Hard to use solder

[Focalized]

The one on the left is what I use most ever. Very easy. The other two are difficult to melt onto any part or board. Globby. They don't seem all that different. I have solder paste but have only used it to help with dedolder braid. Just wondering best way to use and not waste it.

[idy]

Funny that you can't read percentage tin/lead or whatever on the two you don't like. Does the other side of the spool tell more? the middle one especially "63% diameter?" "63% DT?" Deuterium?

[Focalized]

It's 63/37. The DIAM is just bad labeling. Calidad means grade I think.

[Focalized]

Found this.
"Trinity 63/37 (1mm) Solder. 63/37 ratio is a Eutectic alloy of Tin Lead solder. As such it melts at a temperature that is lower than each of its constituents, and at a very precise single temperature rather than a range of temperatures. In the case of 63/37, it is 183 degrees, where 60/40 melts around 188 degrees. As the melting point is a single temperature it will transition fast than non-Eutectic alloys which means lower chances of dry joints."

I have adjustable solder temp but no reading. Maybe I need to go colder I have it just above halfway usually. Don't see how 5 degrees makes such a difference.

[mozz]

Are they lead? It doesn't say? They could be lead free. Anyway, you need to go hotter if it's not melting. That all being said, you will never find china branded solder on my benches. They are saving the lead for the dog food and garlic they export.

[Focalized]

Cheap as can be. It melts on the tip just hard to stick to parts. I'd only try it again on jacks if I have to. I'm sticking with the left brand or similar.

[R.G.]

Found this.
"[...]. In the case of 63/37, it is 183 degrees, where 60/40 melts around 188 degrees. As the melting point is a single temperature it will transition fast than non-Eutectic alloys which means lower chances of dry joints."

I have adjustable solder temp but no reading. Maybe I need to go colder I have it just above halfway usually. Don't see how 5 degrees makes such a difference.

It's like, science. If it doesn't get hot enough, it doesn't melt. 60/40 will not melt at 183C. It starts getting slushy, getting slushier over the next five degrees, until it's all liquid at 188C. Those five degrees are baked into the elements tin and lead, so it makes a huge difference.

Going colder is nearly always a bad idea with solder.

I once proved my house plumbing was done with 50-50 lead solder instead of lead free solder by conducting a temperature melting test. I got blobs of the solders they actually used, and snibbets of known 50/50, 60/40, and 63/37, put same sized blobs on a steel plate over a propane flame, then heated gently. The 63/37 collapsed suddenly into a drop; the 60/40 slooooowly got liquid a bit later; the unknown blob and the known 50/50 melted slushily at the same time.

A too-cold iron will never get the base metal being soldered up to or over the melt temp of the solder, so good joints can't form.

What you're describing seems like the two bad actors are either not really electronic solder, certainly not 63/37 tin lead, or you're not cleaning and fluxing well, or that they are contaminated with other metals.

My time is too valuable to worry about low quality solder. I personally would dispose of the bad actors and get known-good fresh 60/40 or 63/37.

[Phend]

One of the ingredients is China, hence you don't know what is in it. I bought a roll of China crap and tossed it out (Recycled). Fortunately years ago I bought a roll of radio shacks when they were closing a near by store. Rob, I believe,  once said that China melts down old circuit boards, sorts out the metals and..  

[GibsonGM]

I got a huge roll of 60/40 from Smallbear years back, .040", by a company named "AIM".  Never an issue, flows smooth as silk.  I also had some of that crap stuff, out it went. Not worth messing with if it's not cooperating with you...we work hard at getting this stuff right, don't want to be fighting the solder to boot!

[moid]

I remember when I first started soldering I made the mistake of buying something that in the UK is called Plumber's Solder - which was hard to melt, then when it did melt it was more of a gritty paste than a fluid... awful stuff - I soon realised I had the wrong stuff and bought some 60/40. Maybe some of the reels in Focalised's photo are that stuff?

[Focalized]

To be fair the Yi Lin solder is Chinese too I think and is very good. I'll throw it in my Amazon orders over the years. You'll get crap straight from China for sure though if you take a risk.

[Focalized]

I forgot about Smallbears pound of solder for $25. Should just go with that if I make a bigger order.

[fryingpan]

This has long been a question of mine. I have a relatively cheap soldering station from Amazon. I don't expect it to be high quality, but somewhat better than the usual soldering irons you get at the local shop or whatever. I use lead/tin solder (60/40) and I set the temperature dial about halfway. Nominally it's 350°C (I honestly don't think it is). It is probably much too high, but this way I never have to worry about solder not melting. Should I set it lower? A hot soldering iron could damage components, but on the other hand, I only need to apply it for a second or so.

[duck_arse]

I use lead/tin solder (60/40) and I set the temperature dial about halfway.

lead/tin is not the same as tin/lead.

[R.G.]

This has long been a question of mine. [...] I use lead/tin solder (60/40) and I set the temperature dial about halfway. Nominally it's 350°C (I honestly don't think it is). It is probably much too high, but this way I never have to worry about solder not melting. Should I set it lower? A hot soldering iron could damage components, but on the other hand, I only need to apply it for a second or so.

You're doing it right. High heat for just a moment or two is great. My temperature is set to the highest temperature that doesn't make the tip oxide up too fast and need re-tinning.

Soldering is a coordinated manual/visual skill that manipulates a source of high heat and the speed at which the heat flows into the parts being soldered. Heat takes time to flow through things, so the trick in soldering is to get in quickly to the one spot you want to heat, get it up to solder-flowing temps, and then to get the heat source away before you overheat something. Once you develop that skill - as you clearly have - you will rarely if ever overheat something.

OK, it's the morning for too much information... 
Here is the quick intro to tin-lead solder metallurgy. With 0% tin (that is, pure lead) it melts at about 340C. As you add tin, the temperature for fully-liquid, not pasty/grainy, comes down. At exactly 63% tin and 37% lead, the temperature is lowest, and there is no slushy/grainy state. It's either solid, or liquid, period. The bigger the pasty/slushy range, the better your chances to move things before they get fully solid and make a cold/cracked joint. I was a little surprised at the diagram labeling 35-tin, 65-lead as plumber's solder. Our plumbers used 50-50 back when they were allowed to use solder with lead; that has been outlawed in the USA for a couple of decades now.

https://www.researchgate.net/figure/The-lead-tin-Pb-Sn-phase-diagram-with-three-different-solder-compositions-marked-out_fig1_337367336

Edit: forgot to add  - this is for only tin and only lead; if you mix in other metals, the phase diagram can get very complicated and the temperatures and liquid/pasty/solid areas can get very complicated.

[bloxstompboxes]

I got a huge roll of 60/40 from Smallbear years back, .040", by a company named "AIM".  Never an issue, flows smooth as silk.  I also had some of that crap stuff, out it went. Not worth messing with if it's not cooperating with you...we work hard at getting this stuff right, don't want to be fighting the solder to boot!

AIM is probably my favorite and half the price of Kester.

[mark2]

AIM is probably my favorite and half the price of Kester.

Do you recall where you buy it? I always buy Kester  because it's easy and I know it'll be fine, but I wouldn't mind saving some cash.

[Focalized]

The smallbear stuff is AIM but they show less than 20 stock. I need to commit to a couple Wah pots that aren't too expensive so I'm going to try that stuff again.

[bloxstompboxes]

AIM is probably my favorite and half the price of Kester.

Do you recall where you buy it? I always buy Kester  because it's easy and I know it'll be fine, but I wouldn't mind saving some cash.

Probably on amazon. Looking now shows several different rolls on sale. For example, AIM 1lb of 60-40 .032in diameter is now $23.83 vs the usual $28.95. Kester 1lb of 60/40 .031in diamter is $38.02.

So maybe not half at the moment but around $15 cheaper nonetheless.

[mozz]

You can get Kester solder a lot cheaper than that. How long is a pound going to last you, 1 week, 5 years? I've burned through a lot but i have 2 soldering stations set up. Glad i buy most at flea markets and yard sales for $1-$5. Check Ebay. I would say $25 at the most with free shipping.