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Soldering Practice

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Soldering Practice
Posted by cowman on Saturday, December 14, 2019 7:11 PM

While waiting for my layout room to materialize in a finished form, I am thinking that doing some soldering practice.  I can sweat copper pipes just fine, but any other solderiing attempts have not gone well.

Wires are copper, so pratice on them should go OK.  My question is mainly for soldering track and feeders.  I have some extra nicklel silver track, but all useable on the layout.  I have sold most of my brass, but do have some steel, which I plan to use for scenic elements, loads, scrap or maintainance yard, if I mess that up, no problem.  Are the soldering characteristics similar between the nickle silver, brass and steel?

Thank you for your help,

Richard

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Posted by RR_Mel on Saturday, December 14, 2019 8:17 PM

Soldering is a piece of cake!  Been soldering since I was 8 years old.  What you are soldering must be clean, no dirt, rust, grease or oil, no paint and of course no insulation.
 
Use the correct soldering paste or flux, NO Acid core or acid flux around electronic stuff.  I keep my soldering iron at 700° to 750°.  Lots of heat and quick in and quick out.  Apply the solder to the joint not the iron.
 
I solder my track feeders to the bottom of the rails between the ties, that way the wires are not seen.
 
 
Mel
 
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
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Posted by doctorwayne on Saturday, December 14, 2019 8:43 PM

cowman
...Are the soldering characteristics similar between the nickle silver, brass and steel?

Nickel silver and brass are pretty similar, but when soldering brass, it helps if you first remove any tarnish - some wet/dry sandpaper (use it dry) will clean it up quickly.

I've not had much luck soldering steel, but don't have much need to do so either.

Wayne

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Posted by Overmod on Saturday, December 14, 2019 9:32 PM

Surfaces to be joined have to be perfectly clean and free of oxide, and mechanically filed and kept aligned so the mechanical joint is between matching surfaces.  Do not think that solder is a gap-filling material like hot glue.

Solder balls up because a surface is dirty.  If you can't touch a sliver in tweezers to a heated joint and watch it 'wick inside', you haven't set up correctly, and you'll either be blobbing it on or producing some flavor of cold joint, neither of which is particularly good.  There are times and places for solder-fillet reinforcement, but not that many...  

Flux not only cleans the surface, it keeps air out of the joint like the flux in submerged-arc welding.  Use it accordingly.  Note that you can make a controlled-atmosphere 'glovebox' using appropriate shielding gas if you want, and solve some of the joint-contamination issues firsthand instead of relying on flux as a kind of kludge

I'm tempted to say you'd do well to get a microplating outfit (does Texas Platers Supply still sell little ones?) and put some appropriate electroplated spot on steel where you want to solder it to ensure a good bond.  You can approximate this with a few chemicals and an appropriate transformer, etc., as the reactions are not that critical (but surface prep, again, is)

There is an alternative to soldering for working with plate and fine wire details: small spot welders.  Watch the YouTube video on fabricating Nixie tubes to see one in action.  This is the only method I'd consider using to make metal handrails or anything else requiring butt joints in fine-section materials, and of course there is no tendency for previous joints to soften if not kept cool with heatsinks or wet sops while the next one is being prepared.

I strongly recommend you get a microflame torch and use it for critical soldering -- it can heat up the relevant area of a joint real fast, before the heat can start diffusing along to other areas. 

Small lasers are an option (as used in some small-electronics 'surgery' for example when wavesoldering isn't an option), but there are a great many caveats, many relating to inadvertent reflections that can cause immediate internal eye burns, that make this a dubious approach for most modelers.  

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Posted by hon30critter on Saturday, December 14, 2019 10:42 PM

Hi Richard,

As Mel said, "soldering is a piece of cake", that is if you do it properly.Smile, Wink & Grin

The first thing to understand is that the surfaces to be soldered together must be clean! If the metal looks clean then soldering flux is usually all that is needed to get the solder to flow where you want it. If the surface is darkened then you may need to use a bit of very fine sandpaper as Wayne suggested. Also as was said, if the solder beads up instead of flowing onto the surface, then the surface(s) are not clean enough.

The second thing to understand is how much heat to use. This can be a bit tricky. Too much heat will melt the wrong things. Too little heat can melt the wrong things too! If your iron is not hot enough then it will take a long time for the solder to melt. During that time the heat can spread to other things and melt them. For example, if you are soldering wires to a toggle switch with a plastic body and you leave the iron in contact with the terminal for too long, you can melt the switch body and ruin the switch. As Mel said, "Lots of heat and quick in and quick out".

To use the track feeder example, if you are using a small pencil tip iron like those designed for electronics, i.e. less than 25 watts, the tip won't have enough heat to get the rail and the wire up to the temperature required to melt the solder for several seconds. During that time the heat will be spreading along the rail and that's when the ties start to melt. If you use a larger iron, the rail and the wire will heat quickly, the solder will melt and flow quickly, and you can remove the iron before the heat has had a chance to travel very far along the rail.

If you want to make the joint go together really quickly, the best thing to do is to 'tin' the surfaces first. That means that you apply a small amount of solder to each to each surface before soldering them together. Apply a tiny amount of flux to the surfaces and then add the solder. That will give you two perfectly clean fresh surfaces to join together and makes soldering a breeze. I strongly recommend doing this!

One other factor is the tip of your soldering iron. It has to be kept clean! I used to do that by dipping the hot tip into my tin of soldering flux, but that destroys the the tips very quickly. The best solution is to use a brass or copper scouring pad designed for the purpose, like this:

https://www.amazon.ca/Atoplee-Soldering-Cleaning-Sponge-Brass/dp/B014OUOXKE/ref=sr_1_1?keywords=brass+soldering+tip+cleaning+pads&qid=1576384729&sr=8-1

Get into the habit of wiping the tip of your iron in the pad before every joint. Your tip should stay clean and shiny. If your tip still won't stay clean after using the sponge there are other issues at work. Some soldering irons are simply pieces of junk, even the name brands. I can recommend a great soldering iron if you are interested.

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by gregc on Sunday, December 15, 2019 4:21 AM

cowman
My question is mainly for soldering track and feeders.

use rosin core solder.  no need for paste.

wait until the iron is hot.   touch the iron with solder and see if it melts.  clean the tip with a wet rag if the tip is not shiny.

strip, bend and tin the feeder.   i put a 90 deg bend in the feeder wire.   heat the wire and let a little bit of solder flow onto the wire

pre-tin the side of the rail.  I sometimes rub the tip back and forth against the rail to create a clean spot.   hold the iron against the rail.   hold the solder against the tip and the rail.  be patient,  let a small amount of solder flow onto the rail.  (blow the smoke/fumes away)  remove solder iron before plastic ties melt (too much).

put down the solder and hold the feeder.  hold the iron against the solder on the rail and hold the bent end of the feeder against the tip and solder.    when the solder melts again, the wire will seat against the rail.  remove the solder iron and hold the feeder in place until the solder cools.

yank on the feeder to make sure its a good joint.  If it pulls off, just reheat and try again.

 

solder is not a glue, it actually allows a chemical bond between the two pieces of metal.   

greg - Philadelphia & Reading / Reading

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Posted by betamax on Sunday, December 15, 2019 6:40 AM

Nickel Silver, being a copper alloy, is easy to solder.

As many have pointed out, the metal needs to be clean, the iron hot.

As to solder, and flux, they have a shelf life.  Most manufacturers of solder will specify a three year shelf life from date of manufacture.  After that point the flux is no longer as effective as it should be.

https://dccwiki.com/Soldering

That container of flux, it has a life of 3 to 5 years from the date of manufacture.

As has been mentioned, and must be mentioned again, do not use Acid Flux.  Rosin flux only for electrical work. Unfortunately, many of the fluxes recommended are acidic. So be sure to read the label and ensure it is rosin flux.

For soldering steel, you will need much more aggressive flux, as well as some aggressive preparation and a hot iron.…

 

 

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Posted by SeeYou190 on Sunday, December 15, 2019 7:16 AM

Lots of good stuff here.

.

As others mentioned, from what I have done, soldering brass and NS are pretty much the same, and easy.

.

I have never been able to solder to steel effectively, so I would say it is much different.

.

-Kevin

.

Living the dream.

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Posted by ROBERT PETRICK on Sunday, December 15, 2019 9:45 AM

In addition to what everyone else has said . . . you can also get copper wire that has been pre-tinned.

Good luck.

Robert 

LINK to SNSR Blog


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Posted by The Milwaukee Road Warrior on Sunday, December 15, 2019 11:36 AM

Glad to see this thread since I have never soldered in my life - ever.  I'm sure its easy once you do it, but I'm a bit hesitant lol.

I'm looking to get the Horizon Hobby 950 iron.  I think its also called DuraTrax on amazon.

https://www.horizonhobby.com/trakpower-tk-950-soldering-station-dtxr0950

My local hobby shop sells this one as well as the 955 with a digital display (the only difference I can see).  I assume either are good for model RR?

Sorry, not trying to hijack this thread...

Andy

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Posted by BigDaddy on Sunday, December 15, 2019 11:47 AM

Randy Rinker has recommended the Xytronic   It's less expensive than yours

https://www.amazon.com/Xytronic-LF-389D-Mini-Type-Digital-Soldering/dp/B00E4WUN8O

Henry

COB Potomac & Northern

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Posted by Overmod on Sunday, December 15, 2019 1:38 PM

Something that shouldn't be forgotten: When you are done soldering, be sure to clean, rinse and agitate/brush the joint area as appropriate to remove any trace of the flux.  

It can be easy in the joyful aftermath of assembling a complex set of parts to forget to do more than just wipe them down.  Passivation and physical removal of the flux is still important.

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Posted by gregc on Sunday, December 15, 2019 2:40 PM

another reason to use rosin core solder.   no cleanup required

greg - Philadelphia & Reading / Reading

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Posted by The Milwaukee Road Warrior on Sunday, December 15, 2019 4:15 PM

gregc

another reason to use rosin core solder.   no cleanup required

 

Can that solder be used with any iron I assume?

Andy

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Posted by gregc on Sunday, December 15, 2019 4:44 PM

yes

greg - Philadelphia & Reading / Reading

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Posted by cowman on Sunday, December 15, 2019 5:14 PM

Thank you all for the information.  Some of it was reminders of things I had once heard, some, I was sort of aware of and some totally new.

It does look like pratice should be either with brass or nickel silver, as I want to melt as few ties as possible.

Now to get the room done, pratice soldering and make a layout to run trains on.

Thanks again for the help,

Richard

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Posted by Overmod on Sunday, December 15, 2019 6:02 PM

gregc
another reason to use rosin core solder.   no cleanup required

The crap in typical rosin-core over-the-counter solder most definitely should be cleaned off (with a good flux cleaner suitable for that purpose).  Cf. this advice (from Electronics Weekly):

Rosin flux is the most aggressive flux and in today’s sensitive electronics it is most likely to harm over time if heated to its activity point, meaning it becomes acid and will start to corrode areas where residues have not been removed after use ... The most important thing to remember is whatever flux you are going to use it is not going to cause any long term problems if you take care to remove any residue, we try even to remove no clean fluxes just to be on the safe side since it’s pretty easy to do with the correct flux removal cleaners.

There are a number of proprietary 'flux cleaners', some of which have an interesting and somewhat expensive chemistry; in my opinion these are overkill for most model-railroading work.  The most common thing to use is 'overproof' isopropyl (straight rubbing alcohol, with no glycerin or other additives) in 99% or 97% strength if you can find it, 91% if you're cheap.  You may need a little elbow grease to get the crap fully off, too

I went to using MG Chemicals 8351 liquid no-clean, dispensed from a disposable syringe with the needle ground off blunt.  I've never found the 'core' solder to provide nearly enough fluxing action in the right place to get the whole joint to set up bright and solid, whereas a small chip of solid shaped the way I want can be held in place under the flux close to the joint where only a small amount of heat can get the work accomplished.  

And I'll clean the joint afterward.

 

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Posted by hon30critter on Sunday, December 15, 2019 10:19 PM

BigDaddy
Randy Rinker has recommended the Xytronic   It's less expensive than yours https://www.amazon.com/Xytronic-LF-389D-Mini-Type-Digital-Soldering/dp/B00E4WUN8O

I will absolutely second Randy's recommendation! My Xytronic soldering iron is the best piece of equipment that I have ever used! For years I struggled with keeping the tips clean on a variety of Weller and other pencil tip irons with very little success. Yes, I could solder properly but keeping the tip clean was a huge challenge. Based on Randy's recommendation, I bought an Xytronics LF 399-D soldering station and I am amazed by how well it works. The tip stays clean! There is a bit of carbon buildup after making a few joints, but it wipes off easily in the included brass sponge leaving a beautiful shiny tip.

I strongly recommend investing in a Xytronic soldering iron. Until you do, you probably will never know how easy soldering can be!

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by gregc on Monday, December 16, 2019 4:06 AM

Overmod
The crap in typical rosin-core over-the-counter solder most definitely should be cleaned off

i've never seen this done during my career in the telecom industry when prototype boards are soldered.   There is very little rosin residue when done properly.

I know of no model railroader who uses paste flux nor wipes down their solder joints.

i would guess that if you choose to use paste flux, it probably covers more area than needed, more than needed used, there's lots of residue and needs be cleaned up.

 

soldering is simple.   Good results come with inexpensive tools (TP-13) and with just a little practice.  Definetly a less is better thing.

greg - Philadelphia & Reading / Reading

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Posted by Overmod on Monday, December 16, 2019 11:31 AM

gregc
There is very little rosin residue when done properly.

At the scale I was working with electronics, even a little was 'too much' Smile  

The problem is, at least in my opinion, that many 'hobbyist joints' involve more solder, and perhaps more tries, than an expert would use, and there may be excess flux around the joint after it is complete.  

I know of no model railroader who uses paste flux nor wipes down their solder joints. i would guess that if you choose to use paste flux, it probably covers more area than needed, more than needed used, there's lots of residue and needs be cleaned up.  

Where did paste flux come into this discussion in the first place?  

I confess that I have used paste flux on occasion in the past, including as a quick 'dip' before cleaning the tip in the bronze wool, but for serious joints it'll be a minimum of liquid.  

I didn't learn how to really solder until going through the machine-shop course at PPL.  I'd always thought you needed a sort of blob or fillet between, say, the trace and component leads.  It was a great delight to see just how little was required to tin a surface, or to get a thorough bond between two pieces just to show a bright line between them.   It's relatively simple, but also an art.

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Posted by gregc on Monday, December 16, 2019 12:15 PM

Overmod
I'd always thought you needed a sort of blob or fillet between, say, the trace and component leads.  It was a great delight to see just how little was required to tin a surface, or to get a thorough bond between two pieces just to show a bright line between them.

gregc
solder is not a glue, it actually allows a chemical bond between the two pieces of metal. 

greg - Philadelphia & Reading / Reading

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Posted by wvg_ca on Monday, December 16, 2019 12:27 PM

When i normally use solder flux, i use the paste version, for what it' worth ..solder paste is a different animal, it has fine solder within it ..

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Posted by BATMAN on Monday, December 16, 2019 12:35 PM

I also have a Xytronic soldering station and wish I had not waited so long to get it. It was a case of not knowing what I didn't know.

I bought a bundle of five pieces of flex track at a train show for a dollar to practice soldering on. It was a dollar well spent as I can whip a feeder on or solder a joiner quick and easy and looks good. 

Brent

"All of the world's problems are the result of the difference between how we think and how the world works."

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Posted by Overmod on Monday, December 16, 2019 1:01 PM

wvg_ca
When i normally use solder flux, i use the paste version, for what it's worth ... solder paste is a different animal, it has fine solder within it...

You're right; those are actually two different products.  I think there was a "correct" technical name for the latter; it used to be sold in the back pages of Popular Mechanics as 'emergency solder' that could be applied with a match or lighter, or without need to manipulate a coil of wire solder 'in the field' -- fine particles of a given type of solder held in a gel or thicker composition of flux and sticking to the joint regardless of alignment.

"Paste flux" is just flux with no solder incorporated in it.  This is the stuff you can buy at home-improvement stores in those little plastic tubs... I think usually its active ingredient is zinc chloride or something like it.  It's sold as an alternative to 'acid' flux for pipe work.  Personally I wouldn't use either for fine work... or without passivating and then rinsing. 

Good liquid no-clean is nominally expensive per pint, but if dispensing from a syringe a little goes a very long way.

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Posted by Overmod on Monday, December 16, 2019 1:09 PM

gregc
solder is not a glue, it actually allows a chemical bond between the two pieces of metal.

I think you've got that backward.  I know you know exactly what is up, but some people reading that might be confused by the words used.

Glue is what uses a chemical bond to join the two surfaces, like cyanoacrylate for very thin bonds and epoxy for thicker ones.  A solder joint is like a lower temperature braze joint: it's a mechanical bond between the two surfaces.  (Technically you could call metallic bonding a kind of 'chemical' bonding, but that's not what most people would interpret chemical bonding to be)

I was a bit of a fusion-welding snob in high school; it came as a great delight to discover that brazed joints can be substantially as strong as fusion welds in the native metal in some circumstances...

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Posted by gregc on Monday, December 16, 2019 1:37 PM

you're right.   I should have said metallic

greg - Philadelphia & Reading / Reading

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Posted by The Milwaukee Road Warrior on Monday, December 16, 2019 9:28 PM

Do I need to order other parts at the same time I order the soldering kit?  I've read that certain tips (?) can be hard to get after the fact?

Andy

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Posted by BATMAN on Monday, December 16, 2019 10:08 PM

The Milwaukee Road Warrior

Do I need to order other parts at the same time I order the soldering kit?  I've read that certain tips (?) can be hard to get after the fact?

 

I know of two people that have ordered tips off Ebay from China and they are as good as any they have bought and way cheaper. You can often get sets of five different tips for a great price. Usually takes ten days to get here. 

Brent

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Posted by hon30critter on Monday, December 16, 2019 10:12 PM

The Milwaukee Road Warrior
Do I need to order other parts at the same time I order the soldering kit?  I've read that certain tips (?) can be hard to get after the fact?

What kit are considering ordering? If you are considering ordering an Xytronic LF-389D system, there are lots of optional tips:

http://www.xytronic-usa.com/shop/category.aspx?catid=26

Where you might have trouble getting replacement tips is if you order an off name brand.

Dave

 

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Posted by The Milwaukee Road Warrior on Thursday, December 19, 2019 5:22 PM

 What kit are considering ordering? If you are considering ordering an Xytronic LF-389D system, there are lots of optional tips:

http://www.xytronic-usa.com/shop/category.aspx?catid=26

Where you might have trouble getting replacement tips is if you order an off name brand.

Dave

 

I will be getting one of two xytronics I've looked at since that brand was suggested here.

Andy

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