Soldering

[4472]

I am about to dip my toe in the water. I know the theory of soldering but would like opinions on the best/cheapest solder to buy. Would it be best to buy self fluxing or separate solder and flux

Mod Note. Topic moved to a more suitable forum area.

[Bufferstop]

There's not a lot to it really
Iron 25watt with changeable tips. Or use a temperature controlled solder station.
Solder, use flux cored 60/40 lead/alloy solder. You may have to get this online as most retail outlets either won't stock it or tell you it's illegal, which it isn't. The alternative lead free is far more difficult to use and doesn't do such a good job.
Keep the iron clean and tinned with the solder then apply solder to the items to be joined, bring them together and touch the joint with the iron with a little more solder, until it all runs together, then hold the joint steady until it cools. Best bet is to watch someone do it, you-tube or demo at an exhibition.

[Ex-Pat]

Halfords still do the "proper" stuff:

https://www.halfords.com/workshop-tools ... -wire-100g

Special low-melt solders (not from Halfords) are also available for white metal kits etc..

Would also recommend the use of a carbon-fibre pen for cleaning the metal in advance.

[b308]

Depends what you are soldering, so that's the first question I'd ask...

If it was brass kits for 4mm scale or below low melt solder and liquid flux and a 18w iron will suffice. TBH that's the only iron I use, for constructing handbuilt track and wiring as well as the brass kits, I've never had the need to use anything larger.

But I have no doubt the experts will tell me that I am wrong and must have at least a 25w iron!

BTW get a decent iron, not a cheapo one, I would recommend Antex.

[4472]

I will be soldering wire to track and brass

[Dad-1]

One thing not mentioned is don't be impatient, don't try to start before your soldering iron is
fully up to temperature which is one of the learner mistakes.
Also make certain joining surfaces are freshly cleaned to remove surface oxides. No good lightly
filing under the track then leave until tomorrow before you solder, the fresher the better.

Geoff T.

[Mountain]

I have more then one soldering iron. One is a cheap temperature controlled solder station which says it is up to 50W but it doesn't seem as powerful as that, and this is the one I use the most as it has a handy stand for the soldering iron. (Regarding stands. Most stands I find the base is far to light so one may need to clamp or screw them down. Having a stand means you are less likely to burn yourself by accident).
I also have a resistance soldering iron (Gun type) which was rated as 100W but yet again was more like a 25W. It heats up in seconds and I used it for years until one day I was soldering track and its plastic got a bit hot and the metal resistance bits started to move. I pushed them back and the plastic hardened around them when it cooled. It seems unaffected but I've not used it since as most of my soldering was in making track so a powerful iron is better.
My third iron I've not actually used yet. It is a nice 40W iron.
25W iron is fine for electrical work, but if one wants to make things like track with PCB sleepers, or solder tin etc then a more powerful iron is better as one is not spending ages waiting for the parts to heat up sufficiently before the solder will melt onto them.
On the other end of the scale, if one is soldering something like white metal then one needs a less powerful iron as a powerful one would likely melt the white metal before the solder has a chance to take. I've not tried soldering white metal, but my temperature controlled iron turned right down would be the one I'd use, and is best to use low melt solder.
I'm no expert though. More like a long term amature. I hope to start soldering tin one of these days. That's a future project. To experiment with tin a bit more for scratchbuilding. So far my tin work has been cutting and folding as tin retains its shape if tucked in etc. I bought the 40W iron ready for this use in mind.

[Mountain]

To simplify regarding 25W or less or40W or more irons. It all depends on the type of things you need to solder. Electrical contacts a 25W iron is fine. White metal melts easily so a temperature controlled or a low powered soldering iron is the one to get. Brass. Depends on the thickness I guess. Either a 25W or a 40W. I'd prefer a 40, but if most of your soldering will be electrical orientated a 25W will do. Just takes longer to heat up the part before the solder melts.
Tin needs at least 35W or over. One needs a more powerful iron to get the tin hot enough for the solder to take.

Regarding solder. If you can get one with lead and flux in it, but also buy seperate flux as often the solder doesn't have enough flux for the part one is soldering. Take care when using flux as it is a corrosive material. You will most likely need a little extra flux if soldering brass. The flux helps the solder to flow. Without flux you end up just heating a hot blob of solder which doesn't want to take to the material you want it to bond to. Also regarding that, the metals being soldered need to be cleaned up. A simple rub with an abrasive material will do. I've even used a track cleaning rubber (When I didnt have anything else at hand) but the smell of melting rubber resedue wasn't nice, so maybe that wasn't such a good idea!

[Admin4]

I will be honest, i hated soldering (and still do ) but it does just take practise to get a handle on it, my latest layout has been done by soldering dropper wires onto the track rather then buying pre soldered fish plates and I am now more comfortable with it & have saved cash so a win win.

My 'process' may not be ideal but i find this works for me:
0) put soldering iron on to max (i have a temperature controlled one but prefer max)

1) 'dry fit' the track to make sure its going to fit / help figure out where the track needs dropper wires.

2) decide on location of dropper wires, if using set track i tend to go for the gaps already in place:



If using Peco flexitrack i use a knife to carefully cut a gap between the sleepers to give me the above space to work with - a sharp scalpel is idea as it gives accurate clean cuts so you dont cut off more then you need to. I also use the scalpel to scrape the surface of the rail to clean it / remove top layer of dirt that will stop solder from sticking to it

3)I check the orientation of the wire and cut two lengths to size (ill be honest here i just cut a long bit that i can trim later on under the baseboards ) my plan which you can see in the above photos is blue=black=back which means i can use blue or black feeder wire but its always on the rail that ends up at the back of the layout

4) strip the end of the wire i am going to attach to the rail & twist the wire strands together (i leave the other end as is because i find it easier to feed through the baseboard that way)

5) put flux on the exposed wire

6) use soldering iron to melt some solder onto the iron, bring this briefly against the flux covered wire. this will pull the solder from the iron to replace the flux and cover the end of the wire - this is called tinning

source: http://www.docgreenwoodturner.com/solder2.html

7) i then place a little bit of flux on the rail where i want the wire, i then bend the wire to a right angle & press it against the track with the flux

Using the soldering iron i get more solder on the end and then hold it upto the wire/flux for a second to melt the solder and connect them together

9) hold the wire still, if you watch it you can see when the solder sets as it changes colour ever so slightly - when it does this or after a few seconds i test the join by carefully tugging on the wire - if it comes lose the connection was not good enough and i will clean up and start again.


i have found that having the soldering iron turned up to max means i can get in and out quickly, i found that using lower temperatures means that i needed to have the iron in place longer which heated up the rail and melted sleepers you will know when you do this as it stinks!

Another tip is to come in at right angles to the sleepers to reduce chances of catching the sleepers on the iron itself and melting them, you will also need four pairs of hands to keep on top of it! but little things help, like buying solder on a reel so that you can leave it sticking out so you can simply press the iron against it to get more solder.

I had a needle point tip for my iron and assumed this would be best for this type of work, but in reality its the smaller standard bit that works best as it can hold more heat & effectively transfer that to what your working on quickly.

The best advise however is to practise, experiment and see what works for you - it will get better & is such a useful skill to have in this hobby its well worth the time figuring it all out.

I hope this helps, good luck & let us know how you get on - especially if you find out any good tips we can use as well

[b308]

I will be soldering wire to track and brass

A 25w is quite sufficient for soldering wire to rails unless you are using G scale track. Even a cheapo 25w (pah! spit!!) will do the job.

As for Brass, as I mentioned earlier it depends on the brass thickness. For soldering smaller scale kits (OO scale or below) an 18w or 25w will suffice. For O scale and above you might be better looking at other alternatives such as blow torch, etc. as you will probably be soldering thick chassis bars together.

With soldering it's all about getting sufficient heat in the right place, so using a large iron could result in too much heat and other fittings on the kit falling off whilst you solder another on! There's a chap called Allen Doherty who is a manufacturer or "scratch-aid" brass kits (i.e. the basics but not a complete kits) called Worsley Works. He attends many shows through the year and gives free advice and tutorship on soldering at the shows he attends. I'd suggest you check out the shows he's going to and sit down and have a chat with him at one of them, he's a really nice bloke.

http://www.worsleyworks.co.uk/

Mountain, you might want to take a look, he does O scale NG kits as well!

[TimberSurf]

I wrote this for just this sort of question Soldering Guide

Re original post, definataly resin cored solder and not "Lead free"
Additional flux is always good, but get the non corrosive type (unless you are building brass engines)

[Bufferstop]

@b308
I'd say for you an 18w iron would be right for the size of your models. I think you might notice it being a bit underpowered if you were trying to solder droppers to code 100 rail. It's all down to the transfer of heat, small section rail has a lower thermal capacity than the larger code 100, so soldering a joint absorbs less calories per second and your 18watt iron recovers quickly. The heavier rail section can absorb heat faster and you'll notice the iron cooling, so a somewhat chunkier 25 watt has more capaciity and can deliver enough heat to make the joint flow, before it starts to cool noticeably.

[Mike Parkes]

The design of the soldering iron can be factor with Antex irons outperforming Weller irons in my experience of equivalent wattage - the reason was something I learnt at school - the bit on an Antex iron fits round the heated shaft so all the heat has to pass into the metal of the bit whereas on the Weller iron the bit fits inside the heated shaft so that a lot of the heat simply evaporates away without heating the bit. I have both 18W and 25W Antex irons and the 18W usually suffices for jobs where I have read users of Weller (or equivalent) type irons insisting that a 25W iron, or greater, is needed.

[b308]

All my track is code 80 or below, John, though I have seen the Antex used for code 100. I did play safe by mentioning using a 25w for track in that last post, though!

[Bigglesof266]

I have been hobby soldering in an amateur capacity now intermittantly as required for nigh on 50 years. Have all the tools, from solder suckers and soldering station offering a variety of tips through 80W Weller iron. I am generally competent with them comfortably soldering everything from a scratch built control-line vintage tin tank, through R/C Deans connectors onto LiPo battery terminals and bullet connections on motors and controllers etc., and neatly so you'd think it a factory bot job. Even circuit board SMT components I can tackle without making a balls up of it most of the time.

But, I have to say, the singular soldering job I utterly detest is soldering droppers to track.

Why? Doing it consistently without melting some of those %#@£^! fragile plastic chairs securing the sleepers to the rail at least some of the time eludes me. Tried using heat sinks, but it still occurs, too often percentile wise for my liking. I find it difficult.

If someone here truthfully has a 100% success rate with this task soldering tinned droppers to nickel silver PECO Streamline track without ever melting a chair, I would sincerely love you, nay humbly beseech you to share your 'magic' (respect) technique with me/us.