Head shrink stuff....

[rambo1969]

Anyone used the heat shrink stuff which you put on a cable when you have connected a new terminal?

[snowtracdave]

I bought a pack of assorted bits a long time ago from Tandy (which shows you how long ago it was) . Used a couple of bits with varying success and now seem to have lost the rest......at least the last time I tried to find a bit ...........

 

Think I used a hair dryer to shrink the tube , or maybe hot air stripper on a low setting . Worked ok anyway , just a bit fiddly .

[Richard Farrant]

Yes Rambo. Good stuff, there is even a woven one which looks like black cloth, it shrinks right down and looks good on harnesses. I use a hot air gun.

[Glynn]

Yeah its good stuff but get the right size for the cable. You can shrink it with a hot air gun or by rubbing it with a soldering iron but be careful not to burn through . Different makes have different shrink rates, And lots of colours.

[rambo1969]

Could I use a hair dryer?

[Johnny]

Very useful stuff. Cut the length you need, slip it over the cable(s) then attach the terminal. Slip the heat shrink down to where it's needed and heat to shrink it into place.

It doesn't need much heat to shrink it, I use a hot air gun or a cigarette lighter. A hairdrier should work I'd have thought.

These places sell it by the meter at very reasonable prices.....

http://www.vehicle-wiring-products.eu/VWP-onlinestore/sleeving/heatshrink.php

http://www.autoelectricsupplies.co.uk/product/339

Edited January 8, 2010 by Johnny

[Stone]

Heatshrink is absolutely brilliant stuff! I use it all the time. Always use a hot air gun to shrink it (it leaves a plasticky residue on soldering irons which is a pig to clean off) - you can use a cigarette lighter if you're careful but beware of flammable stuff nearby; it will also leave a sooty burn mark on lighter colours of heatshrink.

 

If you overheat it the strength is seriously diminished and it will usually split - once split it never lasts long. Keep the heat moving and you'll be fine.

 

Pick the right diameter for what you're doing (you can build it up in layers if you have several smaller sizes) - it makes fantastic strain relief, but I usually use it to cover the gap between cable and connector. You can get a type lined with a layer of hot-melt glue which melts and conforms when you shrink the sleeving, this is good for light-duty waterproofing.

 

Lastly don't forget to put the sleeving on before soldering up the connectors!

 

Stone

[philb]

What Stone said, plus:

 

I nearly always use the glue lined version. As well as being really good for insulating in-line cable joints it bonds to metal quite well and provides good strain relief at the entry to junction boxes etc..

 

Whatever the joint, make sure there are no prickly bits sticking out before the heat-shrink is applied, or it can poke through.

 

We use it at work for some fairly serious water-proofing applications (many days total immersion) and it does well.

 

And another thing, it's good for sealing/reinforcing damaged Bowden cable sheaths.

[Stone]

Not seen that fabric stuff before - all the harnesses we make at work (military avionics) use the standard rubbery stuff, but it looks good!

 

You can also get heatshrink pre-printed with different legends; we used to have a set of drawers containing tiny snippets each with an individual letter or numeral printed on. You would assemble them around your cable in the correct order, shrink them, then apply a slightly larger piece of clear heatshrink over the top to stop it rubbing off. Great for permanent labelling of what each section of a loom does, and withstands dirt and grime very well. Especially for military stuff where all the wires tend to be the same colour it's a lifesaver!

 

Stone

[listerdiesel]

There are two main types:

 

Polyolefin and PVC.

 

Polyolefin is heavier-duty and thicker, costs more but is more durable.

 

PVC is thinner, cheaper and more readily available.

 

Heat-guns are recommended as hair dryers take forever and you can end up getting the underlying parts overheated.

 

We buy reels of the stuff and keep most electrical colours, have also got some larger sizes that we used to use on battery packs, up to about 3" or 4" diameter in PVC. We do have some large Polyolefin but it's awfully expensive to buy even a small quantity of, so we keep that for a specific job on the railways.

 

Peter

[Gordon_M]

I use it on all my electrics, but don't buy enough for economies of scale to kick in. E-Bay is your friend, or Halfords if you are rich.

 

I work mostly on 1939-41 Dodge stuff, and I long ago realised that the original electrical cables and fittings were super-solid, heavy gauge, high quality - the only problem is that the insulation tends to have gone over the past 70 years.

 

I'll strip a whole truck, gut the dash, pull out the chassis harness, and assess each wire individually before deciding what to do with it. I'll keep any special wires, like heavy duty battery / ammeter cabling, and maybe heat-shink new insulation over the lot. Anything non specific I'll check both ends and any insulation gaps in between then put it on the pile for use - typically I'll cut it to use one end and a specific length, with new heat shrink and one new termination, or remove and re-solder the original termination to the required length.

 

Complete visible loom sections get wrapped in that hockey-puck tape, leaving just an inch or two of the original fabric wrapping for effect.

Edited January 16, 2010 by Gordon_M