How to solder very thin stranded wire?

The enamel and the fibers don't dissolve in the solder, they just burn away. And it's not instant, the removal of the varnish and tinning of the strands. Sometimes I need to add more solder as the varnish and fibers burn away. I've never heard of SolderEze coated wire. It sounds like useful stuff. I'm gonna look for some. Thanks, Eric

It may not even exist anymore. I last used it in 1987, when I was at GenRad, Phoenix.

I found this link....

which implies it's no more. ...Jim Thompson

Interesting. I find that they still sell "solderable Beldsol", which is specified to solder without stripping at 750 F. A bit hotter iron than usual, but no blue flames required.

Cheers

Phil Hobbs

Is this for the same reason solder tips dissolve in solder (slowly).

I only use resin core, never acid core, and still the tips disappear after years. I wouldn't mind except I had trouble finding new screw-on tips a few years ago, because in the hobbyist-priced irons they've gone back to screw-in tips.

landfill

That is the theory... If you slowly feed something like 32 or higher AWG wire onto a hot, heavily tinned, tip you can watch it dissapear.

I just tried it with one strand from 24 AWG stranded wire, which is made from 7 strands of 32 AWG. I held the iron on the wire for about

Thanks. That makes sense, but I'm still skeptical. So, I tried it again, this time with a thicker #28 bare copper wire on both my 750F lead-tin (60/40) iron tip and my 850F RoHS tip. 15 minutes of applied heat and I get the same result as before... nothing happened (except a well tinned piece of wire and a pile of dross).

Digging, I found: "Properties of Alloys of Multicore.. Solder Wires" Multicore Savbit Solder is produced especially to overcome the problem of ordinary tin/lead solders dissolving copper. It is an alloy to which a precise amount of copper has been added so that no further copper absorption should take place during soldering.

From the graph, it appears that pure tin is the worst, with 60/40 being a close second. However, if there's any copper in the solder, the copper wire doesn't want to dissolve. I'm not sure what's in the RoHS solder on my bench. The label fell off long ago. I'll find some more that doesn't have copper in it and see what happens.

I'll see if I can find some finer wire and try again. I want to see the wire "disappear".

The cheap lead-free stuff I have has 0.7% Cu.

Best regards, Spehro Pefhany

Probably should have said - single strand of soft, >= 32 AWG UNTINNED copper wire as in "solder ez" magnet wire. 32 will dissolve (I know) and 41 awg is damn near impossible to solder to. Only thing that works is "reflow" (tin the part and heat it then touch the wire to it - or wrap it around a tinned heavier lead with several turns then reflow. In production quantities flux the part then a quick dip in a just-skimmed solder pot)

There is a real art to soldering fine gauge wire and litz wire.

Did you first dip the wire tail in acetone to clean off the fibers and any form of coating on the wire?

After do so, you then use a small amount of flux..

It has worked for me in the past for types of fine wire bundle in fiber fillers.

Jamie

really, the junk I have has 5% in it and it hate it ! ;)

Jamie