Rewiring and marine grade “tinned” wire

P

Peter

Well-Known Member
Joined
31 May 2001
Messages
345
Location
cumbria
Visit site
I’ve got to do a bit of rewiring on my yacht, existing about 20 years old, but in reasonable condition. Only reason to renew is to remove/tidy up all the “adds-on” made by previous owners over its life. My question, is it critical to use a proper marine grade “tinned” wire, or can I get away with using a standard “industry“ type multi strand wire. Any comments on wiring choice would be appreciated.

Thanks

Peter
 
I've got to re-wire my mast (nav lights) next winter because all the copper has gone black. Is tinned wire the same from any source? Is the "marine" tag just an excuse for the chandlers to put the price up?
 
Where the copper wire has tarnished, try a bit of Brown Sauce on it to clean it up ! If you don't believe me then take a 2 pence coin ( A dirty one ), and apply some of the brown sauce you get in sachets, and see how it removes the tarnish.
The other thing to do if you have untinned wire is to solder the ends that you are using to connect to, or with. The remainder of the wire might tarnish, but not the part that you have soldered. Cheers ! /forums/images/graemlins/grin.gif
 
as long as you go for 'tinned copper strand' , you should be OK , just find the cheapest source , although cable prices have taken a massive hike recently
 
For a dry boat, especially a moderate sized steel one such as yours, is not too critical inside the boat.

Personally I would specify such a boat as generally tinned for DC but not worry about that for cabling between terminations at the switchboard, or for large cables such as those between alternators and batteries or to invertor.

I would not worry about tinned for AC distribution nor for the shore cable.

In the end much equipment supplied and to be cabled to but supplied with cable tails such as small pumps, even if meant to be installed in the bilge (eg float switches and bilge pumps), will usually not be be supplied with tinned conductors, as will items such as the cables supplied with radios.

So is not something to panic over unless one has a wet boat. If there is any sign of corrosion after 15 years then one has a wet boat.

Would require to be tinned for DC cabling outside the boat to nav lights, but not necessary for coaxial cable to antennas in my view (whether it is tinned or not, once damp it is stuffed).

John
 
Use the \"right\" connections too!

Don't just use the standard "automotive" crimp connectors (you know, the red, blue or yellow ones), use the variety that have a glue-lined heat-shrink sleave. Crimp as normal, then heat with a hot air gun - the sleave shrinks and the glue oozes out thus making an air and water tight seal. Don't buy these (or the cable) from chandlers. Go for specialists like Index Marine or Merlin Equipment.

Re-wiring is a job you only want to do once, so pay a bit more and do it right! I'm in the middle of a re-wire myself...

Cheers,

Jerry
 
Re: Use the \"right\" connections too!

If you tin the ends of the wires yourself then dont use them in screw connectors as the solder creeps and you end up with loose connections.
 
Re: Use the \"right\" connections too!

Extract from ' The Marine Electrical and Electronics Bible
John C. Payne

Do not solder the cable ends. This practice is widespread because of a misconseption that soldering will make good connections and prevent cable corrosion. I have yet to discover any internal cable that failed due to corrosion, exept one in direct contact with salt water.
Solder can cause premeture fatigue becouse of conductor stiffness. In most case soldering is poorely done making hight resistance joint.

I would recomend that everone has a copy for reference
 
Re: Use the \"right\" connections too!

Well, if we all believed everything we read in books, or in the news papers, we would be in a right mess!

If the ends of the wire are properly tinned there is no problem in practice, only in theory. If on the other hand one sticks a big blob of solder on the end then one would expect a problem. /forums/images/graemlins/grin.gif
--------------------
hammer.thumb.gif
"Artificial intelligence is no match for natural stupidity"
sailroom <span style="color:red">The place to auction your previously loved boatie bits</span>
 
Re: Use the \"right\" connections too!

[ QUOTE ]
If you solder the ends of normal automotive cable the sleeving shrinks and melts onto the tinned end which seals the cable and is nearly as good as pre tinned.

[/ QUOTE ]Agreed. I use un-insulated crimp terminals then after crimping sweat them on with a little solder making sure to heat the insulation enough to melt it and seal the end then finish off by dipping the end in liquid vaseline and finally covering the joint with shrink sleeve for insulation/support of the joint. The trick is to heat the joint to melt the insulation <u>before</u> applying a <u>very</u> small amount of solder - just enough to fill the voids in the crimp. To avoid any possibility of fatigue of the joint I make sure the cable is well supported and fixed to prevent movement near the joint.
--------------------
hammer.thumb.gif
"Artificial intelligence is no match for natural stupidity"
sailroom <span style="color:red">The place to auction your previously loved boatie bits</span>
 
I'm glad you said this!

I'm doing all my 'dry' cabling in thinwall multicore - typically £0.24/m for 2mm as opposed to £1.13/m for tinned 2mm. All terminations either 'heatseal' pre insulated terminals for smaller sizes or tinned copper tube lugs and adhesive lined heat shrink for larger sizes (e.g. I've used 6mm for the bonding circuits). Tinned I use in small bits as you suggest for external cabling.

For UK buyers, I've found that ASAP Supplies 'marine' cable is EXACTLY the same stuff (same reels from same mfr) as 'automotive' cable from VWP - except the VWP is quite a bit cheaper (£36 from ASAP for 'marine', £24 from VWP for 'automotive' - 100m of 2mm)
 
What is important though, in my opinion, and what may or may not be accounting for part of the price difference you have found is that whether tinned or untinned the cable should be sheathed ie the conductors should be insulated as per usual and then they (that is the pair, if for DC) both be inside an outer enveloping insulation sheath.

Normal figure 8 type auto cabling, for example, is not in my view satisfactory for boats (even though considered so for cars). With sheathed cable properly supported one pretty much does away with the risk of chafe and shorting => fire or other problems.

John
 
You must log in or register to reply here.

Share this page

Top