50mm Cable and clamps

[geekygrilli]

Hi there

Just wondering if anyone has any 'spare' 50mm (sq mm) for sale?

I need about 12m for thh completion of my EV. I also require round terminal clamps, +ve and -ve for the above cable.

Any help would be much appreciated.

Best regards

Christopher

[ChrisB]

Good place for 50mm is a local welding company

ChrisB

[geekygrilli]

I did just that, and got it for £3.50 a metre which is extrodinarily cheap...one step closer to completion. Now just need teh clamps and I'm all done!

Thanks

[EVguru]

I buy my cable from Farnell.

50mm2 Roebuck cable £2.39 per metre +vat

Order code; 092186

For quality and reliability you really can't beat these Quickcable battery terminals;

http://www.evparts.com/shopping/product ... ct_id=1671
http://www.evparts.com/shopping/product ... ct_id=1673

1/0 American wire gauge is very close to 50mm2 and they work perfectly.

Sadly you can't seem to get them in the UK, but with the dollar rate they're pretty cheap.

There's a whole range at EVparts.com

You need a BIG pair of crimps, but I have a pair I'll lend out for the cost of posting.

A cheaper solution and a good bit of recycling is to get hold of old crimped clamps, cut the crimp off and put on a new one.

I've done this by buying butt splices (Farnell again), cutting them in half and silver soldering them to the battery terminals.

[ChrisB]

Handy for peeps to know you've got a set of big crimpers Paul

One other option if people are looking at putting large crimps on big cable is to go to electrical wholesalers, like CEF or AEC or Newey & Eyre etc and buy your crimps from them as they will generally let you hire a good set of crimpers for the weekend for free or at the very least for a basic fee. Another option is if they wont lend them to you as they have never seen you before, then take you cable ready cut cable to them and they or you can crimp the ends on while your there

Must admit Paul as you say, with the £/$ looking so good its very tempting to buy in loads of goodies , only trouble is the dam import duties

ChrisB

[geekygrilli]

Ah, thought I'd got a bargain - compared to other prices I'd been quoted (up to £6.50 a metre)
.
Never mind, i've got it now!

Search for clamps goes on (in England!)

Thanks for your help guys.

[EVguru]

Handy for peeps to know you've got a set of big crimpers Paul

Actually I've got two sets!

One set will go up to 50mm2. They're suitable for the ordinary lugs, like the Davico ones in the Farnell catalogue.

I've also got a set of 3 foot long ones which will do the heavy duty American battery terminals and heavy duty lugs. These have AWG dies and I keep meaning to get a metric die set for them as well.

I really haven't seen good quality CRIMP battery clamp terminals in the UK and would definitely NOT recommend the solder type.

At a pinch I've used good quality terminals with screws that clamp down into the wire. I use these with a copper tube slipped over the wire. Otherwise you just end up cutting through the strands. Even then I'd only use them on relatively low voltage and current systems.

The other solution is to get the battery clamps that have a stud or bolt so you can attatch a cable with a lug. You can also put a lug under the clamp bolt, but it's not a very nice solution.

Watch out for cheap terminals in either plain brass (often brittle and they corrode badly) or terminals cast out of aluminium or zinc alloys. These are total junk and can actually catch fire and water makes them burn more fiercely! Don't use any terminal that claims to fit both positive and negative posts.

I've seen a lot of melted battery terminals, burnt cables, and even vehicle fires caused by poor connections. It's not hard to do it right first time.

[MalcolmB]

I really haven't seen good quality CRIMP battery clamp terminals in the UK and would definitely NOT recommend the solder type.

Just wondered why you wouldn't recommend soldering terminals? I used cable terminals from here http://cse-distributors.co.uk/cabmgmt/coppertube.htm, and soldered them to make up cables for my motorcycle. It took a couple of attempts on a piece of spare cable to get the technique right, but they seem very reliable and don't get warm at all in operation.

Oops, sorry, just realised you're looking for clamps, not terminals. Maybe these would be more useful http://workshoponline.co.uk/search.asp?types=yes&type=Battery+Terminals+%3E+Tinned+Brass

[geekygrilli]

Thanks again...

I've just ordered loads of bits from here:

http://www.vehicle-wiring-products.co.u ... TTCON.html

If the clamps turn out to be rubbish i'll just replace them later. i just want to get my car up and running for the moment!

Just gone over my £2000 budget (

[EVguru]

Just wondered why you wouldn't recommend soldering terminals?

Soldering is tricky. It takes a lot more skill and practice to make a good soldered joint compared to a crimp. You really need a temperature controlled solder pot to do it right. You don't want the insulation melting back, or the solder wicking up the cable and losing flexability. If you get the temperature wrong the solder can crystalise and you get a brittle joint. It's also difficult to clean the flux off.

Worst of all is the failure mode. A bad crimp has higher resistance from the start and will get hot in use, but is unlikely to actually fail without warning. If a solder joint gets too hot it spits the solder out and now you have a totally failed joint. I used to see this quite often in the Highschool race series in the US. A good crimp is a cold weld and the British Standard test for a good crimp is the pull out force. I've seen many more bad soldered joints than crimps and the crimps showed up early. Crimping is better and safer to do. It's only downside is the cost of the tooling and that can often be borrowed.

I've just ordered loads of bits from here:

http://www.vehicle-wiring-product...k/V ... TTCON.html

If the clamps turn out to be rubbish i'll just replace them later. i just want to get my car up and running for the moment!

Assuming that these terminals are maleable brass or copper, they themselves should be OK. The wire clamp screws WILL just cut through the fine strands of welding wire unless you protect them. In the past I've used a length of copper pipe that's a tight fit over the cable and file the ends of the clamp screws to a domed shape. You could also SILVER solder a butt splice onto the terminals to convert them to crimps. Actually if you put a butt splice on the cable and a bit of copper bar into the other end and clamp down onto both, that would be Ok.