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Electronics => Beginners => Topic started by: josr on September 04, 2020, 07:14:15 pm

Title: Easiest way to shrink heat crimping tube?
Post by: josr on September 04, 2020, 07:14:15 pm
Hi,

What is the easiest way to crimp heat crimping tube (best crimp and least change of damaging plastic connector or wire isolation)

I tried with the tip of the soldering iron but this does not give a full crimp.

I am looking for tips using basic electronics/household tools (eg not a hot air gun, but what about a hair dryer?)

Thanks Jos
 

Title: Re: Easiest way to shrink heat crimping tube?
Post by: capt bullshot on September 04, 2020, 07:22:59 pm
A lighter usually does a good job for me, if the hot air tool isn't readily available. A hair dryer isn't hot enough.
Title: Re: Easiest way to shrink heat crimping tube?
Post by: Benta on September 04, 2020, 07:55:13 pm
Yep, 99 ct lighter from the local discount supermarket.

Title: Re: Easiest way to shrink heat crimping tube?
Post by: Gyro on September 04, 2020, 09:48:28 pm
A lighter usually does a good job for me, if the hot air tool isn't readily available. A hair dryer isn't hot enough.

Actually, I modified my wife's old hair curling wand (fan and heater at one end, perforated aluminium tube with bristles at the other). I unscrewed and removed the aluminium tube assembly, and fitted a bit of protective mesh over the resulting hole in front of the element. It heat shrinks nicely, just the right temperature, with no danger of burning PVC insulation.

It saves me having to keep adjusting the temperature and airflow of my hot-air gun.
Title: Re: Easiest way to shrink heat crimping tube?
Post by: Brumby on September 04, 2020, 11:49:54 pm
The $1 lighter will work - but much care is needed.

I got myself a really cheap soldering/hot air station off eBay.  The soldering iron is crap, but the hot air is brilliant for heat shrink.  Risk is practically zero.  Results are optimal.
Title: Re: Easiest way to shrink heat crimping tube?
Post by: Renate on September 05, 2020, 12:46:58 am
I hate to see someone use a lighter in a professional setting.
You can get an NTE hot air gun (model HG-300D) for $20.
I use the lower setting.
https://www.nteinc.com/heat-guns.php (https://www.nteinc.com/heat-guns.php)
Title: Re: Easiest way to shrink heat crimping tube?
Post by: FriedMule on September 05, 2020, 12:58:18 am
Yes you can use a lighter, but as Renate, do I think you'll be much better off with a heat gun.
The lighter is a bit like using a Pipe Wrench as a hammer, it can be done but you may risk damage and the result will never be as good.
Title: Re: Easiest way to shrink heat crimping tube?
Post by: tkamiya on September 05, 2020, 02:50:43 am
I guess you mean heat SHRINK tubing?

There are many ways to do it and I've done them all.  The easiest and not too costly is to actually use proper tools.  You can get a hot air gun with small nozzle.  You can buy one from China for less than $50.  Ones with too big of a nozzle will end up melting connector, etc.  Hair dryer and lighter will require finesse.  If you are going to be doing this more than few times, I really recommend getting a small heat gun.
Title: Re: Easiest way to shrink heat crimping tube?
Post by: Jwillis on September 05, 2020, 04:36:16 am
Hi,

What is the easiest way to crimp heat crimping tube (best crimp and least change of damaging plastic connector or wire isolation)

I tried with the tip of the soldering iron but this does not give a full crimp.

I am looking for tips using basic electronics/household tools (eg not a hot air gun, but what about a hair dryer?)

Thanks Jos
 

Are you talking about the insulated heat shrink connectors? You would use the same as non heat shrink connectors for crimping.  I avoid lighters unless I have no other option. Lighters can burn which  hardens the plastic making it brittle. Just be careful not to scorch the insulation.
Title: Re: Easiest way to shrink heat crimping tube?
Post by: pwlps on September 09, 2020, 08:22:44 pm

I tried with the tip of the soldering iron but this does not give a full crimp.
 

I actually do it often with a soldering iron, but touching with its wider body a few cm from the tip and set a bit lower temperature (the minimum shrinking temperature depends on the material but is relatively low compared to temperatures used for soldering, e.g. for common polyolein tubes it is around 100°C). I gently slide it over the tube at different angular positions until it shrinks everywhere. That said if you need a perfect roundness then you need a hot air gun.
Title: Re: Easiest way to shrink heat crimping tube?
Post by: Electro Fan on September 09, 2020, 10:26:31 pm
looks good, variable speed, nozzle adapters...

https://www.amazon.com/SEEKONE-Heat-Gun-Hot-Air/dp/B078S5QMFG/ref=sr_1_5?dchild=1&keywords=heat+shrink+gun&qid=1599690280&sr=8-5 (https://www.amazon.com/SEEKONE-Heat-Gun-Hot-Air/dp/B078S5QMFG/ref=sr_1_5?dchild=1&keywords=heat+shrink+gun&qid=1599690280&sr=8-5)
Title: Re: Easiest way to shrink heat crimping tube?
Post by: Siwastaja on September 10, 2020, 07:37:13 am
Heat shrink. Crimping is a different thing, but close enough in context to cause some real confusion.

Cheap Chinese temperature-regulated hot-air soldering/desoldering guns. Fix failed protective earth connections as the very first step to make them less lethal. Always use RCDs for protection in any case. Otherwise than that, mine works very well. Adjust for maximum air flow pressure and approx. 140-150 degC for quick and effective shrinking and no insulation damage.
Title: Re: Easiest way to shrink heat crimping tube?
Post by: Zero999 on September 10, 2020, 12:16:37 pm
Heat shrink. Crimping is a different thing, but close enough in context to cause some real confusion.

Cheap Chinese temperature-regulated hot-air soldering/desoldering guns. Fix failed protective earth connections as the very first step to make them less lethal. Always use RCDs for protection in any case. Otherwise than that, mine works very well. Adjust for maximum air flow pressure and approx. 140-150 degC for quick and effective shrinking and no insulation damage.
It's still ambiguous. I thought the original poster was on about heat shrink solder connectors, which need much higher temperatures than ordinary heat shrink sleeving.

I prefer to use wire with high temperature insulation, i.e. PTFE or silocone, rather than PVC whenever possible. It's more expensive, but much easier to solder.
Title: Re: Easiest way to shrink heat crimping tube?
Post by: dnwheeler on September 11, 2020, 08:09:59 pm
Check the kitchen for a Crème Brûlée torch.
Title: Re: Easiest way to shrink heat crimping tube?
Post by: SilverSolder on September 11, 2020, 08:13:13 pm

Get a heat gun with adjustable temperature.  Use the reducing nozzle to aim the heat more precisely.  Set it to the lowest temperature that shrinks the material reliably.  This will be the fastest/safest way, and should not cost very much.