Soldering iron size

[Don Fry]

i need to solder some 4 mm wire to a XT 90 plug. My biggest iron a pistol type Weller is not up to the job.

What size iron does this, i.e. How many watts.

[ken anderson.]

hello don, I use an 80 watt job bought from the now defunct BRC hobbies....seems to do the job ok..

ken anderson...ne..1.... solder dept.

[Peter Miller]

I have a Weller 40 iron. Seem to do the job easily/ I also use it for two pieces of 8 SWG piano wire bound together with fine wire.

[Former Member]

[This posting has been removed]

[Don Fry]

So you are saying, I need a heavy tip, to act a a heat sink/source. My wellor is, a 920. Can you het heavy tips for these. I remember as a child, by dad built an iron, and the business end was a piece of copper about an inch in diameter. Took 20 minutes to heat, but soldered things.

[Steve Hargreaves - Moderator]

The main thing you need Don is a decent sized tip to "store" the heat. Those pistol type irons heat up quick because they have such a small tip.....guess what? ...they cool down just as quickly when applied to the job meaning the solder won't melt & flow properly. A large tip will retain it's temperature when applied to the work.

The trick is to get the parts to be soldered up to temperature as quickly as possible so the job can be completed quickly & the heat source removed before the plastic connector body melts.....a good tip when soldering connectors is to have the mating half fitted during soldering then, if the connector body does melt slightly the mating half will hold the contacts in place as the job cools & the plastic solidifies.

Personally I use a 60 watt iron for all my soldering although something a little bigger would probably be necessary for XT90s or similar....make sure to keep the tip clean & well tinned with solder to allow the heat to flow rapidly into the joint.

Another tip is to try & find some low melting point solder....not only does this melt at a lower temperature (who knew?) it also transitions from liquid to solid without that semi-liquid "pasty" stage that ordinary solder often has; this will help you avoid "dry" joints.....LMP solder is not cheap however...

[John Lee]

I find Antex/Weller 40 watt for XT60's, 80 watt for XT90's/EC5's does the job just fine.

I'd also recommend using one of the dedicated jigs & to plug in a blank opposite male/female whilst soldering to prevent any distortion.

[Piers Bowlan]

I use a 'Goot' 20-200W pistol soldering iron that I have used to good effect for some years. I plug a male and female XT60 or 90 together and hold them in a small vice whilst I tin the wires and the plug to be soldered. I press and hold the trigger for about twenty seconds so that it is really hot, then push the tinned wire into the socket in the plug and apply the iron. I hold the iron so that it is touching both the wire and gold socket simultaneously. After a couple of seconds the solder is molten and I push the wire fully home into the socket, which I have half filled with solder when I tinned it. I grip the wire with thin nosed pliers to do this. The problem with heavier gauge wire is that it wicks the heat away even faster which, as others have said, requires a large soldering bit as a heat source. It is also as much about technique as it is about the iron you are using. One last thing, don't use lead free solder.

Edited By Piers Bowlan on 28/05/2018 03:05:34

[Don Fry]

Thank you, I know where I am going now.

[Former Member]

[This posting has been removed]

[Ron Gray]

@KenA - I thought BRC Hobbies were still trading?

[ken anderson.]

hello Ron...unfortunately not as far as i'm aware its now part of robotbirds.....it used to have a shop up here in ne...1.land-its now gone also...so it may exist in name only...RIP....

 

ken anderson...ne...1.... come back BRC dept.

 

check out here...............

Edited By ken anderson. on 28/05/2018 09:56:48

[Martin Harris - Moderator]

Posted by Steve J on 28/05/2018 08:27:43:

Posted by Piers Bowlan on 28/05/2018 03:00:36:

One last thing, don't use lead free solder.

There is nothing wrong with lead free solder.

Steve

Interesting statement - why are such users as aerospace, military, medical and other safety critical applications allowed to claim exemption from requirements to use lead-free solder? My understanding is that lead-free solder is prone to growing single crystal tin whiskers and degrading - have there been developments since the widescale adoption of lead-free solder which was, I understand, imposed purely on environmental grounds.

While I'm here, I have to say that my Weller pistol iron (which I have almost 50 years of experience with) punches well above the weight of its tip - the constant heat replacement seems to compensate for its lack of mass and it has soldered any connectors and large conductors I've thrown it at - although I haven't tried it with XT90s. I wonder if my old iron is a much higher wattage than modern ones - any data plates are long faded away but it pulls 0.75A so that would put it around 180W.

For any soldering outside the capabilities of any normal electric iron (such as NiCd batteries in series in the olden days) I have an old fashioned "lump of copper on a stick" iron which I apply a blowtorch to.

Edited By Martin Harris on 28/05/2018 11:13:57

[Former Member]

[This posting has been removed]

[Martin Harris - Moderator]

But why use an inferior product on your pride and joy? Leaving aside any argument that a failure could result in endangering a bystander should a control system be affected, losing a model for the sake of using lead-free solder (higher risk of a poor joint and deterioration in service) in my view, far outweighs any tiny effect there might be on the environment.

[MaL]

Yes Martin...and I for one agree with you....but you will now need to find a source of lead free solder..... unless you stocked up before the enviromentalists decided you could not be trusted with your own health.

[Peter Miller]

4Max advise cuttiing off the pretinned ends of the wires and using lead/tin solder. to solder the connectors on

You can buy it from Squires quite easily.

I do remember that Hassleblad said that they would have to stop building cameras due to the rules on lead free solder. Maybe they got an exemption too

[Don Fry]

Am I being a bit thick, but most of the electrical stuff on sale seems to be the 60/40 Pb/Sn I have always used.

I have also ordered a heavy 100 watt chisel tip iron.

[Martin Harris - Moderator]

As far as I'm aware, there is little difficulty getting hold of proper solder - the bans are for its use in producing new equipment and there is still plenty of demand. All the mainstream electronics suppliers maintain stocks.

[Martin McIntosh]

As a former professional solderer the best advice I can give is to forget those single temperature irons such as Weller and Antex and buy a soldering station which if you shop around will cost little more. You may still be able to get one from Maplins or try CPC. I think that Aldi have one on sale at the moment too.

These maintain the tip temperature at a setting fixed by you, no matter what you are trying to solder. The one I currently use will easily solder together two 6swg piano wires with only a 4mm tip.

Oh, and don`t be tempted to try lead free solder, it is worse than useless. Even we, legally or not, refused to use it. It really is nasty stuff and I doubt that soldering a few connectors will kill off the planet.

OP, PM me if you want more info.

[Jon Laughton]

Hi Martin is there a specific solderstation you would recommend?

Jon

[Martin McIntosh]

Hi again Jon,

When I worked we just used ones from CPC for which we bought a range of very cheap bits for the various jobs. Part numbers would be meaningless now because things change but the cheapest variable temp. digital ones from the above are quite adequate and have a very long life.

I also have the best of the best which is Metcal which I used in a previous job but I am afraid that these are £250+. Got mine for a quid! (company closed down).

[Jon Laughton]

Hi Martin - looks like you got a bargain! Thanks anyway

[Piers Bowlan]

I bought a cheap soldering station, I can't remember the brand and it is packed away right now (house move!). It looked the biz with a nice digital readout, however I found it was not up to the job and I reverted to my 'goot' pistol iron, for plugs and connectors. I suspect that buying a good brand and paying more is the answer.

[Nigel R]

Technique helps.

But a nice big iron does wonders and covers many sins in the technique department.

Or a fancy temperature controlled one, as Martin says, they are the business.