Soldering Connections

davem222

davem222
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Hey guys,
I've seen a lot of guys say that to do electrical connections right you should solder the wire to the connector. I've been trying to find a video or how to with pics on how to do that but so far, no luck. Is it just a matter of crimping it and then applying solder to really get it on there? Thanks.

Dave
 
It's been a long time, but if I recall correctly you hold the soldering iron tip on the connector until it is quite hot, then apply the solder to the wires where they go into the connector and it will melt into/onto the connector. It sucks up into the wire strands. But it's been a long time and I never did a whole lot of it...I'm sure there are tutorials on the web for soldering.

Looked it up on BING. Here is just one under "Soldering techniques":

http://www.bing.com/videos/search?q...AF99A65B4C5143B5D6D7AF99A65B4C5143B5D&first=0

Good luck!
 
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Either would work, but I would be disappointed with the second one not being able to do 10 Gauge wires for the price. As far as soldering goes, You don't want to get a 15 dollar iron. It takes way too long to get enough heat in the connections, and the insulation will start to melt before the solder will. You need about 500-600 degree iron to make swift work. Also, a small tin of flux will work wonders. Go to Radio Shack and get fine solder so it is easier to handle. To do connectors, get some flux on the crimping end of the connector, and the wire. Crimp it lightly, just enough to hold it in place, then heat the joint with the iron, at the ends of the wire, and begin to tap it with the solder. Don't touch the solder to the iron, it will flow onto the iron instead of into the joint. Heat from the opposite side that you are loading the joint from. Once it melts and flows, feed it into the joint till you see the solder on the back side of the connection. It cools to solid in about 3 seconds. Give it another snug with the crimper.
CAUTION! If you are going to solder joints, don't use a ratchering type crimper!! It is possible to load the joint with enough solder that the crimper will not crush it down to the preset dimension.
 
+1 for very hot iron
+1 for thin solder (DO not use the thick plumbing stuff from Home Despot)
+1 for flux

And - it helps to clean the tip of the iron when it's dirty and has a lot of carbon on it. Often a wet rag works (when the iron is hot) or use a file or sandpaper to lightly buff it when it's cool. Then, heat the iron and "tin" the tip of the iron with a bit of solder once it's hot. You can also dip the tip of the hot iron into some flux to clean it.

As the previous guy said, use flux on the joint, and put the solder on the joint, not on the iron. The bigger the joint (bigger the wires) the hotter your iron needs to be.

I've got a medium sized one and it's fine for most motorcycle connections.
 
I was never able to install crimps very well until I got a good crimping tool. I found this very one years ago at work and it works great .....

http://www.ebay.com/itm/Vtg-Thomas-...m-/320895517661?pt=Pliers&hash=item4ab6dd03dd

I solder them as well after crimping then cover with shrink rap. Those hard plastic insulator tubes that come on many crimps are junk. I don't even attempt to use them and cut them off before crimping.

And in case you've never heard of them, Thomas and Betts invented the crimp over 70 years ago. Their crimping tools are some of the best and can be had quite cheaply on eBay.
 
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Here is my two cents worth on soldering connectors.

Make sure everything is clean (no grease, corrosion etc.) solder will not stick for want of a better word to a dirty surface.

For flux use resin cored solder do not use a liquid flux as these need to be washed off the item soldered to prevent corrosion. I do not advise using liquid flux for electrical connections. Paste flux is messy.

The resin and paste flux if not cleaned off the contact area of the connector when it has cooled will act as an insulator.

Do not solder wires then crimp them or put them under any form of compression termination. They might look neat and tidy but they will fail.
Soldering makes the copper lose its natural resilience enabling screws and crimps to work loose.

A properly crimped connector does not need to be soldered but if you feel you need to: crimp first then solder.

Don't let the solder travel past the cable insulation clamp portion of the terminal. The solder travels by capillary action up the strands of the conductor and the cable becomes rigid for a short section. At the point of transition from rigid back to flexible (or semi flexible) the cable will break over time with vibration.

A well soldered joint looks shiny, a dull joint is poor and is called dry and is either already a dud or will fail over time. Dry joints can be caused by not enough heat, dirty surfaces and most often on motorcycles movement before the solder has cooled.

I have just read this and it reads like a lecture, sorry but there was a fair bit to impart.
 
No soldering needed or recommeded if you ae going to use crimp connectors. In my airline maintenance days they taught that soldering is a bad thing. Causes stress at the end of the solder joint with possible failure. A good quality term end of the right size with the proper crimper does the job as good as ever needed. Get epoxy terms if you can. When you heat to shrink a built in epoxy oozes out with the shrink and makes it as permanent as it gets. Get a real crimper to and quality crimps. I have Panduit stuff. made right, lasts forever. The only place I use solder is for making up battery cables and i solder after the end is crimped on. Takes a heavy duty iron to get it hot enough when soldering big cables.
 
i get connectors from the mom/pop hardware store. they are tuff as shit, not like the harbor freight 3000 piece pack for 5 bucks. butt joints i dont use connectors, just mesh the wires together and solder, and then heat shrink. i use the resign core wire. tin your tip for good heat transfer. one thing that will help is the helping hands. basically alligator clips connected to a magnet. also if your connectors have the little plastic blue, or red, or yellow things on them, hit them with a heat gun or something to get them out of there. no reason for them.

before my first time soldering. i went and got a huge cheap pack of connectors and cheap spool of wire and practiced a bunch. you dont want your first soldering to be at your battery, or one of those thin wires coming off the pamco.
 
I usually put a small amount of solder directly on the soldering iron tip, it should be shiny when hot if this is done right. The small amount of wet solder helps with rapid heat transfer. I have found that a 20 watt Radio Shack iron will do 95% of all bike stuff (and car too, for that matter). It just has to be fully hot before touching the joint.

Ambient temp has a lot to do with it as well. If it's 30 degrees in the shop, the wire etc will be cold. In that case, I use a larger 40 watt iron.

I pull those plastic 'barrels' off the connector, slide a piece of shrink wrap WAY back up the wire, put the connector on and crimp it. On 14 gauge and up, it's possible to pinch the connector at the 'split' and crimp the full length of the metal onto the wire, then pinch the other side on top of that. I'll need to post a pic to show what I'm talking about. Then point the connector up, apply the iron to the barrel of the connector, then put the solder at the point where the wire comes out on the terminal side and wait for it to melt. When it melts, take the iron off immediately. OBTW: if the solder 'sticks' to the tip of the iron, it's either dirty or not hot enough.

I have had little to no luck with the soldering 'guns', not really sure why. I think the
'loop' allows too much heat to be radiated away. I just quit using them.
 
Thomas and Betts is good for connectors, tools, and tywraps.
As far as soldering weakening the copper wire, it is already annealed, so I don't know how that can happen. I have seen reference to strain relief sheathing being used as the solder joint acts as a "stop point" for flexibility in the wire, so the movement stops at the end of the solder joint, and that's where the wire will fail. think of putting a coat hanger in a vice and working it back and forth. It breaks at the vice jaw, as the immobility of the wire in the jaws forces the energy of the movement to be concentrated into bending the wire at essentially a fulcrum point. The strain relief sheath, (this can be done with a couple of pieces of heat shrink) absorbs the bending force into the sheath, so the full bending moment cannot reach the fulcrum point.
I am also one that ditches the sheath and uses heat shrink, unless it is a service joint, in which case a Molex connector from Radio Shack is my preferred part.
Heavier paste flux is indeed corrosive, but there are UL listed non-corrosive flux pastes available. I have used them for years on aircraft.
Also, and very important with older bikes: If the wire looks like anything less than a new penny (sorry, non-North Americans, I don't know if you have copper-clad coins) the wire is already corroding, and should be replaced, as you will not stop it, and crimp or solder, it will eventually fail.

$0.02 in the bucket, I'm done.
 
Wow guys, thank you thank you, SO much good info. Lol, about to make my first custom wiring harness and now I have lots of food for thought. Thanks!

Dave
 
A properly crimped connector does not need to be soldered but if you feel you need to: crimp first then solder.

Don't let the solder travel past the cable insulation clamp portion of the terminal. The solder travels by capillary action up the strands of the conductor and the cable becomes rigid for a short section. At the point of transition from rigid back to flexible (or semi flexible) the cable will break over time with vibration.

No soldering needed or recommeded if you ae going to use crimp connectors. In my airline maintenance days they taught that soldering is a bad thing. Causes stress at the end of the solder joint with possible failure. A good quality term end of the right size with the proper crimper does the job as good as ever needed.


:thumbsup: :thumbsup: :thumbsup:

I love soldiering, have since I was a very weird 5 year old kid, but these statements are the truth. Don't over do it, you might think you're making a better connection, but you're setting your bike up to fail when you're no where near your garage.

- Adam
 
The problem with solder is it makes the stranded wire solid and the wire breaks at teh solder joint. This is the way I solder terminals to get around the problem. Crimp, then solder the tip where the stranded wire peaks out. This way the stranded wire is intact where the wire enters the terminal and the connection has a good solder joint. The best of both.

I did not know this for many years but the stiff insulation skirt on the terminals is meant to be crimped to the wire insulation. The moon shaped crimp on the tip of the ubiquitous crimping tool is for the stiff insulation skirt. This keeps the wire from moving and breaking.

Tom
 
well for the sake of argument....my two cents. I have always tinned the wire, dipped it in petroleum jelly and crimped it on. Several connections on my bike done this way are 30+ years old and I have never had a failure. Yet! "knock on wood". I use rosin core fine radio solder. If the wire is blackish looking it won't tin and should be replaced. A small iron works way better than a soldering gun.
 
The problem with solder is it makes the stranded wire solid and the wire breaks at teh solder joint. This is the way I solder terminals to get around the problem. Crimp, then solder the tip where the stranded wire peaks out. This way the stranded wire is intact where the wire enters the terminal and the connection has a good solder joint. The best of both.
Tom

Cool beans - just have to make sure that you don't put very much soldier on as it will travel up the stranded wire (invisible to you).
 
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