Why not to use solid core T+E!

Daydream believer said:
...blackening as one oft sees on stranded wire...
Click to expand...

Daydream believer said:
One reads about having tinned wires. But in all the years I have had boats i have never purposely used any - unless it has been supplied with an instrument.
Click to expand...

To prevent the former follow advice you have read in the latter. Tinned cable on boats is most useful in wires that terminate outside. Elsewhere, less so.
 
Black wire is not such a problem as the OP's ... Black Wire just leads to loss of power .... but OP's can lead to fire or death ..

Black wire occurs in many realms - not only boats .... particularly prevalent with -ve wires on many DC circuits ...
 
AngusMcDoon said:
To prevent the former follow advice you have read in the latter. Tinned cable on boats is most useful in wires that terminate outside. Elsewhere, less so.
Click to expand...

It reduces Black Wire - but easily negated by use of terminals that break the surface tinning ... seen it .. got the T shirt ... and is why I no longer waste money on it - for PERSONAL use ... cheaper to just replace the cable 10yrs or more later !!
 
AngusMcDoon said:
Solid core cable is prone to fatigue failure where there is any movement or vibration. It's not the run of cable that's at risk, it's where the cable goes into a terminal that breakage happens.
Click to expand...
You say that, but some connectors apply pressure to the wire- ie choc box types & that makes a break point a fraction from the screw. Some put bootlace ends on the wire ( I do) to support it so that just pushes the flexing a bit further away from the fitting. Some use crimping , but that leaves a stiff bit of cored wire out of the crimp. Some solder the end which leaes a stiff length of wire. There are plusses & negatives with all types
Apart from that though, I am not entirely convinced that a properly fitted T & E would be any worse in a 13 amp socket as part of a ring main on a boat- which is what I suggested, Same for the fitting at the Nav light on the bow or stern. Is there any vibration there? If there is, one should start looking at the reasons why, as other connections within electrical components might be at risk.
 
Last edited:
AntarcticPilot said:
You NEVER, EVER add water to concentrated sulphuric acid! The dilution of sulfuric acid is STRONGLY exothermic, and the first drops of water boil, giving a VERY nasty steam explosion that throws concentrated acid all over. To dilute sulfuric acid, you ALWAYS add acid to water, so that the heat can be absorbed in a large exces of water. Even so, you do it slowly to allow the heat to dissipate.

Almost a knee-jerk reaction, it was drummed into us so well in school and university laboratories!
Click to expand...
What do you do for a spill?
 
westernman said:
What do you do for a spill?
Click to expand...
When acid is spilled on skin it spreads out in a thin film, like paint. Epoxy in a cup will exotherm, but it will not exotherm once spread out.

Same thing here. If you spill concentrated acid on your skin you strip the clothing off and them rapidly flood the skin with lots of water, removing and cooling the acid. The exotherm is spread out over a large area and is not as important as removing the acid quickly. It is getting water from under the skin anyway.

Throwing water on large puddles on the ground is a different matter.The choices are to contain with inert materials, pump it up if proper equipment is available, or neutralize, typically with lime or lime slurry. Multiple factors much be considered. I've been involved in two spill clean-ups (drum and 8000 gallons) and both times we used lime slurry kept on hand, in part, for that purpose. Yup, there were considerable fumes, but the areas were remote.
 
As with many things on a boat there is what you should use to make it as reliable as possible and there is much cheaper which often is also perfectly capable of doing the same job but maybe more vunerable.
A bigger problem than the type of wire used is the skill level of the person doing the wiring.
My 40 yr old boat is essentially a home build and does have a fair amount of house type wiring. It was wired so engine and domestic shared the same batteries. Was ok for a simple boat.
Over the 30 years ive owned it ive added a lot of electrical and needed to seperate engine from domestic. It was easier to just rewire and i reused a lot of the wire.
Ive never has electrical issues other than exterior where water has got in. I would always choose flexible over solid core as soldered ends must be better.
Im not a total cheapskate as my vhf coax rrp is over £10/m , but wow, it makes a huge difference.
 
AntarcticPilot said:
You NEVER, EVER add water to concentrated sulphuric acid! The dilution of sulfuric acid is STRONGLY exothermic, and the first drops of water boil, giving a VERY nasty steam explosion that throws concentrated acid all over. To dilute sulfuric acid, you ALWAYS add acid to water, so that the heat can be absorbed in a large exces of water. Even so, you do it slowly to allow the heat to dissipate.

Almost a knee-jerk reaction, it was drummed into us so well in school and university laboratories!
Click to expand...

Lab and on dock are two different worlds ....

The safety reqts of Acid loading are to have water supply to literally blast away the spill .. we are not talking about a piddling tap water stream - we are talking fire hose volumes ...
The action is to pass as quickly through the 75% concentration as fast as possible and to maximum dilution ...

Sorry - but I've been in this game too long ... and I've actually been victim of a joint failure in a pipeline .... where 95% Sulphuric Acid sprayed onto my legs and torso ... I immediately jumped to the emergency shower on deck where the 'boiler suit' literally just fell away in shreds ...

the action is to totally dowse in high volume water ... or be maimed for life or die.
 
rogerthebodger said:
Baking soda also called bicarbonate of soda

I ue it for neutralize hydrochloric acid after derusting any steel and before painting
Click to expand...

Great ... so please explain how to neutralize a spill of say 10 tons rapidly increasing at rate of 500 tins per hour during time to shut down pumps ??

Guys - you have to note that ships transfer at 1000's of tons per hour ... by time a spill is noted - and pumps stopped / valves closed - you can be talking more volume than your entire yacht !!
 
NormanS said:
Classic thread drift. Copper wire to sulphuric acid. 😄
Click to expand...
But you know what, there can be a lot covered by drift. Mostly, I enjoy it.

The original topic, while interesting, has been long covered by practice, experience, and standards.

But going back to solid wire! Solid wire is stiffer and much harder to pull, which may have contributed to the the problem (depending on what actually happened). My guess is that the stranded wire we use on boats was an outgrowth of the stranded wire we pull through conduit, which is a much, much larger market. And THHN (NEC) stranded wire is approved for boats and ships, though tinned is preferred. I'm not sure of the IEC equivalent designation.
 
Daydream believer said:
You say that, but some connectors apply pressure to the wire- ie choc box types & that makes a break point a fraction from the screw. Some put bootlace ends on the wire ( I do) to support it so that just pushes the flexing a bit further away from the fitting. Some use crimping , but that leaves a stiff bit of cored wire out of the crimp. Some solder the end which leaes a stiff length of wire. There are plusses & negatives with all types
Apart from that though, I am not entirely convinced that a properly fitted T & E would be any worse in a 13 amp socket as part of a ring main on a boat- which is what I suggested, Same for the fitting at the Nav light on the bow or stern. Is there any vibration there? If there is, one should start looking at the reasons why, as other connections within electrical components might be at risk.
Click to expand...

Yes, I along with the rest of engineering do say that. It's a result of a century of testing, experience and standardisation. That's how engineering works. Engineering best practice is not to use solid core wire in applications where there is movement or vibration - hence you won't find it in a car, ship, aircraft - or professionally built boat. Crimping or ferrules on stranded wire have been found to be the most reliable way to make electrical connections in these applications. However, your boat - you do what you want or think best - but don't expect any of your connections not to vibrate when you stick the donk on.
 
Last edited:
Daydream believer said:
Agreed on that one
But just for debate
What standard says that T&E cannot be used on a private yacht used for non commercial use.
Click to expand...
In the US, USCG regulations prohibit solid wire on both commercial and small private boats. This includes both new construction and maintenance work. This goes back 50 years or more. If a fire resulted you would face an uphill fight, since this is among the most blatant violations and is evidence of poor (non-seaworthy) maintenance. It just is not done.

Obviously, this depends on the insurance company, the details of the policy, and the adjuster's attitude. Most policies contain exclusions for boats that are not maintained in a seaworthy condition. For example, if a an old hose fails and the boat sinks at the dock, that's on you.

UK and EU, I don't know.
 
Daydream believer said:
What standard says that T&E cannot be used on a private yacht used for non commercial use.
Click to expand...

ISO 13297:2020​

Small craft​

Electrical systems​

Alternating and direct current installations​


The legislation doesn't say that you can't use it. It's part of RCD so legislation says that you cannot put a new boat on the market that doesn't meet this standard, which precludes it. Once the boat is yours you can butcher it how you like.

Anyway, all of engineering says that it's not the best idea to use solid core cable on a boat, but you'd probably get away with it. You do and believe whatever you want. That's enough from me.
 
Last edited:
You must log in or register to reply here.

Share this page

Top