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I f**ked up - cut power cable running to battery too short


IM-32-FK
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I recently bought a new battery and thought at the same time to change the battery terminal clamps so it can look neat. I tried to pull off the wire off the existing clamp as hard as I could but it just wouldn’t come out so I had to cut it. The negative wire cleared it, just barely but the positive wire is too short. I mean I can get it sitting inside the terminal clamp but with very little exposed wire and the the wire is stretched to its maximum reach so there is a lot of tension on it, and because of such tension I worry it might come off the clamp during driving and potentially leave me in dangerous situation.

 

what are my options here? If it were the negative wire I can replace the whole wire because it grounds to a point on the chassis between the battery and the engine. But I had a look and the positive is connected right into the loom so it can’t be replaced like that. My car is r34 gtt

 

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2 minutes ago, KiwiRS4T said:

You'll have to buy some more and join it - with solder.

Do you know what gauge the cable is? 8 maybe? Also soldering thick wire, only the outer parts can get soldered and not the inner wires

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There are big tube like crimps and a big [looks like a set of bolt cutters] crimping tool.  

Me, I'd replace the whole lead, but you can - if you're stuck - use some resin filled heat shrink and one of the big crimps and add some extra wire for length.  All doable, and you can hire the crimping tool.  

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34 minutes ago, tridentt150v said:

There are big tube like crimps and a big [looks like a set of bolt cutters] crimping tool.  

Me, I'd replace the whole lead, but you can - if you're stuck - use some resin filled heat shrink and one of the big crimps and add some extra wire for length.  All doable, and you can hire the crimping tool.  

Ok I’d like to replace the whole lead, from what point of the loom can you take off the existing wire and put in the new one? It’s a r34 gtt thanks 

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2 minutes ago, GTSBoy said:

FFS! It's just wire.

?

I don’t mind changing it, I was just asking if the positive wire can we taken off a certain point and replaced or would I need a whole new loom.

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I'm sure an Auto Elec can extend it for not much money. They would have the correct guage wire and the correct crimp terminals. 
If I recall correctly it's actually the terminals that cost decent money. 

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On 6/22/2020 at 12:55 PM, Dose Pipe Sutututu said:

No to solder in a high vibration environment.

That's not the reason. Plenty of things are soldered in automotive and industrial environments. Soldering heavy gauge wire is not a good idea because the heavy copper sinks away the heat very quickly and if you get the solder to wet, you end up with a giant clump of soldered wire.

I have one of these tools to crimp heavy wire:

th?id=OIP.uhuQnQzXYTVSH5HmcFQw0wHaHa%26p

 

Ive had to do the battery terminals before because there's been a few different battery terminal layouts that needed a longer terminal wire.

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23 hours ago, Murray_Calavera said:

Can you give me some examples of when the OEM or professional motorsport teams are using solder?

Errrr, have you ever opened any electronics in the history of ever? ECUs, controllers and even PCBs in sensors have soldered connections, and they are all subject to vibration. I mean, this is a thoroughly engineered topic that goes well beyond automotive. Vibration testing methods is an aspect of electrical engineering after all.

Solder itself isn't the problem. When you make a solid solder connection you form a mechanical system that has a resonant frequency. As long as there is sufficient strain relief and damping of the vibration, it's not going to magically break off.

I think my post is pretty clear about the scope of what to use where.

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1 hour ago, zoomzoom said:

Errrr, have you ever opened any electronics in the history of ever? ECUs, controllers and even PCBs in sensors have soldered connections, and they are all subject to vibration. I mean, this is a thoroughly engineered topic that goes well beyond automotive. Vibration testing methods is an aspect of electrical engineering after all.

Solder itself isn't the problem. When you make a solid solder connection you form a mechanical system that has a resonant frequency. As long as there is sufficient strain relief and damping of the vibration, it's not going to magically break off.

I think my post is pretty clear about the scope of what to use where.

Seems like we are talking about different things here. 

The OP was talking about terminating a cable. 

Dose and I are suggesting that crimping the cable would be the ideal way to terminate a cable. 

When I asked about examples of using solder, I was talking about in the same scenario. So for example, the connector into the back of my ECU has a crimped pin, wire, into crimped pins into a sensor. There is no solder there. 

If you look at a mil-spec racing harness, there is no solder there. Plenty of crimps, Raychem DR25, Raychem SCL, Raychem ES, epoxy resin, molded boots, probably some Kapton tape and no solder. 

I don't care if my microwave has solder in it. We were talking about terminating a wire, that is in a car, that is subject to vibration and a potentially harsh environment. 

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I think the main thing to remember is that when trying to "butt" join a (large diameter) wire, if someone was to propose splicing it together and then flooding it with solder, then it is bound to fail. Solder is NOT a mechanical joint. It is an electrical joint. It's mechanical properties are far inferior than its electrical properties, and joints that rely solely on solder (such as components on circuit boards, etc) do not have very tough mechanical mounting requirements. Devices that do have tougher mechanical mounting requirements will have twisted tags poking through the board as additional/primary mechanical mount points (or big fat solder pads with the back of the package stuck down, for mech and heatsinking).

Big wires get crimped. End of story.

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