Reattaching Broken Motor Winding Wire

It looks like you have just enough wire left sticking out to splice on a new piece if you have the tools.

Were I working on your whistle, I would do the following:

Use a sharp knife, like an Xacto with a #11 blade to scrape away the insulation from the end of the wire.
(back up the wire stub with a flat bladed screwdriver tip)

Use a fine pointed needle nose pliers to bend a tiny hook in the end of the wire.

Scrape the insulation from the end of a wire of similar sized length of magnet wire and put a small matching hook in the end.

Join the hooks and bend them closed.
Solder the joint.
Slip a piece of tubing over the joint.

By the way, this sort of field coil wire break is very common.
For this reason, I almost always unsolder the field coil wires when removing a brush plate, or what ever they are attached to avoid flexing them excessively.

what is "magnet wire"?

You can use any reasonably sized insulated wire.  Magnet wire is what you see on the field coil that you're repairing. 

Truthfully, I wouldn't try to bend the wire, you may break it farther down.  I'd just scrape the insulation off and tin the lead end about 1/4" or even 3/16.  Tin the end of the wire to connect to it and then just solder them together side by side.  Slip some heatshrink down over the connection and you're done.

C W Burfle posted:

It looks like you have just enough wire left sticking out to splice on a new piece if you have the tools.

By the way, this sort of field coil wire break is very common.
For this reason, I almost always unsolder the field coil wires when removing a brush plate, or what ever they are attached to avoid flexing them excessively.

 

Ha!  I looked more closely at the picture now and there is indeed the slightest bit more wire than I originally thought - it seems to be moving around a bit when I handle it.  Not enough to hook onto (the picture is a bit deceiving) - but perhaps 1/2 of a mm.  I little tinkering reminded me that the field is a conductor - so I'm thinking that perhaps I could just solder that little bit of wire onto the core that's beneath it and all should be good.  Has anyone else done this?

The bummer is that I was in the process of adding some quick disconnect plugs to make it easier to remove the motor for oiling and the like when I went and broke it - I was just one bend of the wire too late.  I think going forward, to your last point, I'm going to heat shrink and then physically attach the windings on these little motors to the sides of the motor so they don't have to flex ever again.

I can't imagine why you can do what I described to tack a wire to that little end.  If you can see it there, you should be able to solder to it.

gunrunnerjohn posted:

I can't imagine why you can do what I described to tack a wire to that little end.  If you can see it there, you should be able to solder to it.

I think you meant "cannot", right?  You're probably right - it will just be a little trickier than just blobbing some solder into the general area to connect the wire to the core.  I was thinking my approach might be an alternative way to solve the problem and was wondering if by connecting the core to the winding at that point it might have unintended consequences (although it seems to work find when I manually connected them a few minutes ago).

Soldering to the lamination may be harder than soldering a bit of wire onto that end, but I guess you'll find out.

Truthfully, I wouldn't try to bend the wire, you may break it farther down.

It could, but it hasn't happened to me yet. I've done the repair many times.

I think the wire develops a weak spot from repeated bending. Once there is a weak spot, that is where it will bend if you move the wire around. Bend it enough times, and it breaks.

 Tin the end of the wire to connect to it and then just solder them together side by side. 

I've tried to do the repair in this manner, and found it too difficult to hold the wires in alignment and steady.
I have put the two wires side by side, and wrapped them with another wire, such as a single strand taken from some stranded hook up wire. That works if you have room to get the wrapping wire on.

There is usually more than one way to make a repair.

C W Burfle posted:

There is usually more than one way to make a repair.

Very true!