Try Using Just Your Fingernails

For very tiny wires I have successfully used just my nails to pull a small bit of insulation off while holding the wire with long-nose pliers. Or you could clean any solder off the tip of your soldering iron and try melting the insulation off, but use the pliers as a heat sink.

What is it?

What sort of loco are we talking about?

In my experience, stripping and soldering those fine wires is not difficult, but it does require care.  I typically use a SHARP single edge razor blade or hobby knife and gently roll it over the wire.  Ideally, I'd like to slice almost through the insulation, and the weight of the blade is usually enough to do the job.  Then a quick tug on the end of the insulation will pull the stripped piece free.  If you can, twist as you pull, and the wire will be twisted and ready for tinning.  Tin with a clean, hot iron and a drop of flux.  Afterward, it's a cinch to solder the wire in place.

For things like Athearn trucks, it can be a little more difficult to solder to the heavy metal tabs.  It takes a larger iron, but if you get steel hot and flux it well, it takes solder nicely.

It's worth learning how to work with those fine wires.  DCC decoders use them as well, and if you ever get into installing decoders or re-wiring models (it happens more often than you'd think, if you start kitbashing) you'll find yourself working with those wires a lot.

Fingernails

I agree with the fingernails option as it has also worked well for me. I would add that it helps if you ever so lightly press a new, sharp hobby knife or razor blade against the insulation from opposite sides right where you will put your fingernails. Rock the knife back and forth a few times but don't press hard enough to cut into the wire. The intent is to create a weak point in the insulation, not to cut through it.

Older Athearn HO

I've got a nice blob of solder on the steel piece.  I heated it up until that solder liquified, then I tried to just stick the wire into the molten solder.  It worked, but as I only had about three strands of the wire it didn't last.  

I was thinking about burning the insulation off.  I tried the finger nail thing but couldn't get it to cut the insulation, I rolled a razor lightly over the insulation but when I pulled it off a few strands of wire came with it.  I'll try again when I get home tonight.  

Thanks for the suggestions.  

Randy  

Invest in a #24 TO#32 SIZE wire stripper.

This is an indespensible tool for working with small wire.  All decoders use #28 or smaller wire.  Also most feed wires coming from the locomotive trucks are this size.  Other that that, use the above suggestions to get you by for now and work SLOW!  I also recommend tiny micro alligator clips as heat sinks to avoid melting the insulation more than needed.

Why not replace the wire?

Athearn BB locomotives came with a copper strip that ran across the top of both gear towers to the motor.  If this is an older Athearn BB locomotive, the previous owner probably replaced the clip with a very small gage stranded wire.  Why not just replace the  wire?  I use 18 ga stranded wire.  It works great.

The wire is part of the DCC decoder

I don't think I can easily replace the wire.  I'm pretty sure it is wired directly to the decoder.  I'll have to check tonight, but last night on first glance it appeared easier to just re-solder the wire that was hanging loose.   

thanks, 

Randy

More options

I've had bad luck trying to melt or burn insulation off of wires.  I usually end up with residue of some sort which results in a poor tinning and poor joint.

If you have a deft hand, you can also use wire cutters, nippers, or the cutters built into most pliers.  The trick is to grip the insulation with the sharp edge, but not cut through it, and them pull the wire away, leaving a little bit of insulation in the jaws.  I don't like to use that technique on wire that small because it's far too easy to cut through the whole wire, but it does work sometimes.

Another technique I've used is to use a sharp blade and scrape the insulation away.  It's hard to get all of it, but you can usually get enough to make a decent joint, and it's a little easier to keep from cutting through the wire.

Easy Option

If you are going to do very

Stripper

Bruce is 100% correct, in fact, decoder work aside, if you are going to be doing any amount of wiring a stripper is a must have tool.  The Klein stripper Bruce provides a link to is a top of the line tool used by professionals and is available at a great price!  Also having a stripper for larger 12-20 gauge wire is a good investment.

Thanks for all the suggestions

I've ordered a stripper and a soldering tweezer/heat sink thing.  I think those will help a lot.  I appreciate all the tips. 

Randy

Got it fixed, thanks!

I got my wire stripper and heat sink tweezers from MicroMark and those did the trick.  I was able to pretty easily solder the wire back on and the loco is running just fine.  Thanks for all the help and suggestions!  

Randy