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Discussion Starter #1
I did a search and didn't quite get the answer I need.

I have the soldering gun, solid core solder etc..... even have a pencil .

So: How in heck do I keep the wires in place as I heat them up to the point where the solder can be applied? 3 hands?

I've done two simple wires flat on a piece of wood... press them together with the gun and yes.

Soldering wire to so connection inside a loco is a new challenge for me. Any ideas?


gg
 

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1. make the wiring the mechanical connection, not the solder. This means crimp the wire or put it in a hole.
2. secure the rest of the wire so it does not move while soldering, tape, clamps, a brick, whatever. Movement during soldering will give you a cold solder joint, which will fail.
3. you want the thing to be soldered in a place so it does not set fire or burn something else.
4. Find a friend and have him show you, this is much more easily explained in person.

Regards, Greg
 

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I agree with what greg said, but sometimes you can't make a mechanical connection.

Pre-tin each part to be joined--put solder on each part, then bring them together however you can manage with the iron ready to go. Sometimes. It really only takes a second wth most parts.
 

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I would suggest you find a way to make a mechanical connection, solder WILL fatigue when flexed.

But, if all else fails, then clamping the wires with a soldering "helper" will do it, or weights on the wires, etc, just make it so they do not move.

Regards, Greg
 

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Discussion Starter #5
Now I get it and I'm not nuts.

I like the idea of presoldering. and naturally being able to crimp would keep it together.

I will need to practice ! Anyone want to lend me YOUR locos?
to practice on?????

gg
 

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Sometimes when I'm faced with the challange of soldering a bunch of wires together that I cannot twist together for whatever reason (e.g., too short, or no space), I'll use a clothes pin (or such) to hold them together enough that I can solder them. And yes, it does help to have these wires "pre-tinned" so they are ready to go at the touch of the iron.
 

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I did a quick search on the web under "soldering techniques". Lots of info out there. A bunch of really amateur U-Tube junk, but here is one by Popular Mechanics that illustrates the basics fairly well. How to solder wires

Whenever I have a bunch of wires (like 3 or more) that need to go to the same screw terminal (which will only hold one or two wires at most) I tend to use a "wire nut". Just twist the whole mess together, along with the one wire that will terminate on your screw terminal, and screw on the wire nut. They are easy to use and you can also easily undo the mess if you need to. The downside, is that is usually the failure point. Not a real reliable connection.


For simply splicing two wires together, I usually just use a lap joint (as described above). Just tin both wires, hold one with a 3rd hand device, and hold the other next to the first while you apply heat and solder. No movement while cooling, or you will get a cold solder joint (dull looking). Cover the joint with heat shrink tubing (that you put slipped over one of the wires before soldering). Mechanical joints are much better, but as long as you have a good solder joint (nice and shiny), the lap joints work fine for me. (We aren't putting this solder joint in space).
 

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Discussion Starter #8
That's it...

Greg... I need to resolder your locos...

can you pls lend them to me?



gg
 

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Sacrificial wood clothes pins can work (keep water handy to duck them in if needed) or stainless steel hemostats (its difficult to purposely solder stainless).

-Brian
 

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GG states: did a search and didn't quite get the answer I need.

I have the soldering gun, solid core solder etc..... even have a pencil .


What is solid core solder? If solder is solid, it would not have a core!!!

Did you mean rosin core solder?

I find it easier to solder with the 'older' rosin core solder I have on hand as it has more lead in it and flows at lower temperatures than the 'new' rosin core solder.
 

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Discussion Starter #11
Posted By Dan Pierce on 03/14/2009 4:27 AM
GG states: did a search and didn't quite get the answer I need.

I have the soldering gun, solid core solder etc..... even have a pencil .


What is solid core solder? If solder is solid, it would not have a core!!!

Did you mean rosin core solder?

I find it easier to solder with the 'older' rosin core solder I have on hand as it has more lead in it and flows at lower temperatures than the 'new' rosin core solder.








I got the stuff with no liquid in it ... rosin...
 

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For soldering wires, you want resin core solder, often called electrical solder.


1. Fasten the wires together securely so they don't move.


2. Heat the wires till the wire is hot enough to melt the solder.


3. Touch the solder to the wire away from the iron. It will flow toward the heat.


If your piece of solder, or your iron sticks to the wire, you don't have a big enough iron. 


If the solder rolls off the wire or forms beads on it, your wire isn't clean, or solderable with the resin.


If the wires wiggle before the solder freezes, you'll get a "cold" joint and the solder will look dull and rough. This is not good. 
 

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GG

Wire solder comes in many sizes (i.e. diameter), also various alloys of lead, tin & antimony etc. Most but not all wire solder for electrical and/or electronic use is manufactured with rosin or resin contained in the core of the wire, which is used as the flux...

e.g. five-core solder


Rosin-Core leaves a nice clean finish on your joints on pc boards where Resin-Core leaves blobs of solder flux. Resin core is for wires and coil lugs that may be less than perfectly clean and the resin aids in bonding the solder like flux.
 

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Discussion Starter #14
Gents, lots of information and thanks:

I went down to my trustworthy tool box and can confirm that I bought Rosin Cor Silver Bearing Solder - 0.022"

Bit of background: I was prepping my 14 gauge wire and mounting banana plugs. Despite minutes of heat gun I really could not get the wire connection to melt the solder...


So; I went to the garage and pulled out my lead crimper and 5 minutes later I had a perfect mechanical joint.


So I need to practice that get the techniques that you outline above down pat.

thanks for the support.


gg
 

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GG

How about the tip of your soldering gun/iron, clean and well tinned? If not you'll have poor heat transfer.
 

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Discussion Starter #16
Just heat scored:

Should I "tin" it with solder?

gg
 

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By all means the tip of your soldering gun or iron should be 'tinned'. Do that by filing until the copper is shiny. No one said, and it's fairly a personal choice, but I always have a square can of rosin flux to hand, here's why: once your iron's tip is shiny brite copper, you start heating it. It will tend to oxidize as it heats, so stick it in the can of flux. (As soon as smoke starts to come off the tip, you know it's getting near to soldering heat. Keep tip fluxed. Then dab your solder onto it, until it takes. Dab a big enough glob to shake it off and leave a soldery-looking tip.

Another reason to keep the tin of flux handy is, your iron/gun will tend to collect ash while in use, you can stick it in the solder tin (paste) and wipe it on a mildly damp rag or sponge and keep right on going until it's time to tin it again, which should be hours and hours.

Also, lots of new solderers don't use a big enough iron or gun. If you're doing 14ga wire, you want ~ a 100watt iron minimum--and I'd go bigger-- with a fair-sized tip, because the wire connection sucks heat out of the tip, and you need the 'thermal mass' so to speak. If using a gun, you need a bigger one so the tip gets hotter.

Les
 

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Yes sir, the term "tinning" when used in reference to soldering means to coat with a thin coat of solder. However, only after making sure that you've cleaned it well. Be careful with what you choose to clean the tip with. If it's a plated tip (and today most tips are) and you use something that is too abrasive you will destroy the plating, which in turn will severely shorten the useful life of the tip. Because the tin in the solder and flux over time will corrode the copper. Also, if you have a temperature control use the lowest temperature you can to get the job done, the higher the temperature the faster oxidation. Correct tip maintenance becomes an even more important issue with the introduction of lead-free solders. Higher temperatures and higher tin content solders will be more damaging and corrosive, leading to shorter tip life.

Most soldering tips are made of copper and then plated with iron, which in turn is plated with nickle or chrome except on the wedge shaped end which remains bare iron (solder won't stick to nickle or chrome). To keep the bare iron from oxidizing is why the tip needs to be tinned and kept clean. In my experience most of the trouble with soldering comes from the user failing to properly clean up the soldering iron/gun after use.
 

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Solder containing silver has a higher melting point than solder without silver. It is used for high quality and RF. Most osciloscopes used silver solder for all connections.
 
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