What's the largest solder wire you have used?

[KL27x]

I have been assembling, in small volume, one of my projects that has quite a few thru hole connectors on it, along with a large number of SMD parts. Assembling the thru hole stuff makes my 0.031" solder disappear like fishing line with an angry Marlin on the other end.

I have been thinking of using something bigger, anyway. So I bought a new roll and have been using 0.062" rosin core solder for a week or so, now. In one word, amazing. I'm no longer in fear of developing carpal tunnel syndrome from dispensing solder wire. It works just as good for the way I do SMD, as well.

So what's the biggest solder wire you have used for general electronics work? I don't even know what the larger sizes are, if any.

 

[tautech]

Old CINEVOX 2.2mm

[wraper]

8 mm . I still have some left.

[KL27x]

Old CINEVOX 2.2mm

Ok, that's big. According to my calculations, 0.062" solder is 4 times as much solder per foot as 0.032". 2.2mm would be almost twice as much, again. 7.8x the solder.

Ok, that's pretty big. Would you even consider using that stuff for board-level/general use? I'm pretty sure I will be using the 0.062" more than any smaller size, period.

8 mm

Ok. Using 0.031" as the standard, 8mm would be 103x as much solder per foot, lol. I think you need a Metcal with the "shovel" tip or a blow torch for that stuff, right?

[Augustus]

8 mm . I still have some left.

Whoa, that's huge...  What did you use it for, plumbing work?

[tautech]

Old CINEVOX 2.2mm

Ok, that's big. According to my calculations, 0.062" solder is 4 times as much solder per foot as 0.032". 2.2mm would be almost twice as much, again. 7.8x the solder.

Ok, that's pretty big. Would you even consider using that stuff for board-level/general use? I'm pretty sure I will be using the 0.062" more than any smaller size, period.

No.
Large lugs, riveted terminals and repair/rework of large TH stuff only. Rarely use it, just handy to have. 

PCB, SMD or TH, 1 or 1.6 mm (40 or ~60 thou) is plenty fine for my needs.

[wraper]

8 mm . I still have some left.

Whoa, that's huge...  What did you use it for, plumbing work?

So what's the biggest solder wire you have used for general electronics work? I

^^^
for this.

[KL27x]

PCB, SMD or TH, 1 or 1.6 mm (40 or ~60 thou) is plenty fine for my needs.

Oh, ok. 1.6mm = 0.062"
This appears to be pretty close to ideal for me, too. I am using my standard go-to combo SMD/thru-hole tip, and anything significantly bigger, I'd be melting tip-shaped pieces out of the wire.

[KL27x]

I found it satisfying to see solder wire being fed to joints and simply go away.

Well, that is great and all. When I have built a precision high speed motorized wire-feeder, maybe I will use the thin stuff for everything! Until then, I find that solder big enough to slice into rosin-filled donuts is simply amazing.

[Sbampato12]

I like to use 0.5mm for SMD, 0.8mm for PTH and I have a spool of 1.0mm for other use (rare for me).

[SeanB]

Got a bar of 6mm by 6mm for terminals and lugs that need soldering, like those on battery terminals, where corrosion of the wire is going to cause a failure before flexing does. Otherwise I buy 1kg boxes of 2mm rod for copper piping in airconditioning, though it also is great for gas piping as well, a lot stronger than regular plumbing solder. Even though those are self fluxing on copper, I use them as general purpose rods as well, using borax as a flux. I buy that in 20kg bags for other uses, though it does make a good metal brazing flux.

[jwm_]

I much prefer thicker solder to thin. The reason is that tactile sensation is as important as visually seeing what is going on for me. With the super thin solder dave recommends, i could be melting against the iron, missing the joint completely and just bunching it up, or whatnot and it feels identical, like nothing.  With thicker solder there are very distinct feels to missing the joint completely, hitting something not hot and feeling the solder bend, having it just melt against just the iron (it has the resistance to pushing you expect from melting, but it slides laterally up and down way to easily), or the nice thunk of the tip of the solder just hitting between the pin and iron wedging it in place just before the steady resistance of melting.

Another huge advantage for me is it is much easier to position my hand such that i can precisely control the movement of solder over the half a cm or so max range i'd need  with just fingertip movements and my hand resting solidly on the table than it is to constantly have to play out more thin solder, moving my whole hand or all my fingers to get enough of the thin stuff in there. I have much more precise control with thick soder than thin under normal usage. That 1cm or so range of movement is a sweet spot  where  hand can be resting in a stable position and just he fingertips move is great for tactile feedback and good precision.

[nanofrog]

.062" is the largest I have on hand.

...I find that solder big enough to slice into rosin-filled donuts is simply amazing.

[T3sl4co1l]

Um...

Uh...

Maybe 12mm-ish???

Kind of dubious though.

What I was doing was using some cast ingots of zinc alloy (roughly 1/2" across, oblong shaped, various lengths) and rubbing them against aluminum pieces, heating everything with a torch.

When you get the aluminum to just over the melting point of zinc, the zinc bar smooshes into the surface as it turns to metallic goo, while the solid part scrapes against it, at least partially removing the aluminum oxide layer (it also tends to melt under the skin, creeping along the metal surface itself, making it even easier to scrape the oxide away).

Soldering vs. brazing is a matter of definition; zinc's melting point is right on the edge of the traditional definition.  A more nuanced, metallurgically motivated definition would call it brazing (the zinc tends to seep into the base metal itself, forming a very strong bond).  Although I would dare argue (from the same basis) that soldering pure lead with 60/40 is also brazing (the solder creeps into the lead base).

Of course, if we allow such things, someone is sure to come along and claim they were using solid bricks of lead (100mm+?) to fill and bond a steel box or something...

On a more serious note, I've used regular plumbing solder (for actual plumbing, imagine that), which is something like 2-3mm (no flux core).

I currently use 20 mil for electrical soldering purposes.

Tim

[tautech]

Of course, if we allow such things, someone is sure to come along and claim they were using solid bricks of lead (100mm+?) to fill and bond a steel box or something...

Tim

Like my buddy with a timber piling business that made a lead filled drop hammer using lead ingots......2 tonne of them. 
Took a week to cool. 

[KL27x]

So far the only drawback I have encountered for the 0.062" solder is....

With the 0.031" solder, I can more easily get a LARGER bead onto my bevel tips, when desired. With the 0.062", I am more prone to crossing the line where the bead gets too big and falls off, lol. But that's a relatively minor drawback which may decrease with familiarity.

I much prefer thicker solder to thin. The reason is that tactile sensation is as important as visually seeing what is going on for me. With the super thin solder dave recommends, i could be melting against the iron, missing the joint completely and just bunching it up, or whatnot and it feels identical, like nothing.

Dave has also expressed a strong preference for chisel tips. Maybe there are some different techniques that people pickup with chisel tips. I bought a chisel tip to play with, and I keep it handy, just in case I crack the code one day. I haven't figured it out, yet. For me, the chisel tip has been worthless, so far. It'll get the job done. Slowly. With the least ergonomic wrist angles imaginable. I have more use out of a knife tip than a chisel, and that's pretty rare. Specific rework, anyhow.

Never really gave a thought to the tactile feedback. For me it's the feed rate and the droopiness. With thicker solder, you can hold a "bar" of solder a good 6"+ from the tip and solder an entire row of double pin headers or whatnot, without stopping to grab more solder. I try to work from right to left, where it would otherwise not matter... so my left hand doesn't have to move as much as the solder disappears. For SMD, my left hand is holding tweezers, not solder, so I don't miss the thin stuff, there, either. Well, other than the aforementioned problem.

[John Coloccia]

I use .025 for most PTH and SMD, and .031" for everything else. The problem I have with larger sizes is if you don't add flux, there's just not enough flux that gets into the joint for the amount of solder you need. If you're adding flux, then it doesn't matter.

[PTR_1275]

I use 0.8mm on my bench where I mostly do electronics, on my other bench I use 1mm, then when I need thicker I make a solder rope out of multiple strands of the 1mm. It means I don't have to have lots of different solders in stock and I make the rope to the size I need for the job.

[KL27x]

I use .025 for most PTH and SMD, and .031" for everything else.

What is everything else?

The problem I have with larger sizes is if you don't add flux, there's just not enough flux that gets into the joint for the amount of solder you need.

Really? I think this might be brand specific. I'm sure larger solder wires can have "enough" flux in them.

[John Coloccia]

I use .025 for most PTH and SMD, and .031" for everything else.

What is everything else?

The problem I have with larger sizes is if you don't add flux, there's just not enough flux that gets into the joint for the amount of solder you need.

Really? I think this might be brand specific. I'm sure larger solder wires can have "enough" flux in them.

The flux is in the core. If you use so little that you barely even get to the core, you won't have any flux in the joint, especially if your solder end is melted over burying the core even further.

[KL27x]

Aha. Now that is a very good point. Does multi-core solder not fix this problem?

What is everything else?

Ne'ermind. I guess I forgot that people have to solder wiring and other things. LOL.

[John Coloccia]

Aha. Now that is a very good point. Does multi-core solder not fix this problem?

What is everything else?

Ne'ermind. I guess I forgot that people have to solder wiring and other things. LOL.

I don't know. I was wondering about that myself, actually. I've never tried Multicore (I think that's Ersin, right?). It doesn't seem to be particularly popular in the US, where Kester rules, but I seem to see it popping up elsewhere.

[KL27x]

You must be psychic. I'm using Kester single core solder, lol.

[wagon]

For most work I use 0.8mm, but I do use 1.0mm a lot too.  I also have 0.3mm and 0.5mm, but I don't use those much.  I have a scrap of about 2mm somewhere, I use that for repairing blown thermal fuses in ancient electric fence units (they run it through a hollow wire-wound resistor).

[nanofrog]

The problem I have with larger sizes is if you don't add flux, there's just not enough flux that gets into the joint for the amount of solder you need.

Really? I think this might be brand specific. I'm sure larger solder wires can have "enough" flux in them.

Sounds like large voids are the likely culprit IMHO, and solder quality definitely has an effect here.

But keep in mind, that there's different amounts of flux available for a given alloy and flux type. There's 1.1% (also referred to as P1 or Core 50), 2.2% (P2 or Core 58), and 3.3% (P3 or Core 66) by weight for rosin types of flux for example. The smaller amounts will leave less residue (cosmetically pleasing when skipping cleaning), but is really only suited to clean parts and boards to start with given there's so little flux.

Does multi-core solder not fix this problem?

Multicore is meant to reduce the size of voids in each flux core. And the smaller the void, the smaller the splatter. FWIW, I only find it an issue with larger diameter solder wire, such as .062" (mine pops like hell). I wouldn't worry about it with smaller diameters.

Another method is to feed solder into a solder wire cutter/perforator (cuts a slit/punches holes down the length of the wire so the gas can escape without "blowing out" molten solder & flux). FWIW, Hakko offers such units, and there are copies available.

I've never tried Multicore (I think that's Ersin, right?). It doesn't seem to be particularly popular in the US, where Kester rules, but I seem to see it popping up elsewhere.

Multicore was an Ersin trademark (US company), but it's currently owned by Henkel of Germany. They've shifted manufacturing from the US to other locations, such as Malaysia, and it's become a more European brand (better availability there than in the US, though you can still get it). Stannol is another quality brand that's rare in the US.

Multicore has also reduced their lead based offerings, while Kester, AIM, and Indium haven't. Combine this with better availability, these other brands have a larger market share IME (Kester having the largest piece).