In another thread, I spoke of some steps taken to put my Ruby back on the road, with it having languished at the back of the garage for a few years. Whilst assessing all the jobs that I aspire to carry out by means of improvement, the battery cables came under scrutiny. These are modern replacements, but manifestly not in the same league as the originals. When you've only got 6 volts to play with, the thickness of cables and the quality of terminations is obviously an important consideration.
Below is a picture of what I understand to be the factory original cable from the battery to the starter, condemned because the insulation has naturally broken down over time. The cable is of a decent thickness and the terminals at both ends appear to be soldered. I'm interested to know how others have tackled the business either of creating good quality battery cables, or if there are any recommended specialists who can supply a quality finished product to order. Many thanks.
I think you have grasped the key points already Ian - the bigger the better, don't skimp on cable. Ideally earth back to the battery rather than through the body. Some suppliers offer cable which is braided over pvc, which looks nice but can get a bit bulky.
I have made my own up in the past, as Chris suggests, with the appropriate quality cable. However, the most important thing to my mind was connecting the terminals to the cable. For this, I would visit my local radiator repair place who had the skill and kit to ensure a perfect soldered joint.
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Car type: 1934 Austin 7 AVH Van (in bits & incomplete!), 1936 Morris 8 Series I Tourer
29-01-2019, 07:03 PM (This post was last modified: 29-01-2019, 07:03 PM by Jeff Taylor.)
Ian M,
I've posted the following reply a number of times on the forum regarding battery / starter cable specification and suppliers of the cable and terminals:
Re having the correct size of battery / starter cables for 6v - the links below take you to suppliers of the correct specification battery / starter cable to buy for a 6v system.
Any decent auto electrician should be able to make up a cable to whatever spec you want. Jeff's specs look good. I would only crimp the terminals on, with the proper crimp tool that looks like a big set of bolt cutters. A proper crimped joint is much better than a poorly crimped and soldered one. After crimping you can cover the connection with heatshrink. Use the kind with glue inside it to get a waterproof connection.
If you solder them you're more likely to get corrosion in the joint from the fluxes (if you really do have to solder use proper electrical solder, not plumbers stuff that can have very acidic flux). Also the heat required will anneal the copper lug and copper wires making them softer and the point at which the solder wicks up the cable you get a stress point that can eventually break if the cable can move about. It's also hard to do without melting/affecting the insulation. Certain industries don't allow crimping and soldering of the same joint, notably space and aviation.
If you do earth to the chassis make sure you have a good earth from the engine to the chassis too, especially if it's a rubber mounted engine. How did they do that originally? Now I think of it I don't remember anything about an earth strap. I do know on MGBs they have one (a flexible braided strap) and if you forget it apparently the engine/starter can earth back through the throttle and choke cables!
I've used forklift battery charging cable. No idea of the spec. but it does the job with an added bonus of being very flexible and therefore manageable.
Second hand fork lift truck dealers are a good source.
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Car type: 1929 AD Tourer, 1930 Rosengart LR2, Rosengart LR4 Van 1938 APE Tourer (Opal)
Hi Ian M,
I agree with Jansens comments, have done a lot of Marine and Truck instillations and NO Soldering.
Main reason because a crimped joint spreads the individual strands and they make a much better contact .
were as a soldered joint can be what is termed a Dry joint ie the solder is not making a good contact either between the strands or the fitting leading to over heating.
The same reasoning can apply to NOT soldering wires going into junction boxes .
I was always told (when working as an electronics technician) that the reason you don't use soldered/tinned wires under screw terminals is because the solder is soft and over time it 'creeps' and the connection will come loose. Not sure how accurate that it but definitely at a holiday job I had doing stuff for a military application years ago they were strict on what we could and couldn't do and crimped and screwed connections couldn't be tinned or soldered.
Saying all this I think a decently soldered connection will work perfectly fine in an Austin 7 even if not 'technically' correct. Practically it should work fine if the solder joint isn't a dry one as Colin says.
With ready made leads I find it can be hard to find black ones these days. For some reason a lot seem to be blue! The ones I had made weren't much more expensive than buying ready made ones. It's a quick job for someone with the right tools and you get the exact length you need.
30-01-2019, 09:00 AM (This post was last modified: 30-01-2019, 09:02 AM by Duncan Grimmond.)
Another disadvantage of soldering is that capillary action with molten solder makes the flexible rigid at a point where it may well be subject to mechanical stress. This can lead (eventually) to a fracture just beside the soldered section, particularly in cars which have high vibration and subsequent loss of loose parts...
A hefty crimp is a far more appropriate method.
