Hi All,Just yesterday it was like Christmas. I went to the mailbox and both Professional Boat Builder and Practical Sailor were in there! Were do I read first....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 never defined, of course they did end that sentence with "in most cases" to cover their butts.... Point #1Quote PS:"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, in the process of attempting a seal, and failing to make a solid seal. It is much easier, repeatable and reliable to just use crimp terminals designed and sold with the heat shrink built in to begin with.Point #2Quote PS:"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 PROVES the PS statement above is MISLEADING to say the least. 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 that was NOT in the bilge but rather half way up the top sides and out of direct contact with any water or bilge 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..!Here's another misleading PS quote: "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, like the Don Casey comments yesterday, don't fully investigate their own statements..Cheaply jacketd 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. I don't have a good answer of which jackets or insulation materials or ratings WILL 100% prevent oxidation through the jacket but I do know that many will as I have seen this numerous times on numerous re-wires. Tinned wire is a safe bet unless you know for a fact the jacket or insulation will 100% prevent internal oxidation through the jacket of the wire.So yes even PS needs to do a BETTER more thorough job with their reporting and investigating...!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!
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