Why 50% of All Crimp Electric Connections Fail - One Trick Fixes It

[StarTech]

A properly crimped terminal is what is called gas tight meaning the metal of the terminal is compressed hard enough on the wire that oxygen molecules can't get between the terminal and wire. If not crimped properly oxygen can penetrate and oxidize the metals causing corrosion. 99% of DIY crimps fail because wrong size terminal or wrong tool doesn't make a proper mechanical gas tight crimp.

If that is the case then 99.9% of all factory crimps should also fail. This why No Ox should be use when crimping the terminal then heat shrink applied.

Here I use a lot of open barrel terminal and they are only near 95% sealed unless I use heat shrink tubing. Even the battery cable that are hydraulically crimped still need the heat shrink applied. And my battery cable can crimp so tightly that the stranded wires become a solid mass but where the cable meets the cable lug the insulation is still not fully sealed unless heat shrink is applied.

The main with terminals is they are not crimped properly.

 

[PTmowerMech]

Anyone ever use that battery post red coating? It's too thin to be paint. I was wondering if spraying that on a wire connection would be beneficial. Spray it on, then use heat shrink over it.

 

[bertsmobile1]

A properly crimped terminal is what is called gas tight meaning the metal of the terminal is compressed hard enough on the wire that oxygen molecules can't get between the terminal and wire. If not crimped properly oxygen can penetrate and oxidize the metals causing corrosion. 99% of DIY crimps fail because wrong size terminal or wrong tool doesn't make a proper mechanical gas tight crimp.

You can never ever crimp that tight even with a a hydraulic press
That is an old wives tale
FWIW I rarely ever use those cheap internal terminals
I use proper automative ones where the sides of the terminal penetrate the insulation so stop it from pulling back as it gets ols & shrinks leaving exposed wire t short out or work harden & break
So when using them you crimp the open end with a crimper that has a W shaped anvil on one side
The crap he was using might be OK for indoors but not on a mower .

 

[GearHead36]

To me, a crimp is no good unless you can slice it apart and see a solid blob of copper. Always like to add a dab of solder to the exposed copper on the connector for a 1-2 punch.

I prefer soldering and marine grade heat shrinking with the adhesive goo inside it. Depends on what tools I have access to.

Same here. Or... I'll opt for a solder terminals. Soldering doesn't require that I have an expensive crimper and the exact correct jaws. If soldered properly, solder is just as good as crimping. It was the airline manufacturing industry that started making connections with crimping. They found that it was much cheaper to train assemblers to crimp vs solder. It wasn't because crimping was better.

 

[Hammermechanicman]

You can never ever crimp that tight even with a a hydraulic press
That is an old wives tale
FWIW I rarely ever use those cheap internal terminals
I use proper automative ones where the sides of the terminal penetrate the insulation so stop it from pulling back as it gets ols & shrinks leaving exposed wire t short out or work harden & break
So when using them you crimp the open end with a crimper that has a W shaped anvil on one side
The crap he was using might be OK for indoors but not on a mower .

I guess I was wrong.

https://www.panduit.com/content/dam/panduit/en/products/media/5/55/455/7455/110187455.pdf

What is a GOOD crimp connection? - SM Contact EN

| EN

smcontact.eu

Is gas tightness possible with ferrules?

For a gas-tight connection, the conductor and connector must be pressed together so tightly that there are absolutely no more gaps. With wire ferrules, such a firm connection is generally not possible

knowledge.knipex.com

Gas tight

What does gas-tight mean? As a gas-tight connection is one where the conductors and connectors are so tightly deformed and compressed together that there a...

www.rennsteig.us

A well-engineered and well-executed crimp is designed to be gas-tight, which prevents oxygen and moisture from reaching the metals (which are often different metals) and causing corrosion. Because no alloy is used (as in solder) the joint is mechanically stronger.

 

[bertsmobile1]

I guess I was wrong.

https://www.panduit.com/content/dam/panduit/en/products/media/5/55/455/7455/110187455.pdf

What is a GOOD crimp connection? - SM Contact EN

| EN

smcontact.eu

Is gas tightness possible with ferrules?

For a gas-tight connection, the conductor and connector must be pressed together so tightly that there are absolutely no more gaps. With wire ferrules, such a firm connection is generally not possible

knowledge.knipex.com

Gas tight

What does gas-tight mean? As a gas-tight connection is one where the conductors and connectors are so tightly deformed and compressed together that there a...

www.rennsteig.us

A well-engineered and well-executed crimp is designed to be gas-tight, which prevents oxygen and moisture from reaching the metals (which are often different metals) and causing corrosion. Because no alloy is used (as in solder) the joint is mechanically stronger.

Rubbish
If you think you can compress & deform all of the strands of the wires so they become as if a single piece of copper with nothing but your hands an a 5" leverage advantage from a hand crimper then you are delusional or perhaps big Arnie in his prime .
With a powered hydraulic press perhaps but there is no way that crimp will be air tight

 

[Hammermechanicman]

I use a hydraulic crimper for battery terminals

Amazon.com

I use a ratchet crimper for smaller terminals

Shopping

I repair connections all the time where the DIY guy used the shitty pliers to make a shitty crimp

For the last 20+ years I have run a mower repair business and an audio/video install business. I have made literally thousands of crimp and solder connections. Haven't had a call back for a failed connection.

 

[PTmowerMech]

I use a hydraulic crimper for battery terminals

I use a hammer and an old long socket.

 

[StarTech]

I used to use one these for the cable lugs.

But I now use one these.