RogerMayne
Member
The reason that you should use crimp connection as opposed to solder on battery leads is due to the possibility of heat under load melting the solder
soldering a battery lead
- Thread starter sarabande
- Start date
elton
Well-known member
If a connection becomes hot enough to melt solder under load, then you're better off if it does melt and breaks the connection. A good soldered connection should offer little more (or no more) resistance in the circuit than any other part of the wiring, so there's no reason why it should become any hotter.
Otherwise you're in a situation where the cable insulation is going to combust, or something else is going to fry. Think of it as a fuse of last resort perhaps?
BrendanS
Well-known member
given that most people won't have access to the correct ratchet crimpers and crimps to cope adequately with all circumstances, I'd go for a reasonably good crimp, with a minimum of solder. If I had the crimping tools to cope, I'd go for a straight crimp.
Some thought provoking stuff in these links
My personal favourite is this one, which includes the comment
"Best choice is to buy the high $$$$ crimping tool for every connector you use, and use no solder.
Good choice is to crimp each connector with the $10 crimp tool, and solder the connection, using solder sparingly.
Worst choice is to use the $10 crimp tool alone."
http://fsae.com/eve/forums/a/tpc/f/125607348/m/53010954411
http://www.virginiawind.com/tips/060801_02.asp
http://www.mail-archive.com/lancair.list@olsusa.com/msg10019.html
and as one of those links says, if you don't have strain relief on the connection, it's more likely to fail, no matter what technique you use.
Some thought provoking stuff in these links
My personal favourite is this one, which includes the comment
"Best choice is to buy the high $$$$ crimping tool for every connector you use, and use no solder.
Good choice is to crimp each connector with the $10 crimp tool, and solder the connection, using solder sparingly.
Worst choice is to use the $10 crimp tool alone."
http://fsae.com/eve/forums/a/tpc/f/125607348/m/53010954411
http://www.virginiawind.com/tips/060801_02.asp
http://www.mail-archive.com/lancair.list@olsusa.com/msg10019.html
and as one of those links says, if you don't have strain relief on the connection, it's more likely to fail, no matter what technique you use.
elton
Well-known member
There should be no need to use both methods if you've done one or other correctly. If you've done a bad crimp then bad soldering isn't going to help.
colvic987
Active member
my poper battery cable crimpers (makes a hexagonal crimp in the terminal)
Hi shaun, have you got a link to the type of crimpers you use, as i have got to go thru this procedure, during the winter months to redesign and replace my battery leads as i have to fit a ground plate and fit an ammeter to the system.. i prefer to do this on the boat and not have to take the leads to an auto electrician to get the lugs crimped on...
Hi shaun, have you got a link to the type of crimpers you use, as i have got to go thru this procedure, during the winter months to redesign and replace my battery leads as i have to fit a ground plate and fit an ammeter to the system.. i prefer to do this on the boat and not have to take the leads to an auto electrician to get the lugs crimped on...
JohnTH
New member
Oh well, here goes. A solder pot to "dunk" the end of the wire in, the insulation will not go up in flames but the copper will come out "tinned" A self tapper in the hole will stop solder gushing out of the connection. Using a steady hand with the blowlamp, feed solder in to the cavity of the terminal until there is a molten mass of solder. Now this is the clever bit, (well it is if you can make it work!) enter the tinned end of the cable into the cavity. Job done ! !
Of course I have made this sound a simple process (and it is, even I can do it) however, as with most things, it takes practice to get temperatures etc correct.
Solder Vs Crimp..... not qualified to say, but I like solder, so there.
73s de
Johnth
Of course I have made this sound a simple process (and it is, even I can do it) however, as with most things, it takes practice to get temperatures etc correct.
Solder Vs Crimp..... not qualified to say, but I like solder, so there.
73s de
Johnth
ean_p
Well-known member
just a couple of personal observations on this subject. until a couple of years ago I used to have the responsibility for maintaining about 300-400k squids worth of lead acid traction batteries in some pretty awful operating conditions. the batteries supplied by different manufacturer's had different qualities. The top quality(chloride) always had all soldered joints, between cells and on all leads and connectors. The low end of quality (Varta) always had crimped and bolted fittings on all connections. i always found in maintaining the units that the soldered joints were better and when the time came to make repairs if possible I would tend to install a soldered joint as for example when replacing a damaged cable etc. At one customers the in house maintainance team had one of those super hydraulic crimping guns with selectable dies for differing sizes and if I had a lot of work on I would sometimes use this for its speed. Those crimped fittings would fail / crack at the point of entry to the terminal more frequently then the soldered units in a similar situation. Though this was usuallly on the ends of flexible leads etc. Another advantage with the soldered joint is that you can reuse the terminal if need be and use one that is larger than your cable size. having made hundreds if not thousands of soldered joints on battery leads and having watched battery makers engineers replace cells and leads over 15 years in the industry, the quality of the joint is in the making. Use shoes (lugs) and terminals that are made for soldering, not those with a small tell tale hole in as these are 'crimping' fittings, the tell tale lets you know the cable is fully inserted . a soldering terminal is just a socket and to fit it I would hold it verticaly, socket at the top , make sure its clean and well fluxed. Inset the cable which has had its insulation cut well back and its conductors also fluxed fully into the socket and held secure so that it wont move around. Apply the heat of a gas torch to the outside / bottom of the socket while holding the solder against the copper of the cable inside the socket. when the heat has moved sufficiently from the socket to the cable then the solder will start to melt. keep the heat on only for a short while now as the socket will begin to fill up. remove the heat when the socket is about half way full but carry on applying solder into the solder pool insde the socket untill the socket is full or untill the solder stops melting. This filling operation is the 'skilled' aspect of the job as keeping the heat on too long transfers too much heat to the cable which then makes the cable wick the solder up too much and makes the solder flow up and along the cable too much, though a little is required just beyond the confines of the socket. And too little heat means the socket and cable are not filled/wetted enough. practice here will show the way. Another method especialy with a cable that is small for the socket is to flux and partialy fill the verticaly mounted socket without the cable in and then to 'plunge' the fluxed cable into the molten solder pool and holding it very steady and keeping the heat on the socket until such time that the cable heats enough to draw the solder up at which time the heat is removed and the solder is 'topped' up to fill the now depleated socket. again practice will make perfect. Remember to slide any sheaths etc onto the cable before fitting the terminal.
Many people quote the aero industry is always using crimped joints and some state that on a particular Boing craft there is only two soldered joints out of several thousand ! my understanding of this having talked to the boys that make up the looms at the local BAE factory is that the crimps are accepably predictable and repeatable to a level of quality using rachet tongs etc where soldered joints are not as they depend too much on individual operator skills and environments. And the fact that Boing use any soldered joints at all must indicate that the see the soldered joint as a higher level/quality or why have they gone to the trouble when it would be so much easier just to crimp it !.
Make of all this what you will as on our boat ,which I share with my brother who was for many many years an electrician in the North sea and elsewhere, when it came to installing our DC distribution panel, he went and hired a crimping tool and crimped all our fittings!
Many people quote the aero industry is always using crimped joints and some state that on a particular Boing craft there is only two soldered joints out of several thousand ! my understanding of this having talked to the boys that make up the looms at the local BAE factory is that the crimps are accepably predictable and repeatable to a level of quality using rachet tongs etc where soldered joints are not as they depend too much on individual operator skills and environments. And the fact that Boing use any soldered joints at all must indicate that the see the soldered joint as a higher level/quality or why have they gone to the trouble when it would be so much easier just to crimp it !.
Make of all this what you will as on our boat ,which I share with my brother who was for many many years an electrician in the North sea and elsewhere, when it came to installing our DC distribution panel, he went and hired a crimping tool and crimped all our fittings!
JohnTH
New member
Wow ean p that was a lot of reading. I agree with you and your description of how to do it.
As a "scum" apprentice we had to sing "all things bright and beautiful" while cleaning whatever we had to solder. Flux was some sort of bakers fluid and I never ever found out what the "mole skin" was made of. Them were't days lad !
We tended to use a solder pot to tin the battery cables and straps (links) Also, remove whatever it iss to be soldered WELL away from the banks of batteries.
73s de
Johnth
As a "scum" apprentice we had to sing "all things bright and beautiful" while cleaning whatever we had to solder. Flux was some sort of bakers fluid and I never ever found out what the "mole skin" was made of. Them were't days lad !
We tended to use a solder pot to tin the battery cables and straps (links) Also, remove whatever it iss to be soldered WELL away from the banks of batteries.
73s de
Johnth
Chris_Robb
Well-known member
EAN P - interesting post, but it would be much easier and less daunting to read if you broke it down into paragraphs! PleaseeeeeeRogerMayne
Member
You will never find soldered battery cables on a production car, boat, truck etc. You will find crimped terminals with possibly a fuse or a fusible connection.
VicS
Well-known member
And having had one "production car"
in which a little bit of resistance in each of the crimped terminals added up through eight of them to enough to making starting on winter mornings with a battery past its initial youth difficult and having had to solder them all are the reasons I like soldered fittings. 
ccscott49
Active member
A bad crimp is a bad crimp, nothing to do with the theory of the job.
Same as a bad soldered joint is a bad soldered joint, but much more difficult to achive a good solder joint.
You can probaly achieve good soldering, lots cant, crimps are much more fool proof, even when done by an amatuer, if using pro kit.
I have crimps and pro crimping tools aboard for all my connections, be it, small or battery large. If you need them and you're in Barce;lona, let me know, I'll lend them to you, or anybody else from this forum. I also have coax crimping pliers.
Same as a bad soldered joint is a bad soldered joint, but much more difficult to achive a good solder joint.
You can probaly achieve good soldering, lots cant, crimps are much more fool proof, even when done by an amatuer, if using pro kit.
I have crimps and pro crimping tools aboard for all my connections, be it, small or battery large. If you need them and you're in Barce;lona, let me know, I'll lend them to you, or anybody else from this forum. I also have coax crimping pliers.
JohnTH
New member
The debate regarding soldering and crimping can, and I expect will, go on and on. Remember though that soldering is a craft skill that takes time and practice. Our modern world has little or no time for for craft skill. What a pity ! !
73s de
Johnth
73s de
Johnth
cliffordpope
New member
Alex_Blackwood
Well-known member
Before attemting to solder I would point out that the connections you have shown are crimp connnections. Solder connections would be much heavier and would be solid "cups".
May I suggest your best bet is to find an Auto Electrician in yellow pages and get a new crimped assembly made up.
I had a similar requirement a couple of years ago, albeit in Portsmouth, I bought the bits in the Port solent Chandlery went next door to the Volvo Penta shop and they crimped it up. For free!
Hope that helps.
May I suggest your best bet is to find an Auto Electrician in yellow pages and get a new crimped assembly made up.
I had a similar requirement a couple of years ago, albeit in Portsmouth, I bought the bits in the Port solent Chandlery went next door to the Volvo Penta shop and they crimped it up. For free!
Hope that helps.
Alex_Blackwood
Well-known member
elton
Well-known member
andythilo
New member
IMHO, you should both crimp and solder and then cover with self adhesive heat shrink. Also if connecting 2 batteries in series for 24v, you should have a fuse between the middle connection, i.e + Battery - fuse + Battery -
If that makes sense.
If that makes sense.
tinkicker0
New member
My tuppence worth.
Many vehicle manufacturers including Honda don't recommend soldered on connectors anymore, for the reasons others have given re making a stress riser in the wire.
I use crimp on type flag or bullet terminals at work with proper calibrated crimpers (and def not those orrible red, blue and yellow insulated Lucar spade types).
However for battery cables, I prefer to use tube type terminals and solder, covered with heat shrink to help keep moisture out of the joint.
I do not recommend the Boric Acid / Bakers solution type flux as in a boat it may promote corrosion in the joint.
Plumbers paste flux is the way to go as the lanolin in the paste acts as a barrier to keep out moisture and oxygen, much like petroleum jelly.
If the cable feels stiff more than a couple of mills out of the terminal, you have overdone the soldering.
Not a fan of crimping battery cables as unseen corrosion can set up a high resistance within the joint and I have had many head scratching moments with trucks with intermittent starting because of this over the years.
Both ways work fine and its a matter of preference as long as it is done right, with the correct equipment. Crimping it in the vice may work fine and you may get away with it, but it may fail when out at sea too.
Do it right and you only need to do it once.
Many vehicle manufacturers including Honda don't recommend soldered on connectors anymore, for the reasons others have given re making a stress riser in the wire.
I use crimp on type flag or bullet terminals at work with proper calibrated crimpers (and def not those orrible red, blue and yellow insulated Lucar spade types).
However for battery cables, I prefer to use tube type terminals and solder, covered with heat shrink to help keep moisture out of the joint.
I do not recommend the Boric Acid / Bakers solution type flux as in a boat it may promote corrosion in the joint.
Plumbers paste flux is the way to go as the lanolin in the paste acts as a barrier to keep out moisture and oxygen, much like petroleum jelly.
If the cable feels stiff more than a couple of mills out of the terminal, you have overdone the soldering.
Not a fan of crimping battery cables as unseen corrosion can set up a high resistance within the joint and I have had many head scratching moments with trucks with intermittent starting because of this over the years.
Both ways work fine and its a matter of preference as long as it is done right, with the correct equipment. Crimping it in the vice may work fine and you may get away with it, but it may fail when out at sea too.
Do it right and you only need to do it once.
Bilgediver
Well-known member
My tuppence worth.
However for battery cables, I prefer to use tube type terminals and solder, covered with heat shrink to help keep moisture out of the joint.
QUOTE]
So long as the joint is correctly soldered IE total penetration of the joint which the average tyro might find hard to achieve then not only does the heat shrink keep out the moisture,but if 3 or 4 layers are used of varying lengths from about L = 10*D L = 6*d with longest on the wire and tapering down to shortest outside, then this softens the joint and reduces the effect of the stress raising edge by spreading the bending over a longer length. This is especially important on the lugs attaced to the engine/gearbox and starter where there is sometimes a lot of movement especially with Yanmars when idling.
I must admit this is how I did all the battery cables and power cables on a Hunter Channel 32 built by a friend which was given a lifetime guarantee in about 2000 and we never found any problems with any of these joints including the negative and positive mounted on the engine when giving them their annual inspection. However I would not recommend anyone unfamiliar with soldering to attempt these joints without an afternoons practice as getting it right first time will be more a matter of luck than skill and the reason I was asked was because the friend had tried and been dissatisfied with the results of his handiwork.
It is important that the components are clean and correctly fluxed, that they are at the right temperature when the solder is applied and that no more solder is used than to fill the lug otherwise it wicks up the cable.
Always finish with at least a single layer of shrink sleeving over the lug and wire.
A solder iron is totally unsuitable for battery lead connections. You need to use a gas torch such as those supplied with disposable bottles around 500cc
size. The knack as was said earlier is to stop applying heat as the cup starts to fill so that the heat in the lug cup and wire is used to melt the remaining solder as it is applied. Too long an application of heat results in the whole assembly possibly being too hot as finished and the solder wicking up the wire.
The lug needs to be nipped in a vice by the drilled end and the wire held as still as possible to ensure a perfect soldered joint.
Once again....only if you are really satisfied with your practice attempts then proceed. Oh yes.....do not practice in the kitchen as hot solder does not improve the lino or wood floor
It is much easier to solder the wee yellow red and blue terminals however quite unnecessary if a ratchet crimping tool is used.
