On Tue, 08 Feb 2005 19:15:55 -0800, the renowned Grant Erwin
wrote:

The little Dumore Carvit I was so happy to find recently had severe fraying
of the cord right where it went into the motor housing. Today I spun it up
and yup, it went *pop*! I cut off the wires and tore the motor apart. Hmm.
Doesn't look like I can get back in there at all. Wire now only sticking out ¼".
I very carefully working with magnifiers stripped off about 1/8", now I have 2
ultra-short stubs of stranded copper, maybe 14 or 16 gauge, to which I have to
solder a new power cord. It's a universally wound motor with brushes and the
brush housings don't look removable from the stator shell and the stator itself
is riveted to the brush housings, so it really doesn't look like I'm going to
get inside there to do a decent splice.

I'm thinking of getting some skinny modelers brass tubing, slitting it
lengthwise maybe 1/2" with a Dremel tool, then cutting off a couple of 1/4"
thin brass crimp tubes and first making a mechanical connection by crimping,
then soldering into the slit, then sliding on heat shrink and insulating each
crimp, then sliding on another layer of heat shrink, then building up a layer
of electrical tape, the good stuff so it tapers up and eventually catches the
teeny 1/8" of old insulation left, then finally sliding on a bigger piece of
heat shrink to make it look as clean as possible, then looping the wire to
a tie point on the body of the machine so there should never be any stress on
the splice.

I know some of you guys are pretty handy on an electronics bench, how does this
sound to you?

Grant Erwin

Sounds good. Why do you want to slit the tubing lengthwise? Why not
just get the smallest size the wire will fit into and crimp (or even
better, swage if you have such a tool) it onto the wire.

When it breaks again it will break not at the tubing but where the
solder ends (past the tubing), because the solder-filled part will be
rigid and the part just after that will flex. That probably means it's
toast. You might want to pot the stubs and homemade crimp connectors
into epoxy to keep them from the short end from moving as much as
possible, if that makes sense. It goes without saying that you must
use electronic grade solder not acid-core stuff.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
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