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I need to get some heat shrink tubing around something that is too big on the ends for it to slide over. Is it possible to cut the heat shrink along it's length and somehow reattach it before applying heat to get it to shrink?

If you have any alternative suggestions I need the material to be transparent.

JRE
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stbtra
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7 Answers7

35

Actually it is possible. I did it myself.

1) You have to cut the shrink tube lengthwise.

2) Wrap it around the part where you want to apply.

3) Apply superglue to the separated part and reattach them (it is not necessary to attach the ends exactly at cut part, you can attach them as you desire).

4) Apply Heat and VOILA it works.

Please do some experiment before you commence this procedure.

P.S - I know I am 4 years late. Just wanted to share.

Arin Chakraborty
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12

So happy to see the superglue solution posted by Arin Chakraborty. I have a 3/16-inch diameter cable coming out from a box and the sheathing around it is broken but I absolutely cannot cut it. I have been searching for a while for a solution.

Here is what worked:

  1. I chose a 1/2 inch diameter heat shrink and cut it open lengthwise.
  2. Removed excess so the circumference wrapped loosely around my cable with an overlap of about 1/8 inch.
  3. Applied a thin line of Krazy Glue on the overlap area and allowed the bond to form to reclose the heat shrink to wrap around the cable loosely. The idea is to keep the glue line thin because the glued area will not shrink under heat.
  4. Allowed time (a few minutes) for seal to cure.
  5. Applied heat as usual and it worked perfectly.
Null
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chmak
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11

How about cutting the tubing in spiral instead of lengthwise. I am tempted to try that as I have just regular heat shrink tubing (not 4:1) and I want to heat shrink my iphone cable and connector. Another option would be to add something under the tubing like a spring wrapped around the cable. That will give it some thickness.

Nitin
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    The spiral cut worked! It took a few tries though. The cut has to be clean, and at a fairly steep angle. Heat the tubing evenly. It will start to uncurl rapidly, then slowly curl back together. It is similar to how Shrinky Dinks [curl then uncurl in the oven](https://youtu.be/hXiEqJfg-pM?t=126). Done properly, the cut edges almost join themselves together. This won't be watertight though. – Moby Disk Jun 24 '16 at 04:03
10

My alternate suggestion would be to use a self-annealing (self-amalgamating, self-fusing) tape.

Your local electrical supply store should have some - it is a step up from regular electrician tape. It is usually similar to double-sided tape, in that both sides have "something" on them, and that as you wrap it, and stretch it a bit, it binds with itself.

Here is one specific example and a hopefully long-lived link at 3M, one manufacturer of the stuff (not used that specific brand, but mine is from a very local supplier)

Good Luck

sdg
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  • That looks like it should do the trick, only down side is it seems a bit expensive. Thanks! – stbtra Nov 30 '10 at 21:43
  • This stuff looks great but is that really 40 bucks a roll? http://www.amazon.com/3M-Electrical-15603-Scotch-Siliconerubber/dp/B0018LC5QM/ref=sr_1_cc_2?s=aps&ie=UTF8&qid=1340039232&sr=1-2-catcorr&keywords=Scotch%C2%AE+70+Self-Fusing+Silicone+Rubber+Electrical+Tape – Brian Jun 18 '12 at 17:10
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    @brian, I found some cheaper ($9 for a 10 foot (~3m) roll) at my local hardware store ([Home Depot](http://www.homedepot.ca/product/tape-silicone-self-sealing-10-1-cd/963554), if it matters). Might be worth investigating the electrical isle at one of those! Edit: Woops, I just noticed how old this post is... How did I end up here? – Mewa May 27 '15 at 21:26
  • @Mewa What I love is composing an excellent answer only to look at dates just before I post and realize it is irrelevant. – StainlessSteelRat May 28 '15 at 01:08
  • Unfortuantely, a decade later, neither of your links were as long-lived as hoped – Patronics Feb 10 '21 at 08:19
  • [Nashua Stretch and Seal Self-Fusing Silicone Tape](https://www.homedepot.com/p/Nashua-Tape-1-in-x-3-33-yd-Stretch-and-Seal-Self-Fusing-Silicone-Tape-in-Clear-1743079/203534911) – Rufus L Jul 16 '21 at 23:57
5

You can sometimes get away with cutting it if your heatshrink has adhesive, but this generally isn't a good method. Ideally you want to put the heatshrink on before the connector goes on. If you haven't done this you can get away with getting larger heatshrink if it is able to shrink enough.

Your other option is to use electrical tape or heatshrink tape.

EDIT:

seen this actioned successfully @ Ex-Work; the 4:1 adhesive lined heatshrink was lashed snugly on the outside of the joint with lacing cord (using the correct tieoffs) then shrunk down. As the slit tube shrinks, it's thickness increases. This made it visibly push back against the lacing cord & made a really sound job of it. Hope that helps! :-j

teknojon
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Kellenjb
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4

Cutting won't work. You can get heatshrink with shrink ratio up to about 4:1, but possibly not transparent.

mikeselectricstuff
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2

The method described in this video first stretches the heat-shrink tube to fit over the connector, which doesn't seem to affect its shrinking ability.

Comments to the video suggest that using needle-nose pliers and/or chopsticks works best to stretch the heat-shrink tube.

Voltage Spike
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Brecht Machiels
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