world, as I know personally, you are barred from using any lead without having waivers signed. Good luck getting a 7 year old to legally sign one. \$\endgroup\$ – Asmyldof Apr 18 '17 at 18:05
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    \$\begingroup\$ +1 @Asmyldof for not all lead-free solder has badly hazardous flux. In point of fact, good old-fashioned alcohol+pine rosin flux still works quite nicely with my Pb-free, silver-bearing solder I use for my SMT work. I use it the same way it's been used with PB-based solder for decades: dab on a bit of flux; apply iron & solder; done. \$\endgroup\$ – Robherc KV5ROB Apr 18 '17 at 19:48
  • \$\begingroup\$ @RobhercKV5ROB Thx. I myself have several types of solder, but all non-rosin. Partly because doing 01005 with rosin gets messy very quickly, partly because rosin makes me wheeze in the case I forget to turn on the vacuum. But my 0.4mm 97/3 PBF has non-aggressive and I have self-filled flux brush-tips with same. \$\endgroup\$ – Asmyldof Apr 18 '17 at 20:14
  • \$\begingroup\$ "I question your 'lead free' call there, the flux ... is much nastier..." Nasty flux is definitely a problem, but so is lead, and especially for children. Why especially for children? 1. Because they are less likely to avoid touching their mouths/noses/eyes/etc without first washing their hands. 2. Because they have shorter arms and are therefore likely to be breathing closer to the part being soldered. 3. Because lead is more bio-available for children (strange but apparently true). 4. Because children potentially have more life ahead of them in which for lead poisoning to manifest. \$\endgroup\$ – sampablokuper Feb 26 '19 at 4:39

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