# Main Pack Copper Tubing Cable Ends



## Ziggythewiz (May 16, 2010)

That looks pretty nice. I may need to try some as I don't want to order a few more lugs to make a couple new cables. I hate S&H.


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## piotrsko (Dec 9, 2007)

really cool, and probably cheap. 

The only issue I have : They are kinda thick at the bolt end, so unless the bolt is a close fit to the hole, you are structurally floppy. Probably not an issue. Any thoughts about crimping the ferrule or do you think you have enough cable area under the flat spot?


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## Ziggythewiz (May 16, 2010)

You could hammer the end as thin as you want. I'd only be concerned about the solder holding and even if you crimped it I don't think copper is strong enough to hold the crimp.

Ideal would be to crimp a stainless band over the copper.


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## swoozle (Nov 13, 2011)

It is a little thick, but there's not much to do about that. I bought longer studs and nuts to use so thread area should be adequate.

The benefit of using the vise is that the surfaces are flat and parallel. There's no "floppiness" once the bolt is torqued. Hammering would of course be different.

I solder after squeezing, so I don't think solder strength is an issue. All it really does is keep the strands from pulling out or being loose in the hole after drilling. And it seems to work quite well.


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## Ziggythewiz (May 16, 2010)

copper pipe isnt pure, it has some silver mixed in...but it's over 99% anyway.


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## dtbaker (Jan 5, 2008)

my concerns with this approach is the solder, enough really flat area for good contact with terminal, and possibly higher resistance of the tubing. 

solder in connections that will be carrying high amps is not a good idea as a slightly loose connection would quickly develop enough heat to maybe un-solder the joint... but you also have a mechanical 'crimp' for the flat end, so the solder is probably not needed anyway. I guess I would add hex crimp above the flat end instead; I bought a big crimper, and it only takes a minute.

is the flat area of the squished tubing really covering the terminal end? nice and flat, and with Noalox to prevent aluminum/copper oxidation?

it would be interesting to see if there is any measurable difference in resistance in a lug like this compared to a quality tinned crimp lug like a Magna-lug.


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## Ziggythewiz (May 16, 2010)

With a large load tester you could pump a few hundred amps through and check for temp changes...I doubt there'd be enough to tell though unless you can run it for a while.


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## DJBecker (Nov 3, 2010)

Copper loses thermal and electrical conductivity disproportional to the alloy percentage. A 90% copper alloy might only have 50% of the conductivity. Rated plumbing copper is surprisingly pure, over 99%, but other copper-looking stuff might not be a good choice.

It's important to crimp multi-strand cable enough to increase the intra-strand contact area, make a gas-tight seal, and carry the mechanical load. If crimped correctly, soldering just adds the risk of trapping corrosion-causing flux and concentrating the stress from flexing.

That's the "party line". But if your crimp isn't consistently perfect, solder-after-crimp is worth the down-sides.


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