Electrical - joining two bare wires

[Hvymtl]

What is the best way to join to bare wires that carry a lot of current/heat?

My 2003 mercury 50 regulator shorted out and fried the wires at both ends melting / ruining the connectors, etc. I have a new regulator and want to splice back into the wires from the stator.

 

[888]

Re: Electrical - joining two bare wires

Nothing beats a hot solder joint. Then shrink some tubing over it to make waterproof. Don't forget to slide tubing on wire before u solder connection together

 

[Silvertip]

Re: Electrical - joining two bare wires

And add multiple layers of heat shrink.

 

[minuteman62-64]

Re: Electrical - joining two bare wires

Nothing beats a hot solder joint. Then shrink some tubing over it to make waterproof. Don't forget to slide tubing on wire before u solder connection together

OK, now I'm confused (again). I've read many posts on this board that say the crimped connections are superior to soldered connections for marine use. As an old time electronics hobbiest, who grew up on soldered connections, it took a long time to sway me towards the crimped connections. Now I have to go back?

 

[Jlawsen]

Re: Electrical - joining two bare wires

No, you don't solder in a marine environment because in order to get the solder to stick (read as clean the wire) you need to use flux core solder and that is a corrosive. You can never get it out and it will lead to problems down the road. The crimped, shrink connector is the best and like Silvertip say's, slide an additional heat shrink tube over the top of that. Anchor (Marinco) makes the marine grade crimp on shrink connectors but you can also get them at Home Depot however the selection is limited.

 

[TerryMSU]

Re: Electrical - joining two bare wires

Done properly, either can work. Done improperly, either will fail.

For solder you need to use no-clean flux. Most shade tree mechanics do not have access to no-clean flux. No-clean is a flux that has limited acidity and is thus it is acceptable to not remove the flux. BTW, flux can be removed with a solvent such as acetone. The problem is that it is very difficult to fully remove the flux, even with multiple trials.

To get a good crimp, you need a very tight crimp that is air-tight. Again, it is difficult to get an air tight crimp. The best crimpers are not cheap. One thing that may help is di-electric grease. This keeps the air and moisture out of the connection. I know that many of you will disagree with the di-electric grease, but I am in favor of using it.

In either case, heat shrink is a very good suplemental seal. The stuff that actually melts to the wire is the best option. Multiple layers may help as well.

TerryMSU

 

[Hvymtl]

Re: Electrical - joining two bare wires

I was worried that the heat would melt the solder connection (same for heat shrink). It melted all the plastic off the connectors and parts of the wire insulation.

 

[Bondo]

Re: Electrical - joining two bare wires

I was worried that the heat would melt the solder connection (same for heat shrink). It melted all the plastic off the connectors and parts of the wire insulation.

Ayuh,.... It melted, Because of the bad connection,....

A soldered connection will have less resistance, 'n won't heat up...

If it Does, there's a Problem, too much resistance...

Resistance equals Heat....

 

[glenn property of pam]

Re: Electrical - joining two bare wires

i realy dont understand the idea behind not using solder on wiring in a marine enviroment. the connections inside my fish finder are all soldered to the board. i like the idea of soldering a crimped connection as this can handle more current due to less resistance. once covered with heat shrink there should be no moisture in the joint or the heat shrink was applied wrong. (heat shrink should be heated from the middle out so no air gets trapped). so what am i missing?

 

[Jlawsen]

Re: Electrical - joining two bare wires

i realy dont understand the idea behind not using solder on wiring in a marine enviroment. the connections inside my fish finder are all soldered to the board. i like the idea of soldering a crimped connection as this can handle more current due to less resistance. once covered with heat shrink there should be no moisture in the joint or the heat shrink was applied wrong. (heat shrink should be heated from the middle out so no air gets trapped). so what am i missing?

You're not missing anything. Rosin core or Flux core solder is a corrosive but it allows the less skilled solderer to create a satisfactory join with less heat. If you use pure solder you still have to clean the surface of the wire to get a good bond and that requires some form of corrosive that is rarely cleaned off adequately when done in the normal marine shop environment. The boards on your electronics are washed several times and the soldering is done in a well controlled environment. If they are true marine products they are sealed from the environment.

Crimping and soldering has little benefit regarding resistance because the surface contact area is insignificantly different with regards to current handling ability. The only time I would solder is if I had a soldering iron and solder and didn't have the proper crimping tool or die.

I recommend using the Anchor marine grade shrink tubing and marine grade shrink connectors that have the glue inside. When shrunk with a proper heat gun the connectors will turn nearly clear and a small amount of glue will seep out from the ends. The extra heat shrink tubing over that acts as a strain releif and reduces the possiblity of another overheated wire from melting into it.

FYI I use a Klein J1005 crimper and I also have a full Klein die style crimper set but I don't use it much. This past weekend I pulled all the wiring out of my boat and rewired it from end to end. I did use the soldering iron a couple of times but only for making up antenna connectors for my radios. I also have a Bosch LED heat gun for shrinking and keeping my cigar lit.

When I was rebuilding motors, if a connector gave me even the slightest concern, I'd replace it and never had any problems. Most of those motors went on "Go Fast" boats and got the currappp beat out of them.

 

[SteveMcD]

Re: Electrical - joining two bare wires

I have only heard of two types of cored solder. Rosin core and acid core. Rosin IS a flux core for electrical purposes, and is NOT corrosive. I have no clue what acid core solder is for, but avoid it like the plague-it IS corrosive. The only time I have used acid as a flux is on sheet metal roof flashings and gutters. It removes the zinc galvanizing, and makes some interesting visible acrid smelling fumes in the process. I soldered all of my exterior connectors with rosin core 60/40, and three seasons of salt water, and one of fresh, no problem. It only oxidizes on the outside and wire brushing them will make them look pretty again. I have found lead free solder is more difficult. It seems to have a much narrower temperature range. I had a butt connector on my temp gauge go bad and found my engine wiring had three butt splices each. I am thanking my lucky stars it wasn't one on the ignition lead. I saw a boat on the jetty once. Not pretty. My solution was to replace the whole lead, all seven of them, and splice failure was no longer a concern. Less worries= more fun. Marine wire isn't that expensive considering...but I can't tell from here if that is an option.

 

[HopinImFloatin]

Re: Electrical - joining two bare wires

we use only sealed crimp connectors on all our wiring repairs in the shop(automotive) per GM recommendation. Get a good crimp with the proper crimper-dont break the plastic coating with a cheap/sharp edged crimper, compound crimpers work best. Heat shrink the connector until the glue comes out the end, and yes, heat from the center out. This connection will not fail. In addition to the actual crimp, the sealer bonds to the wire making it a good strong connection. We use these all the time and many wires these days are data related which will not tolerate accept a high resistance connection, especially data bus lines. You have to get the ones with the glue in them though, ive seen shrink ones without glue and they are not an acceptable alternative.

 

[jhebert]

Re: Electrical - joining two bare wires

Almost all electronic solder that is sold for general use has a rosin flux core. I have never seen a connection made with rosin-core solder corrode. I have some connections I soldered 50 years ago and they have not corroded yet. Everyone knows that acid flux solder is not used on electronics.

 

[spdracr39]

Re: Electrical - joining two bare wires

Why not just run a new wire instead of splicing? Then it will be fixed correctly and any other potential bad spots will be eliminated.

 

[Thalasso]

Re: Electrical - joining two bare wires

we use only sealed crimp connectors on all our wiring repairs in the shop(automotive) per GM recommendation. Get a good crimp with the proper crimper-dont break the plastic coating with a cheap/sharp edged crimper, compound crimpers work best. Heat shrink the connector until the glue comes out the end, and yes, heat from the center out. This connection will not fail. In addition to the actual crimp, the sealer bonds to the wire making it a good strong connection. We use these all the time and many wires these days are data related which will not tolerate accept a high resistance connection, especially data bus lines. You have to get the ones with the glue in them though, ive seen shrink ones without glue and they are not an acceptable alternative.

Good recommendation. What happens when you soldier the wire it becomes brittle from the heat and eventually will break off.

 

[bigheaded5]

Re: Electrical - joining two bare wires

I agree spdracr39 ! If and when ever you can, simply replace the wire and you'll avoid future problems. When you must splice, I prefer to use a solid CRIMP then coat it with NO-OX and shrink tube it tight, then another layer over it overlapping onto the insulation of the wire 1/8-1/4". Even when replacing the wire completely, youll be putting some kind of connector onto each end....and again I use a solid crimp item, NO-OX and shrink tube. I use a ratcheting crimping tool with specific settings for different gauge wires. having the correct materials and tools can make all the difference in the world.

I have soldered points onto control panels and other parts with standard solder and flux. I just make sure to use an electro cleaner to remove any flux and then the.... NO-OX and 2 layers of shrink tube. Its never failed me.

 

[TerryMSU]

Re: Electrical - joining two bare wires

Steve:
Just because you have not heard of something does not mean it does not exist. 20 years ago the electronics industry made a shift from rosin to no-clean flux. This is because rosin flux (RMA) flux is rosin mildly acidic. Given time it will damage wiring. The acid flux you mention is plumbing flux. You might get away with rosin, you will not get away with plumbing flux. BTW plumbing lead-free solder is not the same as electrical lead free. Frankly I would use leaded (sn60 or sn63) solder for my personal applications. If you insist on using rosin, I would recommend cleaning the connection after soldering using acetone or something similar. The big issue with rosin is that it will wick up inside the insulation and corode the strands of wire. This is especially bad when the strands are very fine. Even when you clean the connection, the rosin will still be up there inside the insulation causing damage.
TerryMSU

 

[TerryMSU]

Re: Electrical - joining two bare wires

I agree spdracr39 ! If and when ever you can, simply replace the wire and you'll avoid future problems. When you must splice, I prefer to use a solid CRIMP then coat it with NO-OX and shrink tube it tight, then another layer over it overlapping onto the insulation of the wire 1/8-1/4". Even when replacing the wire completely, youll be putting some kind of connector onto each end....and again I use a solid crimp item, NO-OX and shrink tube. I use a ratcheting crimping tool with specific settings for different gauge wires. having the correct materials and tools can make all the difference in the world.

I have soldered points onto control panels and other parts with standard solder and flux. I just make sure to use an electro cleaner to remove any flux and then the.... NO-OX and 2 layers of shrink tube. Its never failed me.

Good thoughts!
TerryMSU

 

[glenn property of pam]

Re: Electrical - joining two bare wires

after working in the electical field for years i find some of the arguement void or mute. anything done wrong will fail thats a given and solder is the harder and most time consuming way to joint the wires together but ive never seen a wire fail because the acid ate the wire. when working as a electrical tech on prototypes years ago it was spec'ed that all strained connections would be tinned before landing this was a pain but not option. quotes like heat makes copper wire brittle is slightly confusing as heat makes copper softer not harder. if the wires are twisted then soldered its not going to break unless the joint was made on a flexable section then either solder or crimp will fail at that point. a cold soldered joint will always be a point to fail and ive spent many hour working on control boards to find a joint that was made incorrectly.
i have made hundreds of underwater connections and i prefer crimps as they are fast and easy to use and i have the tools for the job and over the last 10 years i have never had a joint fail. no-ox is a great product but you have to be carefull that you dont get the product on the inside of the heat shrink or the glue will not bond to the insulation. until you get to special wire like the stuff used on aircraft then i can see no problem with crimp or solder. i thought the arguement of not using solder on a boat might have been something to do with salt water i never considered that it was with solder in general. vibration and twisting will break a wire over time as the cores were never designed to rub against each other so a wire going to a tilt and trim motor is always on borrowed time. dc joints will corrode over time which makes you wonder why you go to all the hassle to protect the joint to the wire then push a spade connection on a terminal thats exposed to the elements. thats where electrical grease or no-ox realy needs to be applied in the first place.

on a side note ive never seen a copper water/air con/propane pipe break at a joint because the acid from the soldering process ate the pipe maybe it just takes a long while.

 

[TerryMSU]

Re: Electrical - joining two bare wires

after working in the electical field for years i find some of the arguement void or mute. anything done wrong will fail thats a given and solder is the harder and most time consuming way to joint the wires together but ive never seen a wire fail because the acid ate the wire. when working as a electrical tech on prototypes years ago it was spec'ed that all strained connections would be tinned before landing this was a pain but not option. quotes like heat makes copper wire brittle is slightly confusing as heat makes copper softer not harder. if the wires are twisted then soldered its not going to break unless the joint was made on a flexable section then either solder or crimp will fail at that point. a cold soldered joint will always be a point to fail and ive spent many hour working on control boards to find a joint that was made incorrectly.
i have made hundreds of underwater connections and i prefer crimps as they are fast and easy to use and i have the tools for the job and over the last 10 years i have never had a joint fail. no-ox is a great product but you have to be carefull that you dont get the product on the inside of the heat shrink or the glue will not bond to the insulation. until you get to special wire like the stuff used on aircraft then i can see no problem with crimp or solder. i thought the arguement of not using solder on a boat might have been something to do with salt water i never considered that it was with solder in general. vibration and twisting will break a wire over time as the cores were never designed to rub against each other so a wire going to a tilt and trim motor is always on borrowed time. dc joints will corrode over time which makes you wonder why you go to all the hassle to protect the joint to the wire then push a spade connection on a terminal thats exposed to the elements. thats where electrical grease or no-ox realy needs to be applied in the first place.

on a side note ive never seen a copper water/air con/propane pipe break at a joint because the acid from the soldering process ate the pipe maybe it just takes a long while.

This is probably because the water flushes the acid off the connection. Effectively you have a very potent water clean flux. They used to use a less potent water clean flux for electronics, but no-clean finally took over. (Possibly because of polution concerns with the water clean stuff.)

TerryMSU