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Topic Review (Newest First)
08-03-2005 11:52 AM
Mustangsaly in some cases everyones way is best ! butt you got to pick the right application for the right connection. some times a crimp with alum wire dope (alumilux) sp in the crimp with the correct crimper and good heat shrink like A 3M brand, theres other good brands too is a Very Good corrosion free & weather tight connection, good heat shrink is available in many sizes at electrical wholesale supply houses. It is a very tough,flexible material, that has a heat activated adhesive-glue inside, and is UL approved to 600
volts, and can be direct buried in-ground. and the heat shrink from a electrical wholesale house is better quality than what you get from auto stores. this is an example how strong it is, i broke a handle on my post hole diggers, so i wood glued and clamped the broken area, then when dry i took a 12" piece of heat shrink and heat shrunk it tight to the handle, and almost 10yrs later and prob only 12 holes latter, it works like new, i also have a rake handle fixed the same way man kids are hard on old wood yard tools.

07-31-2005 09:14 PM
Henry Highrise Very interesting thread, there are many good answers and also a few bad ones. After reading them all I would have to say that 61bone has given the best answer out of the whole bunch. He makes a good mechanical connection, then a good solder job, and wraps it up nice. All the solder is really doing is holding the mechanical connection together and protecting it from coming apart. When done properly using his method all of the current is flowing throgh the good mechanical connection and the mechanical connection is secure and should last indefinately.
07-31-2005 07:32 PM
Kevin45 You have various soldering tools to use. You have the soldering guns as in the Weller type, you have soldering stations that you can very the voltage, you have soldering irons which you see a lot of people that make stained glass use, and you have a torch. Personally for inside of a vehicle and where you do not have real good access do not use a torch. You can get a larger soldering iron for larger wire. These heat up quite a bit hotter and have a larger heated surface for heat distribution. Normally we use this type at work for soldering lampholders to the ferrules and very rarely for wire. Most of the time soldering stations with variable voltage adjustment are used. Larger tips and more voltage for larger wires and smaller pencil tips and lower voltage for smaller wires and electrical components on circuit boards. Crimp connectors are fine and perfectly acceptable as long as the proper crimp tool is used. The cheap crimper's just crimp flat or mostly flat and can let the wire eventually pull out. A proper crimp tool will keep the wire strands in a tighter bundle while creating a good tight crimp. Also if some people think that a crimp connection is not any good for an automotive application, just figure that there is 12-14 volts going thru the connector. That same connector can carry 440 volts in an AC application. Here is a good soldering tutorial. CHECK IT
07-31-2005 06:45 PM
Bort Good luck!
Thanks willy
07-30-2005 09:33 PM
rapsag I think I will be happy with my butt and soldered joints, since:
1. I will not be pushing any more than 12 volts, and have circuit breakers for amps over 30 for my a/c fan and one for my compressor as well.
2. The car is not driven daily and not much in the heat of summer. It is more for show and occasional jaunts with the car club.

Butt (pun intended) I will check the joints often if and when I get the car up and running. If the high voltage lines are not hot at the joints, will not worry about them.
Having said all that, I am very impressed with the knowledge expressed in the thread and will certainly benefit. Thanks much. Wish me luck.
07-30-2005 08:05 PM
Fast Orange Gotta Add My 2 Cents-
I do a lot of wiring on trucks,trailers and equiptment for my employer.I have access to just about any type of crimper,butt splice and heatshrink you can think of.In my experience,the most reliable and toughest splice is a soldered splice insulated with a heatshrink tube that has an adhesive/sealer inside.My technique varies with the size of the wires ,but for larger wires I use a combination of Willy's and Grouch's methods.I start with a good twisted mechanical splice as Grouch described,then solder it ,as Willys instructed.I do use plumbers flux,for the same reasons as Willys.As previously mentioned,it is very important to clean up the joint after soldering to prevent corrosion.My prefered heat shrink is 3M type ITCSN,available in many sizes at electrical supply houses that carry 3M products.It is a very tough,flexible material(rubber/vynle?) that has a heat activated adhesive-glue inside,that is UL approved for up to 600 volts ,even directly buried underground.
07-30-2005 07:03 PM
61bone You're right that factory crimps can't be done with the average set of crimpers. A set of Paladin or MSD( yep the ignition folks)crimpers will set you back close to a Cnote and the jaws are about 30 bucks a set. If you properly calibrate them for a mil-spec crimp there goes another hundred. I set mine with a fish scale and I haven't had a crimp failure in years. If you inspect the ends on factory power feeds you will find they are soldered in addition to the crimp. I think you did just fine on your soldered butt joint and it will serve you well for quite some time, but when you do start having feed problems, look there first. The reason solder is used is not to transfer current from one wire to another but to hold the joint together. Solder and butt crimps don't provide this wire to wire contact and make a high resistance area in the wire that runs hot and will eventually fail.
Sounds to me like you aren't skiving enough wire on your 10ga. You need to skive about an inch and a half of wire on each side. Split each one in half for 3/4 " so you have a Y. Put the Ys together and twist the tails down the opposite wire. Use a couple pair of pliers to tighten the twist and lay down any ends. Use rosin core solder and a big enough heat source to heat the wire to solder temp very quickly so the insulation isn't effected. Use a self-sealing shrink tube to finish.
If you are t'ing off a 10ga skive about an inch and a half off the mainline but don't cut it off. Take a screwdriver and stick it through the skived area splitting the wire in half. Skive an inch and one quarter off your added wire. Stick it through the mainline split and divide it in half and wrap both ways down the mainline. Bend your added wire in the direction you want it to go, tighten, solder and finish
I'll shut up now
07-30-2005 05:15 PM
rapsag Professionally crimped wires are superior since the flexibility allows you to manipulate the wire after the closure. However, I have never been able to duplicate the professional product. Usually there is a crimp over the insulation as well as a 'bow tie' crimp on the wire which us amateurs cannot duplicate with our cheapo equipment. So, I would rather solder, protect and forget about separation. This has been a very good exchange. Thanks all again.
07-30-2005 10:06 AM
malc I gave up soldering when a friend in the industry pointed out to me,
no manufacturer of autos solders connections.
There again they have the big stuff to crimp securely.
I also found getting the wire up to temp to melt the solder made the insulation soft which after cooling was never the same.
Shrink tubing is neat, better than taping, which always peels.
07-30-2005 09:47 AM Another opinion on this subject; the only wires I solder on a car are the big ones - main hot lead, battery cable ends, etc. Everything else I prefer use a quality crimp connector 'cause over time it has proved to be a better connection. Although a soldered connection (regardless of what type of solder you use) is the best electrical conducting connection you can use, the solder solidifies the wire right at the connector edge and the flexibility of the multi-strand wire is lost. The solder soaked wire also seems to be much more brittle than a solid copper wire of the same size. I have had many of these small soldered joints break and cause an open circuit. Has happened just from vibration of being in service on a running car in spots I would have sworn were well protected. Crimp joints however have never failed that way for me. Once they are properly crimped, they last forever and conduct as well as a soldered joint. Crimp, give the connector a firm tug to be sure it is well attached and it will never give problems.
07-30-2005 02:36 AM
Originally Posted by Bort
???? Since when does any type of plumbers soldering stuff conduct electricity?
I mix my own flux. I've been professionally tech'ing guitars and electronics for 15+ years. I know what I'm talking about when it comes to soldering, wires, and making those types of connections. If you use plumbers solder, it's not going to conduct heat/electricity. The connection will not work. I'm the type of person that uses the right tools to do the job right. So I've never tried it but I'm quite possitive plumbers flux (or something "like" it) will not work with electrical solder.

Glad you got it done and it works, rapsag.
Plumbers are not aliens. If "plumbers soldering stuff" did not conduct electricity, how are the millions of old homes still sporting copper plumbing using that plumbing as a ground connection?

Years ago, copper water pipes were typically soldered using a 60/40 solder; 60% lead and 40% tin. Now whenever copper pipe is used, a lead-free solder is used. It is still metal, however, and still conducts electricity. Lead solders are used for electronics, sheet metal and radiators. Lead-free solders, such as 95% tin and 5% antimony or various alloys of tin and silver, are used where drinking water will come in contact with the solder.

The problem with electrical wiring and acid flux has nothing to do with the use of acid flux (either as a core of the solder or as "soldering paste") in plumbing. The problem is that it is corrosive. It will wick under the insulation of the wire and can come back out to haunt you. It's one of those things you might get by with in a pinch. Electrical work should always be done with rosin flux. Just like you should never use pliers on a bolt or nut.

Flux is not the conductor nor the connector in any splice. Its purpose is simply to clean the metal being joined and keep it clean until the solder adheres.

As for your years of soldering, I suggest you not bring such a thing up around here lightly. You may run into someone who has been successfully soldering for longer than you've been living. I was a "late bloomer" to electronics and was quite proud of building a little single board computer sometime in '81 or '82. Then I met some folks who were involved in some early vacuum tube encryption computers for the Air Force back before I got out of elementary school.

Attached for your amusement is a photo of my first computer kit. Every soldered connection, including every leg of each IC socket, I did with a 25W iron. That computer still works. No, I didn't use acid-core solder, but the fact the connections are still good indicates that I must have figured out how to solder. I've used the same basic soldering procedure for everything from computers, radios, cars, trucks, tractors, instruments to plumbing.

I'm sure there are some old electrical engineers on here who will get some giggles out of the attached photo and this discussion, but whether your ego or mine is bruised doesn't really matter. Making a bad connection of heavy wire in a car, which indicates it's a high current circuit, can lead to a fire. That heat-shrink tubing method is just plain wrong. Just melting a layer of solder to the wires is also wrong.
07-30-2005 01:21 AM As I said in my previous post I agree totally with Bort, for small wires by all means use electrical grade solder on small wires where an electrical iron works. However, on bigger wires there aren't many irons that have high enough heat flux to keep up with the big mass of copper that is conducting the heat away from the joint. Virtually impossible to get a well wetted joint that way. The only way I have found to heat big wire (10ga and up) is wit a butane torch. Once you have to resort to that type of direct flame heat, you need a flux that can stand up to the flame. Plumbers flux does, electrical flux (organic rosin) just burns and the joint is compromised. Plumbers solder is made of exactly the same metals as electrical solder so for sure it is plenty conductive of heat and electrical current. Even though the good old lead/tin solders are plenty conductive in their own right, the new lead free plumber solders are composed of tin, copper, and a small amount of silver - all very conducive metals!

As grouch says, if you properly fill the joint with solder all of the flux is washed out of the internals of the joint and can be removed from the surface by careful washing. Have been doing this type of big-wire joint for 40 years so I am pretty sure it works! I don't like putting the solder drop directly on an iron tip, especially flux core solder since the constant exposure of the iron tip to fresh flux eats it away rapidly. By properly fluxing the joint and indirectly heating it so the wire itself is hot enough to melt the solder you end up with a perfectly wetted joint that is stronger than the wire itself every time.
07-30-2005 01:15 AM
malc Use a butt bonnector, crimp first then solder, wrap with some insulating tape then slide the shrink wrap over the joint. Twisted soldered wire tends to have "points" that will cut through shrink wrap eventually.
If the soldering is successful the solder will "shine" if not it appears "matt".
If I were doing it in the car IŽd rather not use a butane torch.
Even with a good soldering iron, in car soldering is a pain.
If it is in an area such as under the dash, IŽd just crimp.
07-30-2005 12:42 AM
Bort Bead on iron is how it's done on guitars. He was saying he couldn't get them hot enough. This technique would have worked because of that. Got r done! good.
07-30-2005 12:34 AM
Originally Posted by
Also use paint on flux like plumber's flux.
???? Since when does any type of plumbers soldering stuff conduct electricity?
I mix my own flux. I've been professionally tech'ing guitars and electronics for 15+ years. I know what I'm talking about when it comes to soldering, wires, and making those types of connections. If you use plumbers solder, it's not going to conduct heat/electricity. The connection will not work. I'm the type of person that uses the right tools to do the job right. So I've never tried it but I'm quite possitive plumbers flux (or something "like" it) will not work with electrical solder.

Glad you got it done and it works, rapsag.
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