Dread of soldering

[The Johnster]

I've never been good at soldering.  Please, guys, I know everything you're going to say, so can we just accept that Johnster and soldering don't mix and get on with our lives.  Dry joints, heat all over the place where it shouldn't be, dirty great blobs tripping up the trains, the usual stuff.

 

Today, bought a 40 watt iron from Maplin's, in a box kit with stand, solder wire, and a desoldering suction pump, in an attempt to resuscitate a dead chassis with a broken connection from the pickup on one side.  Bad news first, failed to resuscitate the patient, life declared extinct half an hour ago.  Good news, my solder joints are fine and the problem with the chassis is elsewhere; I may have hamfistedly shorted out the capacitor!  At least I am no worse off than I was at the start of the evening; it didn't run then and it doesn't run now either.  So, emboldened by my success, I went on to properly solder all the electrical feeds on the layout, which has gone well.  Perhaps I am overcoming a lifelong fear!  If a chip-fingered fat boy with shaky hands and failing eyesight like me can do it, there's hope for everyone!!!

 

The kit was £9.99 and I am delighted with it.  My old iron was 25 watts and the extra power makes a big difference

[Guest 40-something]

I used to be terrible at soldering, now Im just not very good.  I agree with Dutch Master that a proper tool is half the job done, without a doubt.

 

Im much more confident at soldering wiring etc but not confident that I could tackle a brass kit

 

Practice is key though

Edited May 18, 2017 by 40-something

[brossard]

Yep, practice is the key to soldering kits.  IMO, being able to work in brass opens up a new universe of modelling possibilities.  Having the right kit is very important.  In addition to the iron, the appropriate solder and flux for the job are crucial in order to make soldering pleasant.

 

John

[Junctionmad]

People , in my view , buy irons with too little power. The power is needed to improve the " recovery" time and to allow the iron to handle metals carrying away the heat as opposed to circuit board soldering , where small power irons are acceptable

 

40 w minimum , 50 to 60w is good too

[Oldddudders]

I'm with the OP. I know the ingredients, but the cake doesn't always bake very well. Last night I finally got round to re-soldering an iffy connection. It is on the further side of the rail, and an adjoining backscene means I couldn't really see quite what was going on. Lashings of flux paste on the site and the recalcitrant wire, a drop on the (30 watt, Remploy) iron tip, but it took several goes to get it all to happen, and a couple of (Code 83) sleepers don't now look quite as Peco intended. The track has been in situ for a decade, but never painted.

 

Since I have quite a lot of track, DCC, and have droppers from every rail, I suppose my soldering isn't too bad. But nor is it utterly repeatable, which it would certainly need to be to undertake a brass kit. That remains a step too far.

[Guest]

I think to get better at something, you have to want to get better at something. Soldering, to me, is a neccesary evil. I can solder copperclad at baseboard joins and add droppers but that's where my skill level and my interest ends. I have a "that'll do" attitude to soldering. The iron and I tolerate each other at best.

[Enterprisingwestern]

I think to get better at something, you have to want to get better at something. Soldering, to me, is a neccesary evil. I can solder copperclad at baseboard joins and add droppers but that's where my skill level and my interest ends. I have a "that'll do" attitude to soldering. The iron and I tolerate each other at best.

 

Aha, a future Spanish student!

 

Mike.

[Guest]

Aha, a future Spanish student!

 

¿No entiendo? El hierro de soldar es caliente. Eso es todo lo que sé.

 

I'm moving onto Lesson 2 "At the shops" next.

[Enterprisingwestern]

Leccion uno.

No recoja el soldador en el extremo caliente.

 

Mike.

[Junctionmad]

I think to get better at something, you have to want to get better at something. Soldering, to me, is a neccesary evil. I can solder copperclad at baseboard joins and add droppers but that's where my skill level and my interest ends. I have a "that'll do" attitude to soldering. The iron and I tolerate each other at best.

 

My first practical lab in college as a budding EE , the lecturer handed everyone 500 resistors and a pile of scrap pcbs and said away you go, fit and solder everyone

 

Trial by fire !!!

[The Johnster]

Many thanks for the responses, everyone, and especially the 'friendly/supportives'.  To keep perspective, a failed attempt at resuscitating a dead chassis that was not let down by the soldering, and 4 connections on a tiny blt, are not world changing events, even in my small world.  I have to agree that a better tool has eased the terror of the job; not only is the new iron a 40 watt compared to my old 25 watt one, but it has a finer tip, a point rather than a sort of bevelled cylinder.  I think that this has concentrated the heat into a smaller area much more effectively, and resulted in the solder melting and the iron being able to be taken away before conduction has had much chance to do harm to the surrounding track/chassis block/whatever else it is, or my hands start shaking and everything ends up where it shouldn't.

 

Like 40something, I am a bit more confident about the whole thing now, but would be wary of tacking a brass kit, especially something as complex as a loco.  I am on the lookout for auto trailers not covered by the rtr offerings, though, and with a little more practice kit building in brass become an option, and after than I could think about replacement chassis!

 

Steady on, now, Johnster my boy, walk before you try to run...

Edited May 19, 2017 by The Johnster

[LongRail]

Key to soldering is clean areas first and ensure item to be soldered is heated before applying the solder blobs are created by trying to heat solder directly with iron onto the cold metal. If you employ a good flux it will help transfer the heat to the item.

Like all things patience and practice will allow you to master the technique.

 

Once you are confident and have the basics you will be able to use a lower wattage iron.

[Waverley West]

The light-bulb moment for me was discovering flux. Up until then, soldering had been very hit and miss for me.

 

It seems obvious looking back now.

[grahame]

Yep, I have a love hate relationship with soldering.

 

And it doesn't seem to be dependant on practice. I've certainly soldered and practiced quite a bit (but not brass kits) over many years but still I can have sessions where all the joints are perfectly soldered and finished, and at other times it'll be a mare with blobs, mess, burnt fingers and poor joints. And I was taught at school in metal work classes.

 

Nowadays I grit my teeth at the thought of soldering, then pluck up courage and try to get the session over and done with although the results can be unpredictable.

 

G.

Edited May 19, 2017 by grahame

[The Johnster]

Looks like I am much less alone in this than I thought! 

[Tricky Dicky]

Whilst I have sympathy for those who struggle to solder which is mainly due to poor technique and or lack of understanding, I take issue with those that make it out as a Black Art where you have to sell your soul to the devil or mutter the right incantations whilst soldering.

 

No matter whether you are Brazing, Silver Soldering or Soft soldering we do as modellers the principle is the same, the two metals to be joined need to be brought up to the temperature at the joint at which the solder will melt only then will fusion of solder to metal take place. Focussing on soft soldering, a soldering iron is just a heat source just like the plumbers torch and like a torch will easily melt solder but unless you get the joint up to solder melting temperature all you are doing is creating blobs of solder on the surface with little or no adhesion.

 

Cleanliness and keeping the join clean is another important issue. If the metals you are joining look dirty or tarnished then clean the join area a fibre glass pen for light contamination abrasives or files for more severe. Keeping the area clean during soldering is what flux is for. Heat a piece of steel in a flame and round about 250C + you will see colours appearing on the surface ranging from straw to purple in colour and eventually going black as the temperature increases, these are oxides forming and will prevent solder fusing. Most fluxes, Rosin as in multi core solder tend to prevent the oxides from adhering to the metal by suspending them in the flux. Plumbers these days favour self cleaning fluxes as it saves them time cleaning pipes and fittings, many of these contain acids that need to be flushed away so not a good idea to use on electrical work.

 

As for soldering technique e.g. soldering a through hole component to a PCB. First, make sure your iron tip has a coating of solder, referred to as tinning, if not clean/wipe the tip and run a little solder on till it is a shiny silver colour- do not put a blob on. Second apply the tip to the join and hold, do not move it about trying to paste the solder, count 1-2-3 and add the solder it should flow on contact once sufficient has flowed remove the solder then the iron. Once the solder freezes it can be moved, a good join will not form a blob but should look like a miniature volcano round the wire. It is bad technique to melt a blob of solder on the end of the tip and then transport it to the join and attempt to paste it on. Whilst your melting and moving the iron in position you are burning away the one thing helping you solder namely the flux and pasting with the iron is not helping to heat the join.

 

As for different wattages of irons, again a lot of misunderstanding exists. When you place an iron on a join heat transfers from the tip into the join, that heat needs to be replaced by the element a higher wattage iron can do that quicker hence why on larger joins where the heat sinking factor is greater a high wattage iron is used whilst on most electronic work heat sinking is less of an issue and so less powerful irons can be used. Johnster has perfectly summed up his success with soldering wires to rails.

 

Many thanks for the responses, everyone, and especially the 'friendly/supportives'.  To keep perspective, a failed attempt at resuscitating a dead chassis that was not let down by the soldering, and 4 connections on a tiny blt, are not world changing events, even in my small world.  I have to agree that a better tool has eased the terror of the job; not only is the new iron a 40 watt compared to my old 25 watt one, but it has a finer tip, a point rather than a sort of bevelled cylinder.  I think that this has concentrated the heat into a smaller area much more effectively, and resulted in the solder melting and the iron being able to be taken away before conduction has had much chance to do harm to the surrounding track/chassis block/whatever else it is, or my hands start shaking and everything ends up where it shouldn't.

 

Like 40something, I am a bit more confident about the whole thing now, but would be wary of tacking a brass kit, especially something as complex as a loco.  I am on the lookout for auto trailers not covered by the rtr offerings, though, and with a little more practice kit building in brass become an option, and after than I could think about replacement chassis!

 

Steady on, now, Johnster my boy, walk before you try to run...

Many will say using a high wattage iron in the circumstances above leads to melting sleepers, well the truth is it is the opposite. Because a low wattage iron will struggle to replenish the heat into the tip you end up holding it on longer allowing the heat to spread along the rail eventually it reaches sleeper melting temp. A high wattage iron will deliver the required heat quicker, remember 1-2-3, thus localising the heat and making the whole process quicker. Because you are localising the heat it will then dissipate harmlessly into the cooler metal either side of the join. Another misconception is that high wattage irons are hotter than lower watt types, again a fixed temp 18W iron will achieve the same temp. as a fixed temp. 50W iron. Some variable temp. irons do use varying power input to maintain different temps. but that is the only time heat and wattage are related. Finally, as this has now become an epistle, heat transfer into a joint is determined by the size and profile of the tip, so with a suitably fine tip a high wattage iron can used for small electronic soldering however from the users point of view it is probably more comfortable to manipulate a smaller and therefore less wattage iron in these circumstances.

 

I apologise if much of the above may sound pedantic, but over my lifetime I have much experience of soldering ranging from brazing with oxy-acetylene to silver soldering precious metals with hall marked solders and in my latter years an awful amount of electronics.

 

Richard

[Dava]

I'm no better than anyone else with soldering and agree with most of the points above. Also,

 

- Nickel silver is in my experience a bit easier/nicer to work with than brass when it comes to loco and other kits

 

- Solder paint is useful, I got a jar from Eileen's Emporium. Mix then paint [i use cocktail stick] it on for those 'invisible' joints. It's not the strongest join but it is neat and reliable. Even soldering whitemetal to brass I'll tin the brass with it first then use low-melt solder. Practice on those lovely Severn Models kits which don't need soldering anyway

 

- I use Weller 25 & 40 watt irons with a 12 volt one for whitemetal , the Weller ones do burn through bits though. I'll buy a temp-controlled soldering station when I see one I like at good VFM.

 

- Lead-free solder is useless.

 

Dava

[Enterprisingwestern]

 

- Lead-free solder is useless.

 

Dava

 Never a truer word said, hard enough work in plumbing, I wouldn't even like to think of using it in a modelling context.

 

Mike.

[RAF96]

One of our test jobs in brats training was to solder together the eiffel tower using bits of wire and various melting point solders.

 

Object of the excercise was to plan the task so as to get the individual bits together into parts then assemble these parts together into a whole.

 

Hence bits were soldered together with higher melting point solder to make parts and parts were soldered together with lower melting point solder to make the whole tower.

 

If you got it wrong then it self dismantled so you could start again.

 

Soldering is simply the use of good tools, selecting proper consumables for the task, adopting good methodology and plenty of practice.

[Guy Rixon]

Nickel silver is in my experience a bit easier/nicer to work with than brass when it comes to loco and other kits [...] Lead-free solder is useless.

 

 

Nickel silver is definitely easier. Ordinary brass quickly forms mucky oxides and these stop the solder from bonding. I've had cases where the joint mucked up before the solder melted! Nickel silver is less prone to this.

 

Using the right flux helps. Years ago, I started building stock in 2FS where the wagon chassis are usually etched in nickel silver. I used cored solder and Carr's Red flux as that was all I had available. For the NS, this turned out to work really well. Later, I moved back to brass kits in 4mm scale and found that the same solder/flux combination was a bit pants. For ordinary brass, I think one needs a stronger flux. Carr's green works well for me.

 

One of the problems with lead-free solder is that the replacements for 145-degree solder melt at a higher temperature and the leaded version and are not so good at filling gaps. If one gets a close fit in the metal to be joined then it works; if one tried to bodge it across gap then it won't play.

[The Johnster]

Noted.  Bodging across a gap sounds like the sort of thing I'd do...

[RAF96]

Soldering 101:

1. surfaces to be soldered must be squeaky clean, I find a fibreglass pencil is as good as anything for the task.

2. use resin cored real solder - it works for 99% of my soldering jobs. Solder paste for hot air gun work and smd soldering.

3. if 2. doesnt work use separate flux, either liquid or paste. This will help solder flow whilst protecting against oxidisation of the joint.

4. use a solder which is suited to the task - there are many varieties. I got several boxes from Lidl for various uses but generally use the everlasting reel of 3-core solder I pinched from 'stores' 40 years ago.

5. use an iron which will heat the job adequately. Too big an iron can melt sleepers, damage electronic components, too small an iron will never make a decent joint.

6. apply solder to the iron and it will flow into the joint when it is ready.

7. practice joining any old bits of pcb, wire, rails, etc together until you get the hang of if.

Summary - clean, heat, apply solder, watch for flow, remove iron and admire the result.

 

Which iron do I use...

I have a hefty Weller gun for soldering droppers to rails, a battery operated highlighter sized iron for soldering to decoders, a hot air gun for soldering smds to pcb and an Antex 15W general purpose iron for everything else. In the toolbox - One for the old guys - I have an ancient Mox soldering iron but no fuel pellets unfortunately.

[Crosland]

- Lead-free solder is useless.

 

 

Again, it's all down to experience and having the correct tools.

 

Given the above, there is absolutely no problem with lead free solder.

[NinOz]

Again, it's all down to experience and having the correct tools.

 

Given the above, there is absolutely no problem with lead free solder.

Well I wouldn't say no problem for me.

Lead free has a different "feel" to it in the way it melts and flows which made my attempts to try it a bit unsatisfactory; particularly with fine decoder wires.

But as you say "experience".  I am sure with a bit of perseverance I could get the feel and wonder why I was having so much concern.

I think many people just quit in frustration in the early stages of adapting (like me).  Especially if one already has several spools of the lead/tin alloy to hand.

 

CFJ

[newbryford]

5. use an iron which will heat the job adequately. Too big an iron can melt sleepers, damage electronic components, too small an iron will never make a decent joint.

 

 

Depends what you mean by big.

 

Big as in (said in a Jeremy Clarkson style), "more power" is a good thing.

 

I usually use a 50W Weller with 2mm tip for soldering to rail

 

Cheers,

Mick

Edited May 21, 2017 by newbryford