Sometimes Practical Sailor is Not So Practical..?
Just yesterday it was like Christmas. I went to the mailbox and both Professional Boat Builder and Practical Sailor were in there! Which do I read first....:eek:
Anyway, to my point. After reading PS cover to cover I flip the back cover and there in bold print I see the headline "Tinned Wire Myth Busted".
Now I know as well as anyone that the ABYC does not specify the use of tinned wire, heck I own a copy of ABYC E-11, but to totally diminish tinned wires value in a boat is just plain foolish, and short sided, on PS's part.
Sure, there were many truthful points made but the entire gist of the article was to portray un-tinned wire as suitable for marine use because it "has been used for years" and "provides more-than-adequate service life", which they then never defined. Of course they did end that sentence with "in most cases" to cover their butts....
"By using heat-shrink crimp terminals or adhesive-lined heat-shrink tubing on conventional crimp connectors, you can effectively seal the ends of all the wire on your boat."
While I totally agree with PS's points about using heat shrink crimp terminals, I disagree that using an adhesive lined heat shrink over a NON heat shrink "conventional" crimp connection is a suitable alternative to an actual heat shrink connector.
In my experience, it is VERY, VERY difficult to find a piece of adhesive lined heat shrink that will:
1) Fit over the existing nylon insulation on the non-heat shrink connector as this is a rather LARGE diameter and becomes more than a 3:1 shrink
2) Shrinks enough, from the diameter needed to fit over the insulated crimp connector, to make a proper seal around the wires OD and to properly seal the terminal end.
Can it be done? Sure, but you will WASTE many pieces of expensive adhesive lined heat shrink and crimp connectors while attempting to make your "hermetically sealed" connection, yet failing to make a solid watertight seal that is easily replicated.
It is much easier, repeatable and reliable to just use crimp terminals designed and sold with the heat shrink already built in to begin with.
"Without exposure to moisture, or salt air, the un-tinned wire will last as long as the tinned"
I can't even begin to agree with any part of this statement without them giving further clarification. This statement as written is totally and 100% misleading! Why? First off all wire jacketing is NOT the same. Many boat builders used cheaply jacketed wire, including but not limited to, "lamp cord".
The photo bellow was taken just last night! I went to re-wire my shower sump and found some older DIY wiring that did not meet my standards. Long story short, I am now doing a major portion of my re-wire, that I had planned for this winter, now.
This photo illustrates why the PS statement above is, to say the least, MISLEADING and dishonest. I cut this piece of wire from the CENTER of a 15 foot run. The wire had been encased inside a glassed in PVC conduit and was NOT in the bilge but rather half way up the top sides and out of direct contact with moisture. As you can clearly see from the photo this wire is severely oxidized and has turned black in the MIDDLE, or about 7 feet in from the end, of the wire! This is ONLY due to one thing, moisture, oxygen & humidity transmittance through the JACKET of the wire..! The flash and the stripping action of the wire actually made it look more like copper than it looks in real life.
"You'll need to strip back the wiring until you find clean, pink copper. Usually this requires stripping back no more than an inch or so if insulation."
LOOK AT THE PICTURE is all I can say...
You can't always believe what you read just because you read it in PS. Sometimes these authors don't fully investigate their own statements..
Cheap wire will oxidize and corrode THROUGH THE JACKET and MANY builders used cheap wire before the ABYC issued jacket ratings...! Even these UL/ABYC jacket ratings don't prevent and eliminate internal oxidation of the copper in all cases.
So yes even PS needs to do a BETTER job with their reporting and investigating...! Please read carefully!!!!
P.S. The factory wiring, not the DIY wiring, on my 29 year old Canadian Sailcraft is a bare copper duplex jacketed wire and is nice, clean and pink copper showing no oxidation.
The jacket on this FACTORY wiring, was, and is a top quality bare copper duplex wire that has very good insulation and jacket. What PS said CAN be true but they need to be very careful painting with a broad brush. A case in point would be factory wiring on my old Catalina 30 from the early 80's. This wire was totally oxidized throughout the entire boat! As I stated not all wire is created equal!
Oxidized Wire 7 Feet In From The Ends:
Middle of the Wire:
I understand the main points of your post and agree that PS is seldom practical as it routinely selects the most expensive product as the best although the writeup says the budget buy is fully functional (which to me is the definition of practical).
In this case tho' I think you might have missed the point. What PS reports is that the ABYC standard does not mandate tinned wire, and to quote 'the un-tinned wire has been used for years and provides more than adequate service life in most cases'
In THIS case they were, IMHO, being practical - it was not cost or functionally practical to rewire an entire boat simply because it was not wired with tinned wire. - Workman ship was good and the connections were anchor crimps with heat sealed ends.
This is in response to a guy asking if he should rip all the wire out of his boat even tho it was serviceable and of the right grade.
The jacket of your wire is perhaps not the only issue, based on it's location it was routinely submerged and therefore should have been a better grade and tinned, I also doubt the ends were sealed.
I've never had a problem using heat shrink as they suggest, but I've got a lot of training doing just that in the Navy as a electronics repairman (submarine Radioman) and a Metals Processing Specialist (welder, solder, braze etc) in the Air Force.
My 86 Hunter 31 did not use tinned wires and not one had a corrosion problem at 20 years old. I know because I checked the heck out of it - mind you not one was heat shrink sealed either - not even the bilge pump wiring.
Sealed, good jacketed, normal wires that don't see water intrusion are absolutely fine and good for 20 years - to me that is practical. At 20 years one expects to upgrade/replace things on a boat.
Again, I agree "GOOD JACKED WIRE" will be fine this however is NOT what PS stated they applied this "good jacked theory" to ALL bare copper wire which is why I have issue because as I stated all wire is not equal quality and they lead the reader to believe otherwise..
I would second that. I rewired my boat last year and had a chance to see what untinned copper wire looks like (granted, after 35 years on the boat). It was corroded and green everywhere along its length, virtually on every strand. That included wires that were completely isolated from the water, in dry compartments and all the way inside. It was a total mess.
While I don't have similarly aged tinned wire to compare, I did see tinned wire from 20 or so years back and it had none of these problems.
PS is full of BS on this issue.
I know that untinned wire has been used successfully for a long time but the differences are obvious to anyone who replaces fixtures on a regular basis. At least on masts.
Hmm... I think that it sort of depends on the application; many boat's harnesses are non-tinned (engine and 12V) and you don't see huge problems with fires. Yes; there are some here and there but when you look around marinas the vast majority are older hulls that likely don't meet current (or any) ABYC codes. That's not to say that many boats don't have hidden problems in their electrical systems. I'm just pointing out that the incedence of fires relative to the number of craft is pretty low.
Wire that is not under a high load (like a bilge pump or anchor windlass) usually will function normally until the strands are failing due to corrosion of the core of the strands. This generally does not happen; the surface oxidizes and it takes much longer for the strands to fail. The bigger issue is corrosion at the point of attachment to a crimp connector; and the oxidation increases the resistance at the contact point (resulting in heat). Again; the current being delivered makes all the difference in how much heat is produced. Some low voltage/amperage devices will cease to operate (like cabin lights); while others like battery cables and anchor windlasses would get hot/smoke or catch fire due to the high resistance and high current.
I'm not saying that oxidation of the wire strands is a good or in any way desireable; I'm just saying that surface oxidation is not necessarily a death sentence for otherwise good/serviceable 12V (low amperage) applications.
I think the practical queation depends on the individual. I have a 1977 Islander that has the origional wiring which none is tinned or shrik wrapped. All seems to work fine other than the occassional bulb corrosion.
I have had to replace some wires where previous owners had jerri-rigged added electrionic items. I chose to replace the wire rather than leave it in the state it was in using automotive stranded copper as it was compatable to what was in the boat. Has worked great with no issues.
The practical would be how long i planned on keeping the boat. The origional wire has lasted 31 years. I doubt i will keep her more than another year or so as i would like a larger more bluewater capable vesel.
If was was going to keep the boat for a more longer indefinate period of time i would probabily opt for the better qualiy. The optimum meaning you get what you pay for and the tinned, shrink wrapped is less likely to offer problems although the regular copper stranded will work. Even old light cords.
I haven't read this issue yet (probably will arrive with ON mag next week), but I am wary of blanket statements that ignore some fundamentals.
Is tinned wire critical in low-load applications in dry boats? No, not necessarily.
Will untinned wire and the usual crimping suffice in many cases? Probably, given that many wires on many "good old boats" are original.
Is replacing with Halekai's techniques those wires that fail or those wires that are "mission critical" (like bilge pumps, battery cables, nav lights) prudent and seamanlike?
Non-tinned wire will be dangerous on the boat in 10-15 years (and 15 year old boat is nowhere near it's end of life, presumably).
Marginally on topic :) So, I finally installed my golden-plated swan neck fitting (to lead wires from mast inside) - well, based on price anyway.
Now, there were a few reasons to do so - the old fitting doubled up the wire which probably was not good for its integrity, plus it was small and I couldn't add anything else. But also - there was a persistent and significant water leak - which I attributed to the fitting.
Well, today, as I took it apart it became obvious that fitting was absolutely dry. Water actually leaked in inside the wire. Yep, thats it - the triple wire for the combined masthead/deck light conducted water between its outer jacket and the inside wires all the way inside the boat. I guess I have another thing to thank Ches. rigging for (it would be nice to create an uspide down loop in the wire before leading it down to prevent this sort of thing). Anyway, this just goes to show that water can and does travel inside wiring - long distance and in large amounts.
(Incidentally, my fix for this was to strip outer jacket from the wire as it exits the mast, so water now should drain on deck - we'll see how well it works)
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