What does "60%" on solder mean?

I have an old roll of solder- not sure of its provenance, probably belonged to my late father in law- and it's marked 60%.... what does that mean?- Something to do with its composition I guess- lead?

Corollary to that: I have a reasonable soldering station (no name, Chinese, but seems pretty good) with adjustable temp. For that solder, is there a recommended temp?

(I've been soldering since about 1962 when I dropped hot solder on my bare leg, so I know it's hot but never really thought about the actual temperature. My late Dad had an Adcola back in the day...)

And final question: if I were to go buy a new roll of solder today, what should I ask for in terms of composition and what temp would that be soldered at?

Edit.... I suppose I should have Googled first... 60% is 60/40 lead/tin and i melts at 360.

I think solder used to be, or still is, 60% tin, 40% lead.

http://en.wikipedia.org/wiki/Solder#Lead_solder

JimboZA: I have an old roll of solder-

May want to send it off to a recycler. Acid core is not too good for irons, electronics, everything except old plumbing. Unless you know it to be rosin core (or can find a way to test from the Great and Wise Gorcle) best not to ruin the hobby things.

And final question: if I were to go buy a new roll of solder today, what should I ask for in terms of composition and what temp would that be soldered at?

Lead or lead-free?

Ok so seems the 60/40 comp is probably still the case, but the rosin vs acid core is the thing to watch?

The old roll doesn't say either way, so it probably pre-dates the time the rosin core came in....

Maybe I should just get a new roll.

My daughter bought a kit of stuff from the faculty at uni the other day- cutters, pliers, screwdrivers etc. They had the option of an el-cheapo iron or one of 2 more expensive ones (I forget the makes or price, but iirc the better ones were some 5x the price). I made sure she got one of the expensive ones. Also got a decent dmm with it, so she's well set for a while. Plus I bought "us" a 'scope last year, she can take that when she's past the first year or so.

She got a roll of solder too. I'll ask her what it says on the label.

Yes, no acid core unless you are soldering water pipes together. Rosin core solder, the thinnest you can get. I use 23 gage (0.025" diameter). http://www.mgchemicals.com/products/solder/leaded/sn60-pb40-4890/ I buy one pound rolls for soldering thru hole parts onto boards.

Unless you need ROHS compliance, use 60/40 solder.

http://en.m.wikipedia.org/wiki/Restriction_of_Hazardous_Substances_Directive

Weedpharma

weedpharma: Unless you need ROHS compliance, use 60/40 solder.

http://en.m.wikipedia.org/wiki/Restriction_of_Hazardous_Substances_Directive

Weedpharma

I prefer my 63/37 for fine jobs. It seems easier to get perfect joins as the solder has a higher melting point and solidifies almost instantly when heat is removed.

Hmmm well I was looking at my preferred supplier site and their solder is this lead free. I'm going there today anyway, so was thinking to get a roll of that. They have .3 .5 and 1mm, thought I'd go down the middle with .5?

pYro_65: I prefer my 63/37 for fine jobs.

https://www.google.com/#q=eutectic

weedpharma: Unless you need ROHS compliance, use 60/40 solder.

http://en.m.wikipedia.org/wiki/Restriction_of_Hazardous_Substances_Directive

Weedpharma

NO!! Lead is highly poisonous, avoid using lead unless you possible can. Old lead-rich electronics rotting away in wasteheaps is poisoning water supplies and causing lots of nasty and expensive issues for those that have to deal with the mess.

There is absolutely no need for lead in hobby electronics, lead-free solder is perfectly usable if you get the tin/copper/silver stuff. Its more expensive but you don't use very much - the price is a tiny tiny fraction of the cost of the whole project!

MarkT: lead-free solder is perfectly usable if you get the tin/copper/silver stuff.

That happens to be what I got...

MarkT: NO!! Lead is highly poisonous, avoid using lead unless you possible can. Old lead-rich electronics rotting away in wasteheaps is poisoning water supplies and causing lots of nasty and expensive issues for those that have to deal with the mess.

There is absolutely no need for lead in hobby electronics, lead-free solder is perfectly usable if you get the tin/copper/silver stuff. Its more expensive but you don't use very much - the price is a tiny tiny fraction of the cost of the whole project!

No lead is not. It is inert. I have a friend who was shot in the back with a .22 bullet when we were freshmen in highschool. We are now past 75 years and he is still carrying it and is as healthy as I am. Many WWII and other veterans are carrying lead in their bodies.

Red lead paint was used forever in paint in water storage facilities. People drank the water for generations. The white lead oxide used in house paint for generations will give up it's lead content when digested.

Any lead, bullets, etc, will become coated with lead oxide and that will protect the metallic lead from becoming dispersed in the environment.

If lead is poisonous, then vast parts of Illinois, Missouri and other midwest states are uninhabitable. Lead is in all their soil.

Paul

I have a friend who was shot in the back with a .22 bullet when we were freshmen in highschool. We are now past 75 years and he is still carrying it and is as healthy as I am.

Specious reasoning rears its ugly head. Lovely.

Well, I have a (squirrel) friend who was shot in the back with a .22 bullet when he was a few years old. He is stilling carrying it. He is quite dead.

Paul_KD7HB:
If lead is poisonous, then vast parts of Illinois, Missouri and other midwest states are uninhabitable. Lead is in all their soil.

The reason metallic lead is not typically a problem in the U.S. is because we also reduced airborne pollution. (Anyone reading this post should consider that the next time they cast a vote from someone who claims the “EPA is out of control”.) When metallic lead is dissolved by acid rain it becomes dangerous to living creatures.

In other words, if you spent less time spouting off and more time reading you would know MarkT’s claim is accurate…

Old lead-rich electronics rotting away in wasteheaps is poisoning water supplies and causing lots of nasty and expensive issues for those that have to deal with the mess.

[quote author=Coding Badly date=1426700942 link=msg=2146129] The reason metallic lead is not typically a problem in the U.S. is because we also reduced airborne pollution. (Anyone reading this post should consider that the next time they cast a vote from someone who claims the "EPA is out of control".) When metallic lead is dissolved by acid rain it becomes dangerous to living creatures.[/quote] Metalic lead is as safe as houses and is what is found in solder. 60/40 solder is perfectly safe and much easier for an amateur project developer or electronics student to work with than the lead-free crap. Soluble lead compounds are a total b*tard and have to be avoided for sure. But 60/40 solder is not that.

I do not have any problem using leadfree solder.

Pelle

It's all a matter of scale.

Lead leaching from waste dumps would come about fourth in the pecking order, after lead mines and processing (Broken Hill, NSW; recent program), lead in paints and leaded petrol.

While it is reasonable (except for the increased failure rate over time, to the extent that this can be determined) for manufacturers to be expected to use lead-free solder, there is no reason why such a constraint should be placed on the electronics repair or speciality markets.

Because - they are such a minuscule part of the industry. Contributors here would be among the very few who might actually repair appliances - or create new ones. :D

If you are buying solder, by all means buy leadl free solder. But I will not be throwing away the roll I am currently using.

Lead free also has a higher melting point.

http://www.kester.com/kester-content/uploads/2013/06/Alloy-Temperature-Chart-15Feb11.pdf

For hobby use, tin/lead solder is fine. For professional use where you use large amounts, lead free is preferred.

Weedpharma

CrossRoads: Yes, no acid core unless you are soldering water pipes together.

Yeah, but you don't want to use 60/40 pb/sn on water pipes...especially for potable lines.

weedpharma: If you are buying solder, by all means buy leadl free solder.

I go out of my way to get the leaded stuff - it flows better, melts at a lower temperature, and makes a nicer joint and is more cooperative w/regards to not bridging pins. I've had consistently negative experiences with unleaded "silver bearing" solder - it's much harder to work with, fights you every step of the way. At least that's been my experience.