What soldering iron wattage?

[MAD Dave]

I am having to change my ESC connector to be compatible with the purchased LiPo's. It's an 80 Amp ESC so has pretty heavy supply cables that are acting as very efficient heat sinks! My current soldering iron is struggling and I am not happy with the ~dry joints it is producing. So, to attach 5.5mm barrel connectors to these cables, what wattage would members recommend please? Anyone have any favourite irons? A Maplin unit would be preferable, I could then collect it tomorrow from the local outlet and get on with my build........

[brokenenglish]

I've learned how to solder connectors over the last few years and there are some very informative videos on youtube, with all the advice and info you need.

[John Lee]

I bought & use an Antex 80 watt on EC5 connectors having found my 40 watt iron was not man enough for the job.

I bought my Antex 15 watt iron (for electronic PC board work) when I was a schoolboy, I'm now retired & it is still going strong so that's my preferred brand.

For other opinions there are numerous threads on the subject if you use the search field on the top right of this website.

[Mark Elen]

Hi Dave,

I've had this for quite a few years. Use it both at work and at home, it's had a few new tips as it gets quite a lot of use. I used it a few weeks ago to solder 10AWG into 150A connectors, no problem

I seem to think Maplins stock these.

Cheers

Mark

[Keith Sharples]

I was in much the same boat and decided to get a Maplin soldering station Link. it was well worth the money and does all that I want it to.

Edited By Keith Sharples on 07/11/2017 21:40:19

[john stones 1 - Moderator]

100w, maplins

[Mark Kettle 1]

 

150W electric makes soldering connectors really easy.. 

Edited By Mark Kettle 1 on 07/11/2017 21:48:26

Edited By Mark Kettle 1 on 07/11/2017 21:49:27

[Martin McIntosh]

MAD Dave, a Maplins one is very good. PM me your email if you want a copy of an article I did for a club newsletter on the subject.

[onetenor]

I use a soldering gun bought as part of a kit from I think Netto. Also has 60 w iron helping hand / magnifying glass flux and solder  Also a desoldering pump  Handles 14 SWG piano-wire .but not tried thicker but feel it would silver solder small stuff with care. Aldi and Lidl sometimes have them. I also have a couple of mini  gas torches but need care in handling near models.

Edited By onetenor on 07/11/2017 22:07:40

Edited By onetenor on 07/11/2017 22:10:40

[Geoff S]

I use a 60 watt temperature controlled iron I bought on eBay IIRC. It's a Precision Gold. You can preset the temperature quite easily and the bits are interchangeable from tiny points to ones suitable for soldering battery or esc connectors. I replaced the connectors on a 3700 mAH 4S LiPo this morning with no real problems. For really heavy soldering I use the 125 watt Henley Solon I've had since I was teenager in the 1950s and it's still going strong albeit the bit is getting pretty well-worn.

Just make sure the joint is hot enough to melt the solder without its touching the iron ie it's all at the correct temperature - about 400 deg C.

Geoff

[Focae]

Also, forget lead free solder....it really doesn't make good joints. It is getting harder to find but the best is rosin cored 60/40 solder (60% Lead, 40% tin). I know that the health and safety conscious will shudder at the thought of using lead but I am afraid lead is what makes solder bond to the wire.

For heavy duty wires, 80 Watts is good. I can manage with 50W but the wire wants to suck all the heat out of the iron so it is much harder to avoid dry joints.

[MAD Dave]

Thank you everybody for your recommendations, looks like consensus is ~60W minimum; correct me if you disagree though please.

[Mike Stevens]

Use some flux as make the solder flow much more easily - phosphoric acid. Carrs do a complete range.

[Trevor Crook]

I get on fine with a cheap 60W iron from CPC Farnell. It came with a bit that has an iron coated tip, which means it should have a long life. CPC Farnell also sell leaded solder. It should be fine if you don't eat it.

[Peter Miller]

I use a Weller 40 watt iron and that will solder two bound together 8 SWG piano wire legs, If it won't solder connectcors to a wire there is something wrong somewhere.

Are you using lead tin solder, not the lead free rubbish?

[MAD Dave]

I'm with you Peter, there is only one type of solder!

[gangster]

Certainly agree with the lead free comments. Not sure it's simply a case of the quoted power of the iron. A decent size but well tinned to retain and transfer the heat. I have an old 25 watt antex which is more than adequate for 5mm connectors. By the way I hate the word wattage I don't think it's a real word I don't think it has any technical meaning

[Allan Bennett]

My iron for all my electrical jobs, including heavy power cables to connectors and to each other, is an Antex 50W one (I think -- the label's worn off). The most important thing though is to use a large enough bit; I use a 6mm one for this kind of work, but replace it with anything down to 0.12mm for more delicate work. Antex ones are push-on, so changing is simple.

[Simon Chaddock]

I agree its not so much the power of the iron but the size of the bit.

To solder thick copper wire you need a lot of heat to transfer fast. The more hot copper you bring to the joint the better and because the whole joint heats up so fast its all over quickly with less heat damage.

The copper is this bit is 30 mm wide, 15 mm thick and 60 mm long.

Even with 125W it takes time to heat up but you can solder almost anything.

[Geoff S]

That's a fine soldering iron, Simon, it looks much like my old Henley Solon, but it's a bit tricky to use to solder surface mount ICs

As everyone has said - lead free solder is an oxymoron. 60/40 lead/tin cored solder is the only one worth using. I'm not quite sure why it's criticised by H&S in the quantities and the areas where we would use it (soldering water pipes is a different matter). A former colleague of mine habitually held a length of solder in his mouth whilst working and he was only slightly insane

And on temperature: it's not so much how hot but how much thermal capacity the iron has (ie how long it holds it's temeperature). Simon's iron does it by just being a big lump of electrically heated copper; a 60 watt temperature controlled iron does it by using it's power to maintain the set temperature - often a simple 25 watt iron will cope with small jobs but the more powerful temperature controlled job is much more adaptable.

Geoff

[Martin Harris - Moderator]

Each time this subject comes up, someone usually declares that the instant heat guns are useless for soldering large connectors as they don't have sufficient heat capacity. Maybe they've changed since I had one as a Christmas present 48 years ago (Weller - and it's still going strong!) but mine will happily solder 10 AWG cable to 5mm connectors - and probably much larger. As far as I can see, pumping 140 Watts or so into the tip is more than equivalent to heating a blob of copper remotely with an element until it's been heated to soldering temperature while radiating much of it back into the air...

 

Just for clarification, the demo above isn't my normal technique but I just set it up to show how there is more than sufficient heat transfer to melt and flow solder applied to anywhere on the connector and wire.

Edited By Martin Harris on 08/11/2017 13:19:37

[Gordon Tarling]

My recommendation would be for an 80 to 100 Watt iron that's temperature controlled. I use the Weller one - it's a bit pricey, but it's excellent for soldering many sizes and types of connector. A touch of rosin based flux on the joint will also help a lot, but whatever you do, don't use phosphoric acid anywhere near electrical connections.