Topic: SOLDERING-COPPER WIRE WONT TIN

[BASKET_CASE]

I am resoldering new wires to some of the control switches and the rectifier. I have soldering experience but for some reason the stock wires wont tin/wet. I have attempted both lead free solder (home depot) and 60/40 solder (ebay sourced from china). I have used varying temps, heated the contact and the wire itself even to the point the sleeving will melt, but the solder will just float above the wire and never tin/wet. I have heard some wire may have a coating, so i tried to lightly wire dremel which proved fruitless. Seriously, i feel i have attempted every technique to tin under the sun.  ANY IDEAS?

[Bodi]

Try soldering flux. The acid type used for plumbing usually works when all else fails. Tin the wire then clean the residual flux off as well as you can, the stuff can cause corrosion of non-copper parts (ie the switch) - not a problem with plumbing.

[madmtnmotors]

Try soldering flux. The acid type used for plumbing usually works when all else fails. Tin the wire then clean the residual flux off as well as you can, the stuff can cause corrosion of non-copper parts (ie the switch) - not a problem with plumbing.

+1

For electrical work I prefer "flux-core" solder.

[Bodi]

The resin flux in electronic solder is usually good enough but for some corroded wires where you don't have the luxury of enough length to shorten them and get to clean copper... acid flux usually allows good tinning.
I should NOT be used for electrical/electronic use but when necessary, and if cleaned off well (isopropyl or even acetone), it can save a job. El Cheapo oriental components (like phono jacks or switches) with steel (?) terminals that have sat for a long time are notorious for being difficult to tin without it.

[lajos]

Lead free solder is harder to work with because it melts at a higher temperature. Wikipedia says "unfortunately, most lead-free solders are not eutectic formulations, melting at around 250 °C (482 °F), making it more difficult to create reliable joints with them."

I also prefer the flux core solder as others suggested above. Works on most jobs, but sometimes you need a bit more:

Get a bottle of liquid rosin flux (comes in a bottle or pen) or rosin paste. Apply it to the wires and they should take the solder. My favorite is MG Chemicals 835 Liquid Rosin Flux (can find it on amazon or local electronics stores).

Acid based flux as last resort. If not cleaned up correctly it will start corrosion and the fumes are awful.

[Duke McDukiedook]

Try soldering flux. The acid type used for plumbing usually works when all else fails. Tin the wire then clean the residual flux off as well as you can, the stuff can cause corrosion of non-copper parts (ie the switch) - not a problem with plumbing.

+1

For electrical work I prefer "flux-core" solder.

Get electrical soldering flux and a hot iron and apply the flux liberally after cleaning it up as best you can with steel wool.
Leave the plumbing flux for sweating pipes.
Be sure to tin your iron often in the process.

[Vinhead1957]

I'm against soldering but if you must make sure you have clean conductors and a good mechanical connection. Solder should not be used as a glue so to speak. Get the wire hot enough to melt the flux and then melt the solder from the wire heat not the iron. It should flow easily throughout the wire.   Now the warning! Once a stranded wire is soldered it becomes a solid wire. Solid wires do not flex very well and usually break near the solder connection.   I prefer crimp connection. It allows the stranded wires to flex.  Vintage connector has all the right stuff to get that harness back to original shape.   Crimper to boot

[flybox1]

Try soldering flux. The acid type used for plumbing usually works when all else fails. Tin the wire then clean the residual flux off as well as you can, the stuff can cause corrosion of non-copper parts (ie the switch) - not a problem with plumbing.

+1

For electrical work I prefer "flux-core" solder.

+2 
You can get flux at any hobby/craft store.

[Muckinfuss]

This might be one of those things where everyone has their preference, but I was taught in high school shop class a tinning method that I still use to this day....and it's never failed me.  Use plain old powdered white brazing flux....available just about anywhere like tractor supply, home depot etc. and it's cheap.  Its primary component is boron based.....heat the wire to hot hot and dip it into the flux, remove and then solder with solid or rosin core.  I have a tiny refillable torch that I use for the first step and a plain old two step trigger soldering gun for the second.  It encapsulates the corrosion and 'lifts' it,  was how I remember the explanation....in turn your solder/braze etc. can flow and bond without oxygen corrosion messing with you.  Cut back the insulation more than usual, do your tin and then trim the wire to correct the exposed length.

[eigenvector]

Has to be corrosion.  I rewired the control switches for my CB550 and I didn't need to use flux or any special techniques other than clean wire.  I think you'd be surprised just how corroded that wire is.

The turn signal switch gave me quite a challenge - the original soldering wasn't particularly clean to begin with, coupled with 40 years of water, grease, dead spiders , yeah it was a real challenge.

[madmtnmotors]

I rewired the control switches for my CB550 and I didn't need to use flux or any special techniques other than clean wire.

Rosin core electrical solder has the flux "built in" and would not require anything other than "clean wire".

[Retro Rocket]

Coke {coka cola}, or even fresh lemon juice works well as a flux, done it hundreds of times successfully....

[eigenvector]

I rewired the control switches for my CB550 and I didn't need to use flux or any special techniques other than clean wire.

Rosin core electrical solder has the flux "built in" and would not require anything other than "clean wire".

Yes it does doesn't it.  So what are you commenting about?

[madmtnmotors]

I rewired the control switches for my CB550 and I didn't need to use flux or any special techniques other than clean wire.

Rosin core electrical solder has the flux "built in" and would not require anything other than "clean wire".

Yes it does doesn't it.  So what are you commenting about?

Just wondering if you were using flux core solder, thus precluding the use of any other sort of flux. If you're using flux core solder then you are using flux. I've never had much luck soldering without some sort of flux, whether it be a separate product, or in the form of flux core solder. I prefer rosin core solder for electrical work since acid core solder seems a little too corrosive IMHO.

[disco]

The control switches or rectifier are acting like a heat sink and dissipating the heat. You need to get enough heat into those items then the solder will 'wet' & stick.