Do you really need tinned wire and lugs?

[AHoy]

Yes!! Yes you do! I am doing lot of electrical upgrades to the boat. Previous cable was plain copper wire with copper lug wrapped in electrical tape.

New battery cables are tinned 2/0 wire with FTZ heavy duty tinned lugs and adhesive lined heat shrink.

[44'cruisingcat]

Considering the cost difference vs the hassle of rewiring in a few years, it amazes me that any would choose not to use tinned wire.

[BlackHeron]

Tinned wire is not proof against corrosion. It helps, but is not a magic bullet.

In fact, with the added costs of tinned wire it might be more cost effective to take that added money and upsize the wire two sizes (yes, tinned wire does cost that much more) and bump up that measely #14 wire to #10. It'll be more corrosion resistant (because it is oversized and has more meat on it so it won't overheat, the number one cause of wires going all black inside) and the connections will be much better as the surface area at the crimps will be MUCH larger.

Spend a little time and waterproof your connections with marine-grade shrink tube with mastic glue inside it and moisture can't get in there at all.

ABYC does not require tinned wire, it merely suggests it. Since the ABYC is simply a group of marine industry producers including the companies that make this expensive wire, I'm surprised they have not gotten up the courage to require it. Perhaps someday they will...

[DeepFrz]

Those are rather telling pictures.

[a64pilot]

Originally Posted by 44'cruisingcat

Considering the cost difference vs the hassle of rewiring in a few years, it amazes me that any would choose not to use tinned wire.

I would have agreed with that statement as all aircraft wire is tinned and that’s my background.
However the original wiring in my 1987 Boat is not tinned, and yet all of it I have inspected is in excellent shape, even the battery wires.
I have to think that good practices account for that as I can’t come up with any other reason.
However vinyl covered wire to me seems cheap, and all the good tinned Marine wire is apparently insulated with it.

However every piece of wire that I have added, and there has been a great deal of it, is tinned, cause well, why not?

[skipmac]

Originally Posted by a64pilot

I would have agreed with that statement as all aircraft wire is tinned and that’s my background.
However the original wiring in my 1987 Boat is not tinned, and yet all of it I have inspected is in excellent shape, even the battery wires.
I have to think that good practices account for that as I can’t come up with any other reason.
However vinyl covered wire to me seems cheap, and all the good tinned Marine wire is apparently insulated with it.

However every piece of wire that I have added, and there has been a great deal of it, is tinned, cause well, why not?

Exactly the same experience. My boat is a 1984 and with one or two minor exceptions (bilge pump and negative cable to the windlass), all original, untinned wire is in excellent condition. But I also used tinned wire for everything new or when I went to a larger size because, well why not?

[HopCar]

Prior to the late seventies I don't recall seeing tinned wire on boats. We got by fine with plain copper. To me the important thing in marine wire is to have lots of fine strands instead of fewer large strands. The wire is more flexible with fine strands and less likely to break.

That said I do use tinned wire but also make sure it is fine strands like Ancor uses.

[Wotname]

Originally Posted by a64pilot

I would have agreed with that statement as all aircraft wire is tinned and that’s my background.
However the original wiring in my 1987 Boat is not tinned, and yet all of it I have inspected is in excellent shape, even the battery wires.
I have to think that good practices account for that as I can’t come up with any other reason.
However vinyl covered wire to me seems cheap, and all the good tinned Marine wire is apparently insulated with it.

However every piece of wire that I have added, and there has been a great deal of it, is tinned, cause well, why not?

This probably the biggest difference between aircraft wire and boat wire.
There are quite a few different insulations used in aircraft wiring and they are all (but one) far better than the best PVC marine wire. There are also various metals used for tinning aircraft wire and they have specific purposes.

Finally, as a rule of thumb, aircraft systems use the smallest gauge wire that suits the purpose and voltage loss is not normally a consideration - but weight is

[thinwater]

A few things.

First, how old was the boat?

Second, there is something fishy in the photo. Not only is the wire damaged, but the copper lug is nearly gone. The answer, obviously, is that there was a battery or charging problem causing massive off-gassing and sulfuric acid fumes. Tin plating would have delayed the damage for a few months, bot in the end, the result would have been the same.

Third, finely stranded wire ONLY helps in the presence of significant vibration, such as near the engine, where it is required. Everywhere else it is actually more vulnerable to corrosion that standard stranding. It is not "better" for all uses, it is better for some and worse for others.

I've had several boats with copper wire. They used tinned wire for a few wet areas. Damage? Not a bit in 20 years or more. Just for laughs, take a look at the wire inside the typical systems on a boat (heater, AC, inverter) and tell me if they look waterproof to you. You need to keep the cabin dry.

[Rhumbline]

You definitely need to use tinned wire. Just look at any non tinned wire that's been on a boat a year or two. My non-tinned HV wire used as an antenna feed line was oxidized throughout after a year. Bought at HRO as 'marine grade'. Unusable after one season. Supposedly marine grade. Made in China. Total junk.
Don't even think of using non-tinned wire for a high-current load like a windlass. Or for anything on a boat. There's a reason for tinning wire in a marine environment. Ordinary wire might work for a time but it will become problematic and possibly dangerous after a time.

[Ostinato]

I had a Datamarine engineer tell me once that studies showed as long as you tinned the ends of wire, tinned wire had no advantage over non-tinned copper. He said they didn’t understand why. That said I still use tinned if I can get it.

[Zil]

Considering the amount of wire I could possibly use for my self, the difference in cost is not the issue.

[mikedefieslife]

It looks more to me that the copper lug corroded which is what then led to corrosion of a part of the wire below the heat shrink (edit, just read that it wasn't even heat shrink but electrical tape - well there you go). Had a non copper lug and adhesive shrink wrap been used it would probably be fine.

IIRC from another thread it was stated that some manufactures don't even used tinned wire when they initially install the boats wiring loom.

I'd say it's not essential but very nice to have.

[BlackHeron]

Originally Posted by AHoy

New battery cables are tinned 2/0 wire with FTZ heavy duty tinned lugs and adhesive lined heat shrink.

That crimp looks awful to me. What did you use to crimp it? A hammer and a cold chisel? A decent hydraulic crimper is <$40 on Amazon. Why destroy good $5+ each marine-grade lugs with cave-man crimping techniques when the proper tool is not much more than the crimps cost?

http://a.co/iTZ3gOz

Also, you need to use more heat-shrink than that. It should go up almost all the way up to the flat area on the lug to get a good seal and go back at least 2" back on the wire insulation for proper strain-relief. At least you used marine-grade shrink tube with the mastic glue inside. It's hard to tell, but it looks like you left a lot of room between the insulation and the lug. It should be no more than 2-3mm after the crimp. Be sure the wire is fully inserted into the lug all the way to the front and don't allow it to get pushed out in the crimping process. A proper crimper helps with this greatly.

A proper crimp with thousands of pounds of pressure (8-ton is about right) will cause the strands in the wire to flow and deform as the crimp flows and deforms over it so that it basically one solid piece of metal. Adding in a little anti-ox grease helps the deformation and the flow go a little better as it lubricates the process and actually makes the crimp tighter (the same reason you lubricate a seatpost on a bicycle with grease when you tighten it which is counter-intuitive to non-mechanics. It will not slip with less bolt pressure than one that is not greased with more pressure on the bolt. The anti-ox grease also protects from moisture if any should ever work its way in there or was trapped in the initial process. There is always a little moisture in the air, so it is impossible to not have a little moisture in there trapped during installation.

[Olddan1943]

West Marine has been selling non-tinned copper wire for many many years. I doubt if the floor personnel are away of the ABYC requirement for tinned wire. They just keep selling the non-tinned wire.
I will agrees, provided the environment is reasonable on the boat, the wire will outlive me, at least.
I have been using non-waterproof crimp fitting for years, but like the non-tinned wire, the environment is not in a humid area.