Wire Insulation renewal.

[Station X]

Many of the wires in a radio I'm currently restoring have rubber insulation which has gone brittle. Rather than renew the wires I reinsulated them. I unsoldered one end of the wire and removed the old insulation. It was so decayed that it came off without the need to use wire strippers.

Then I simply threaded new insulating sleeving on to the wire before resoldering it. In the case of long wires it helps to solder a temporary length of thin solid wire to the end of the existing wire to act as a draw wire.

Suitable sleeving is available from Farnell, CPC etc. in a range of colours.

[Nickthedentist]

A very interesting idea!

What was the sleeving you used made from? PVC? Does it look reasonable? Any chance of a pic?

Finally, what do you think are the advantages of your technique compared with just replacing the whole wire? Authenticity, speed, cost?

Thanks for a useful trick,
Nick.

[stephanie]

Sometimes heatshrink tubing helps, especially when one end of the wire is in an inaccessible place or permanently joined to something (such as an audio out transformer).

Usually I prefer to just replace the wire. Stuff is cheap, anyway.

[zak]

I have always removed the perished rubber and fit sleeving (of the appropriate colour) over the wire,I have done this for years,no need to disturb the wire.Generally I prefer to leave alone,unless the covering is badly damaged,and there is risk of it touching some other connection etc.

[Station X]

The wire I'm sleeving is of the stranded variety with the original rubber insulation in intimate contact with the wire. The rubber was so perished as to reveal the wire and was easily removed without tools. Leaving the perished insulation in place just wasn't an option as far as I was concerned.

The sleeving I used was of the 2mm PVC variety which comes in a range of colours. No doubt silicone or fabric based sleeving could be used if available. Of course it won't be authentic, because the sleeving is only a sliding fit on the wire.

I decided to replace the insulation because it was easier than fitting new wire. It's never easy unsoldering wires from a tag which has several wires and/or components soldered to it. In many cases the tag is buried under other wiring and components which will have to be removed first to gain access. I just unsolder the old wire at the easiest end.

When actually replacing wire on a chassis I always use solid tinned copper wire and PVC sleeving in any case. Wire such as battery connections is a different matter. Up to now I have always used new insulated wire for this, but in the set I'm restoring at the moment I just unsoldered the wire from the battery plugs, removed the old insulation, slid on new sleeving and resoldered the plugs.

Relative costs? I've no idea. I'm enjoying a hobby, not running a business and I have loads of sleeving in stock.

When resoldering the wire I heat sink it with a pair of thin nosed pliers which have an elastic band wound round the jaws to keep them closed. These are clamped to the wire close to the tag. This makes it less easy to melt the sleeving.

[stephanie]

Originally Posted by G4ILN

I decided to replace the insulation because it was easier than fitting new wire. It's never easy unsoldering wires from a tag which has several wires and/or components soldered to it.

Sometimes you can just wrap the wire around an existing component lead, close to the tag. Try to remove as much of the solder as possible...that way you don't leave a huge blob when you re-solder, and it's easy to wrap the wire around that existing joint.

As long as it's not flopping loose and is dressed in the same manner as the original wire was, it shouldn't be a problem.

Make sure the joint isn't "cold", I always give it a slight tug to make sure the solder grips.

[Phil G4SPZ]

Originally Posted by G4ILN

When resoldering the wire I heat sink it with a pair of thin nosed pliers which have an elastic band wound round the jaws to keep them closed. These are clamped to the wire close to the tag. This makes it less easy to melt the sleeving.

I am lucky enough to have a selection of straight and curved artery forceps of various sizes, which really make this task a dream. You can buy them from stalls at ham radio rallies and I've seen them at model railway exhibitions, if you can't scrounge one from your friendly doctor... or dentist!