Solder connections are rusting!

Saying that the type of solder and flux doesn't matter is naive. Depending upon what solder, flux, and wire was used, you may actually have to unsolder and clean everything really well to stop the corrosive processes set underway (and use more suitable supplies). So please share what was used...

Aside from that, now that the damage is done, it may not be that bad and just be a flux residue that is left and could be cleaned up with something like an alcohol on a cotton swab, so give that a shot and report back as well.

It looks like flux that has aged. Some alcohol and a tooth brush should fix it.

BMORAN4

Thank you for the response. I no longer have the flux or solder. The layout is wired and complete and I did not keep any of it. I am also unable to clean the connections without completing tearing up all the track and ballast. I do know the solder and flux was old. Got it off of my pap's tool bench. So whatever was popular back in the 80's and 90's is probably what it was. The track in the picture is some leftover track I had in a drawer and noticed the rust on it!!!! Its approximately 7 years old from the time of soldering. 

OK, but you can stop calling it rust now. It is old flux that has turned color with age.

Rust is iron oxide and this is not that.

If it is a gnarly flux residue (especially ones that are very acidic; hence the importance of understanding what was used), it may eventually eat away at the connection (and connection points). So your options are to clean it up now and prevent total failure, or wait for total failure and have less (or nothing)  to work with in terms of having any thing left to resolder for repair.

Royboy

That would explain why the one connection is discolored (not rusted). And the other connection (not pictured) looks fine.

When you solder a joint always clean off the the excess flux with a rag and you won’t get an acid reaction.

Mikey

Well that darn flux anyway! So it will eventually eat all the way through then?

Try some baking soda, it will neutralize acid in the flux. You can mix baking soda with a little water to make a paste. Use a tooth brush to clean the joints with the paste. Rinse it off with water. I'd try that on a couple of those solder joints and see how it works, making sure it doesn't harm your track or anything else involved. Pretty sure it will be fine, but I have never tried this on any type of track, better to be safe than sorry.  

Never mind, I didn't see you post earlier about the track all being laid already.  It doesn't look too bad for being there for 7 years. I think I would just let it go and see what happens. It's also possible you could end up moving, changing the layout, or other layout rework before it all rots away anyway. 

Not all is lost! If I notice a power failure on my rails I can bring up new wire leads between the ties and re-solder the connections to the rails themselves using the "right" flux. And also make sure to clean it off afterwards!

RTR, 

I unfortunately can not access the connections unless I tear up all the track and ballast. 

I just saw that and edited my previous post above, missed that part earlier. You want to use electronics solder with 'rosin core' flux from now on for all your track soldering. If you need any added flux make sure it's for electronics only and not the acid type.

I'm not even thinking about tearing all this track up! I'll get battery operated engines before I do that!!!🤣

The one and ONLY type of solder that should be used on electrical connections is rosin core solder. There is absolutely no need to use a separate flux!!

I have worked in the electronics repair industry for decades. I have made tens of thousands of solder joints. I have never, ever, used any type of flux paste or liquid for any of those solder joints. The rosin-based flux is in the core of the solder! That’s why it’s called “rosin core solder.”

I agree with others here that this is not rust. It’s just old, excess flux. If you were to heat these joints, that stuff would bubble up and evaporate. If you don’t use any flux and just rely on the flux in the solder, you won’t have this problem.

(Edit)

For the second picture, I don't think you need all the heat shrink. You could probably take a piece of solid 14 gauge copper wire (house wire, stripped and cut to length), lay it across two tabs of the center rail and solder away. Good, fast, and cheap(er).

Rich,

Enuff said!

Rich,

So back to my first posted question. 

1. Is the flux (not rust) just on the surface and everything is handy dandy?

Or

2. Is the flux (not rust) going to deteriorate the connections to the point I lose continuity?

Only a LITTLE flux goes a long way :-)

Fargus posted:

Rich,

So back to my first posted question. 

1. Is the flux (not rust) just on the surface and everything is handy dandy?
Everything is fine. It's on the surface. Don't worry about it.

2. Is the flux (not rust) going to deteriorate the connections to the point I lose continuity?
No, it will not.

What's a little excess flux among friends...

Until you use no lead solder, you don't know what trouble is.

Awesome 👍👍👍👍👍. Thank you all for replying! I can sleep a little more sound tonight! I'm never using flux ever again!!!

Post closed.......thanks again everyone!

Nice looking scenery!  Unless your pap was a plumber, I would guess that the solder you used is not acid-core.  It looks like you can't really do anything about it at this point, so I would run your trains and not worry about it.

Jerry, I'd love to see more pics of your pike. That is wonderful scenery and the best looking Fastrack I've ever seen a pic of.

Flux wasn't the problem, the problem was you used acid based flux!  That's primarily used for stuff like plumbing.  If you used the proper flux for electronics, rosin based, you wouldn't have rust.

gunrunnerjohn posted:

Flux wasn't the problem, the problem was you used acid based flux!  That's primarily used for stuff like plumbing.  If you used the proper flux for electronics, rosin based, you wouldn't have rust.

Thanks John once again for your input....I was thinking the same thing....all the best....joe