Re: Cut wiring harness

Jamie Ostrowski

Thanks everyone for the tips. I'll try experimenting with my splicing
technique using these ideas and see if I can come up with a satisfactory
joint. It sure would be nice if I can find wire with matching tracers but
so far I haven't had any luck, which is unfortunate.

On Fri, Aug 7, 2020 at 2:08 PM Dwayne Reid <dwayner@...> wrote:

Hi there, Jamie.

One possible alternative is to use 30 AWG wire to hold the lap joints
together before soldering. However, this requires more room to work.

This type of connection is required for some levels high-reliability
work (IPC Level 3S). Strip the conductors, wrap the lap joint with
thin tinned wire, solder. Use the minimum amount of solder
necessary, don't let the solder wick under the conductor
insulation. We purchase 30 AWG tinned wire from Belden in multi-pound

The downside of this technique is that you have to be able to
separate the conductors far enough for your fingers (or round-nose
tweezers) to fish the wrapping wire around the conductor. But it
makes extremely reliable connections that don't exceed the insulation


At 10:50 AM 8/7/2020, Leon Robinson wrote:

In these conditions I would suggest that the splices be lap soldered and
shrink tube to minimize the size of the splices.
I know lap splices are frowned upon but here I think it is the
better solution.

Leon Robinson K5JLR

Political Correctness is a Political Disease.

Politicians and Diapers should be changed
often and for the same reasons.

On Friday, August 7, 2020, 11:18:30 AM CDT,
kim.herron@... <kim.herron@...> wrote:

Yes I have done this before, in several arenas. Cars, AM
transmitters, linear amplifiers, custom built test
equipment, etc. IF you have BOTH
pieces that have been cut, you can match up the wire
colors and splice them together. You will want to cut the
looms back on both ends so that your repairs don't
become so large that you can't get the loom back in
place. You'll need to stagger your repair splices so that
you can get it back together. That will require some
replacement wire, and lots of shrink tube. Doing this will
be much easier that trying to recreate the harness. I've
done that too, but the work involved here would be
excessive. The splice route is the way to go.

If you have the original manual with all the wiring info, it
makes it easier to ID what goes where.

On 7 Aug 2020 at 8:58, Jamie Ostrowski wrote:

I bought a pair of 556 oscilloscopes from an electronics scrapper
that I am restoring. I think I'm able to get the rest of the parts
that were harvested from the person who sold them to the scrapper,
but unfortunately, they sliced through a couple of wire harnesses.
The point where they were sliced the harnesses are made up of what
looks like 24 gauge tinned wire and others look like maybe 20 gauge.
I'm trying to weigh whether I should splice the looms back together
or if I should re-wire. Re-wiring looks like it's going to be an
incredibly painful process that will take me literally probably 100
hours of work per scope. Just hunting down originally correct color
coding wires is going to be a nightmare, and then routing them
correctly and re-tying the looms......whew.

It's unbelievable how much work one snip of a wire cutter can

Has anyone gone down a path like this before in a restoration and do
you have any tips?

Fortunately I do have a third complete 556 that I can use as a model
to compare with.

John Goller, K9UWA & Jean Goller, N9PXF
Antique Radio Restorations
Visit our Web Site at:
4836 Ranch Road
Leo, IN 46765

Dwayne Reid <dwayner@...>
Trinity Electronics Systems Ltd Edmonton, AB, CANADA
780-489-3199 voice 780-487-6397 fax 888-489-3199 Toll Free
Custom Electronics Design and Manufacturing

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