Tinned Wire Alternative

[Inq720]

Preamble
I am going to be doing some wiring in a sailboat. From large gauge for the Inverter and Windlass down to tiny stuff needed for LED lighting. The boating industry has somehow gotten into its head that all wiring must be tinned, which seems strange, since apparently soldering a lug on a wire is no-no also. Apparently decades ago, some vendor did an article and everyone jumped on board till now its expected. Fantastic marketing! Turns out almost no boat manufacturers uses tinned wire and no standard actually specifies tinned wire. Anyhow it's expensive. I don't want to use it.

Question
Now I know from repairing and replacing trailer wire that it corrodes in wet environments. The trick is to seal all the stranded wire from the moisture. Heat shrink helps, but doesn't eliminate all paths. What I want to know... if I crimp the lugs on the wires, tape over the screw area of the lug and dunk them in plastic will this cause any problems?

I'd use scrap ABS plastic that I have from my 3D Printing and melt it down with Acetone. I can make it as thin or thick as I want it. Considering it would flow around the strands inside wire insulation would be great stopping water propagation down the wire. But it would also flow inside the lug. My first thought would be the crimping would make all the contact that is necessary and the plastic would simply be filling the air voids and not reduce the conductivity one bit. Yet... would eliminate moisture completely.

Any thoughts???
Any suggestions on how I could validate my theory?

 

[HRTKD]

Does your heat shrink have glue on the inside? If not, that's part of the problem.

My deployment is on an RV, not a boat. But I do have wiring outside in the elements, both on the roof and deployed on the ground.

 

[Inq720]

So you're saying some heat shrink has a glue inside and it seals up the end over all the loose strands??? The stuff I've always used seems to be just plastic and shrinks. I don't see any "plugging" on the end. I can still see the ends of the strands a millimeter or two in.

 

[HRTKD]

The heat shrink should overlap the lug crimp area and then extend over the wire insulation. I use closed end lugs. I thought that open ended lugs weren't considered marine rated.

 

[Inq720]

That's the missing piece... I need to find closed end lugs for all size gauges I need. Thanks.

 

[snoobler]

I typed this up yesterday and never posted...

I have no opinion on tin vs. no tin beyond soldering.

No way that an ABS/acetone slurry will meaningfully penetrate between strands in a properly (or marginally) crimped terminal.

Why not just seal it off with marine grade heat shrink? That stuff has an adhesive on it that bonds to the lugs and wire insulation sealing them.

As someone who has generated mountains of 3D printed ABS waste, has worked with ABS motorcycle body work, has used acetone with ABS for various things that worked from varying degrees of fantastic to crappy, and who has seen what happens during 3D printing when I don't protect ABS from humidity (in Arizona), I would choose marine grade shrink over ABS 1,000,000 to 1.

Regardless of how thin or thick is starts, once the acetone evaporates, it's way less flexible than the stranded wire. too much wire movement could open a gap.

 

[Mike Jordan]

How is soldering marine tined wire bad? I have not heard that, and I do it all of the time.
You tin a wire before you solder it normally. I have found the high strand marine tined wire sucks up solder like a fat kid that has missed a few meals. I love that stuff.

 

[Inq720]

It seems I failed to bookmark it before, but I had a reference that pointed to something in the AYBC standard. Trying to find it again, I ran into this one, but see it says you can solder after you crimp. My trouble is... I tried to solder (even with a 175 watt Weller gun) 6 AWG and couldn't do it. I guess the heat was escaping faster than I could put it in.

 

[Will Prowse]

Wow, this is interesting: https://www.practical-sailor.com/systems-propulsion/electrical/tinned-wire-myth-busted

My marine low voltage books always mention using tinned wire. I would still prefer tinned wire personally.

I suppose if you have a high quality marine grade heat shrink w/ adhesive, and an appropriate insulation for the environment, you can get by without using tinned copper.

And no, do not use the ABS. Use high quality marine grade heat shrink.

Why do you need to solder the wire? Industry standard for large lugs is a proper crimp. Solder is not a good idea for large lugs. And imo, unnecessary to "fill in the holes" around a crimp connection.

Crimping dry, clean copper to copper, then add marine grade heat shrink, and you should be good to go. I would still use tinned copper. Avoid solder for large conductors.

 

[Inq720]

Ye

Wow, this is interesting: https://www.practical-sailor.com/systems-propulsion/electrical/tinned-wire-myth-busted

Yeah... that's the article I was talking about in my Preamble. Surprises many people on the boating forum I haunt. They're "absolutely certain" tinning is required in ALL boating standards. Threw me for a loop too.

I've always used the open end crimps (not for boats... household projects). Didn't know better and didn't really take-note of the closed ones till re-reviewing your vid using your recommended capacity tester. BTW... your link is busted. Found this one on eBay. I was comparing and yours had the closed ones. Note: I tried to solder... worthless cold joint. But certainly need to invest in a good crimper... my biggest wrench could barely budge these. Resorted to a hammer to finally get the wires to stay in. Fortunately... just for testing.

 

[Will Prowse]

Ye

Yeah... that's the article I was talking about in my Preamble. Surprises many people on the boating forum I haunt. They're "absolutely certain" tinning is required in ALL boating standards. Threw me for a loop too.

I've always used the open end crimps (not for boats... household projects). Didn't know better and didn't really take-note of the closed ones till re-reviewing your vid using your recommended capacity tester. BTW... your link is busted. Found this one on eBay. I was comparing and yours had the closed ones. Note: I tried to solder... worthless cold joint. But certainly need to invest in a good crimper... my biggest wrench could barely budge these. Resorted to a hammer to finally get the wires to stay in. Fortunately... just for testing.

View attachment 30740

Yeah, you need a crimper. On your V+/- In lugs, they will fail every test around. And the solder does not look like it was heated to proper temperature on those lugs.

To have a true cold weld requires quite a force. Hammer can crimper IF you use a hammer + hammer crimper. Hammer alone, is a bad idea.

Buy a large high quality leverage or hydraulic crimper, and you will be set.

Oh ok, thanks for letting me know about my link. I will update that now.

 

[Zil]

"more-than-adequate service life in most cases."
"Without exposure to moisture "
"Be sure that the terminations on any cabling in your boat are hermetically sealed. Standard crimp connectors don’t do the job."
That are some maybe. Also, I'm retired from the Marine Industry. All the marine technicians I know use tinned wire rated at 105c, and they don't recommend other stuff.

 

[Will Prowse]

"more-than-adequate service life in most cases."
"Without exposure to moisture "
"Be sure that the terminations on any cabling in your boat are hermetically sealed. Standard crimp connectors don’t do the job."
That are some maybe. Also, I'm retired from the Marine Industry. All the marine technicians I know use tinned wire rated at 105c, and they don't recommend other stuff.

Agreed. And every marine electronics supplier I know only sells tinned copper. Besides some random hook-up 12 gauge wire.

 

[Dzl]

How is soldering marine tined wire bad?

My vague recollection is that the problem was not soldering, but rather relying on the solder for your electrical and/or mechanical connections.

Take the above with a grain of salt as its only something I vaguely recall reading in passing. But it may be a starting point to begin your research from (and then you can come back and tell me how wrong I was ?)

edit: whatever I read probably originally came from section 11.14 of the ABYC E-11:

11.14.5.7 Solder shall not be the sole means of mechanical connection in any circuit. If soldered, the connection shall be so located or supported as to minimize flexing of the conductor where the solder changes the flexible conductor into a solid conductor.

EXCEPTION: Battery lugs with a solder contact length of not less than 1.5 times the diameter of the conductor.

NOTE: When a stranded conductor is soldered, the soldered portion of the conductor becomes a solid strand conductor, and flexing can cause the conductor to break at the end of the solder joint unless adequate additional support is provided.

11.14.5.8 Solderless crimp on connectors shall be attached with the type of crimping tools designed for the connector used, and that will produce a connection meeting the requirements of E-11.14.5.3

There is much more guidance in that section, but the above is the part that was most relevant to solder.

 

[Zil]

Exception being very small guage wire used on circuit boards. Soldering any stranded wire causes the copper to harden. The vibration found in mobile uses can cause the wire to break. The only safe terminal is a properly crimped connection that results in "cold weld" of the lug and cable wires.