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jim rozen
 
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In article s.com, Karl
Townsend says...

I have a multi conductor cable with very small wires. I guess 22 or 24
gauge.


Those are huge wires. :^)

My suggestion would be *not* terminate those under screws.

If it's a standard, double screw terminal board barrier strip,
take out one of the screws and solder the wires directly to
the terminal.

To strip those I use a standard el-cheapo stripper made of
what looks like strap iron. Those typically have a limit
screw that allows them to only close so far, so the V-shaped
notches only cut the insulation. I find that the simple
ones work better, overall, than the fancy ones.

I suggest you do like I do, and throw away the limit screw,
and do it by feel.

Strip only 0.1 inch or so of insulation, and tin the wires
without melting much of the insulation if you can. If
you can get the solder to flow up under the insulation
a bit, that's OK even if it cooks up the plastic a teeny
bit. Gives it extra strength at the stress point.

Then tin the barrier strip, and then tack the wires onto
the region where you tinned them.

The key to this approach is you need to mechanically strain
relieve the cable jacket near the strip so the wires *never*
see any stress. Unless you have a strain relief set up
somehow, I would suggest you drill a couple of holes in
whatever is supporting the barrier strip. Drill two pairs
of holes, with each pair separated by about the diameter
of the cable jacket. Then pass a nylon zip tie through the
holes from underneath and cinch them down across the cable
jacket, immobilizing it.

The trouble with crimp or solder lugs on conductors of this
size, is that eventually the wire will flex near the termination
and fail at that point. Also it's tough to get crimp lugs
that work really reliably on 24 gage conductors.

A microscope is actually pretty handy for stuff like this.

Jim


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