Topics

Cut wiring harness


Jamie Ostrowski
 

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 generate.

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.


kim.herron@sbcglobal.net
 

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
generate.

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
k9uwa@...
Visit our Web Site at:
http://www.JohnJeanAntiqueRadio.com
4836 Ranch Road
Leo, IN 46765
USA
1-260-637-6426


Leon Robinson
 

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
generate.

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
k9uwa@...
Visit our Web Site at:
http://www.JohnJeanAntiqueRadio.com
4836 Ranch Road
Leo, IN 46765
USA
1-260-637-6426


Dwayne Reid
 

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 spools.

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 diameter.

dwayne

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
generate.

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
k9uwa@...
Visit our Web Site at:
http://www.JohnJeanAntiqueRadio.com
4836 Ranch Road
Leo, IN 46765
USA
1-260-637-6426





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


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
spools.

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
diameter.

dwayne


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
generate.

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
k9uwa@...
Visit our Web Site at:
http://www.JohnJeanAntiqueRadio.com
4836 Ranch Road
Leo, IN 46765
USA
1-260-637-6426






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





kim.herron@sbcglobal.net
 

I wouldn't worry about the wire color or the tracers.  Funny thing about the electrons.  They don't have any idea what color the wire is.  :-O.

Kim Herron W8ZV kim.herron@... 1-616-677-3706

On Friday, August 7, 2020, 8:11:18 PM EDT, Jamie Ostrowski <jamie.ostrowski@...> wrote:

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
spools.

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
diameter.

dwayne


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
generate.

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
k9uwa@...
Visit our Web Site at:
http://www.JohnJeanAntiqueRadio.com
4836 Ranch Road
Leo, IN 46765
USA
1-260-637-6426






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





Roy Thistle
 

On Fri, Aug 7, 2020 at 09:18 AM, kim.herron@... wrote:


so large that you can't get the loom back in
place. ...stagger your repair splices so that
you can get it back together.
The obstacle that arose was the bulk, created by the accumulation of splices...getting the spliced loom back in position was not possible... staggering helps... also reducing the number of splices by replacing as many runs as convenient (some are usually easy to do... and then running a constructed loom (of those replacements) in parallel... or sometimes rerouting the new loom more conveniently. I've used inline multi-pole connectors... sometimes panel (or chassis mount) plug and socket... and sometimes terminal blocks (or stacked terminal blocks)... or retrofitted in a junction box.
Some insight is to be gleaned from the amazing number of wire T&M guys mannage to squeeze through the approximately 1cm. by 5cm. opening on the plugins for mux and switch plugins. (all the pairs are connected to screw down, or spring loaded, terminal blocks, on the plugin.) Some insight can be gained from pstn guys who used to do splicing, of multicondutor cable runs, all the time.
Signal carrying pairs need attention as to the point to point re-connection (and splicing), according to the wire/cable used (possibly length too, as well as shielding)... and of course routing.
Although you undoubtedly know, the 556 is almost symmetrical... so getting the power supply working first, and then one beam/channel working...before getting the other... might be a reasonable option.