Cascade Crew

[Xophertony]

Crew,
I am in need of advice and instruction. I'm trying to solder wires on my car. The issue I am experiencing is that I cannot get the solder to melt to the wires, or the gun. The wires will be hot enough that I cannot hold them even through the insulation for 3-5" on either side of the joint, but the solder will not melt. I watched some instructional videos on youtube today, and tried to "tin" my tip before starting, this was a brand new tip mind you, and the solder just melted and beaded off. so I held the trigger down for another minute or so and tried again. Same result. I cleaned the tip, dipped in flux, same result.

I have two soldering guns, one is a "gun" style dorman, brand new. The other is a select-able 15W/30W "pin" style from radio shack, a few years old. The tip was a bit old, and probably "oxidized" which I heard from youtube is bad, so I took a fine file and cleaned it up before proceeding. Today I was using non flux core solder with separate flux, which I have never used before. But I have had the same result with flux core solder in the past. My garage was a nice warm 60* today as well.

Do I need a better soldering iron? If so which one?
Do I need to let the gun warm up for 30 minutes with a rubber band around the trigger?
Do I need to give up and buy a brand new Kia?

Thanks for your advise crew.

[chevymad]

Lots of flux Tony. I let my iron get hot and then dip the tip in the flux. It will smoke. Now touch some solder to it and it should stick and spread on the tip.

What type and size of solder are you using? Silver based solders make a stronger joint but are much harder to melt. Thick solders will work with the gun but not with the pencil.

Also what size wire? 10 gauge is about max with a soldering gun. The bigger the wire the more the heat is transferred down the wire. You want just the bare part of the metal to get hot enough to melt solder, not 5" of wire that's almost hot enough. You want the tip of your gun/iron to be hot before you touch the part. You don't want it to be trying to heat up both pieces at the same time. Bigger tip for bigger wire. That way you have more mass heated up before touching the wire and it cools down less quickly. You're trying to keep the heat very local to where you are working.

[aaron_sK]

What gauge of wire?

Not being able to hold the wires due to heat means nothing. I have had insulation melt and drip off from soldering with too small of a gun. You want to heat the ends quickly and not give it a change to sink into the entire wire.

*Edit:

Haha, beaten by Brandon, and with the same advice.

[rjmcgee]

Go get one of these Tony, works great!

http://store.snapon.com/Guns-Gun-Soldering-150-400-Watts-P640465.aspx

[MrMike98]

OK this is something i know about-
I have been soldering (at home and work)for 50 yrs at least..

first-CLEAN- the joint u are working on must be CLEAN. no oil dirt rust corrosion etc....i try and cut back wires so i start with fresh clean ends

Use ONLY rosin core solder- silver solder needs an acid flux-bad-bad for wiring etc.... good for cooper pipes

iron tip must be clean and tinned..u can use a little sand paper to clean tip. i do this hot then immmediately put a little solder on tip to tin it.... then as u go- wipe tip often (wet spong) and retin.

machanically bond wires(twist them together)- heat junction untill solder will melt on the side opposite the iron(add a dab of solder between iron and wire to aid heat transferr to wire)--solder should at that point wick up into joint-no extra solder will be needed.. if it balls up and runs off-u need more heat or the joint is dirty....
you should be able to do this without melting wire insulation(but that might take some parctice)

use the pencil iron on hi setting 30w is plenty- I do not like the guns-to many issues-

thats all i got to say--


practice on fresh clean wire on the bench-

[Xophertony]

it was a 12 or 14 guage wire. I was using solder that was very thin. If i was to measure it in wire gauge I would say 18 or 20. It was not silver solder to my knowledge, although I do have some of that. I was able to get success later with a new tip for the pencil. I was dipping the tip in flux first, and then "tinning' the tip. (Brandon, should I be putting flux paste on the wires before I start heating them?) I was able to get it by coating each wire on it's own, than soldering them together. It still seemed lkike the solder i put between the two wires did not penetrate properly. (is this the right technique to use?) I think the issue is that I need a bigger tip to transfer more heat when doing multiple wires. Radio Shack (they suck) only had the pointed ones, not the flat-head style ones. The gun I bought is defective, I noticed that it does not stay on, but rather goes in little bursts. Probably a defective trigger switch.

Rodney, that is a nice unit you have there (snicker), I may get one of those. does anyone have any other awesome solder equipment recommendations?

[chevymad]

Flux on the wires can help. Won't hurt a thing to dip the ends before you start.

With lead use being more and more restricted they're using more silver in electronics solders. I use a silver bearing solder for some circuit boards I've built. It's only 0.015 diameter. Easy to use the first time but hard to heat up enough to remove. It is rosin core as well.

For wires like you're doing I use a 60/40 rosin core 0.062 diameter.

[aaron_sK]

[Xophertony]

Thanks for the validation Aaron.

[Alphius]

[QwkTrip]

Need to change your equipment and technique. I think you're trying to heat bare wire and make the solder melt into it. That's why your wire is getting so freaking hot and you're ruining the insulation and setting yourself up for future electrical shorts when insulation breaks down. The best heat conductor into the wire is the solder itself so you need to use it to carry heat and make a quick solder before the heat spreads down the wire and ruins the insulation. A good solder wicks into the wire and happens quick without leaving a big blob hanging from the bottom.

You need heat and lots of it. For automotive wiring I use a 100/140W gun with a wide flat tip. Throw away the solder you have and use rosin core solder, like MrMike98 said. Some people twist wire pairs together and some try to tin side-by-side. I mesh the wires by sliding the strands together end to end and then give it all a twist so it will hold. This will produce the most contact area for lowest electrical resistance, and produce the strongest joint. I also use a soldering vise so the wires are held in place when I work and I have both hands free. I let the iron get red hot and then make contact to underside of wire. There's a sweet spot on the tip where there is a lot of heat and I want that spot at the wires. After a few seconds I touch the tip with solder and let a little bit wick into the wire but I don't finish the joint because the wire isn't hot enough yet. I move the solder to top of wire (opposite the gun tip) and wait for the solder to wick into the wire to finish the joint. Always rub the gun tip on a wet sponge immediately while the tip is still hot.

Keep in mind the soldered region becomes brittle and can break if not supported. Always cover it with shrink wrap and extend the shrink wrap at least 1/2 inch past the soldered area. The shrink wrap will insulate and provide support for the wire. I use shrink wrap with a glue inside that melts and makes it water tight.

[rjmcgee]

This is what I've been using lately,

[aaron_sK]

[Xophertony]

[rjmcgee]

Good heat gun, I have a Milwaukie. Use good crimpers, then just heat until the heat shrink shrinks and the solder melts. Phillips is the brand I bought and they are almost $1 each. Gor turned on to these when I was trucking and we used them to fix lights, the only thing I've seen so far that will stand up to the de icer that the state uses. Everything else would get ruined in months if exposed

[rjmcgee]

Also I got these at Fleetpride, may be way better deals on line but I haven't looked.