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Kester 60/40 has always been my goto with a 1lb spool lasting a couple of years at least - usually. It's always been just dandy. I just recently ran out and ordered up a spool from a reputable US supplier and lordy, lordy is this stuff crap! I have cheap Chinese silver solder like-stuff that is better. What happened with Kester? Has anyone else noticed this?

If Kester can't be trusted anymore where does one go?

I tried using lead-free solder, both spooled and paste, and find it to be useless. Lead for me.

I can't imagine that lead from old PC boards is a major contributor to lead-related health issues, considering that old paint contained tons of lead, ground to dust or conveniently shaped as chips for babies to munch on.

The real criminals are companies like Apple, who sabotage older devices and make sure their hardware in not serviceable. And to a lesser extent, the sheeple who line up and wait all night to get a new phone every 6 months. Lead is a tiny portion of consumption-driven pollution.

As someone who literally ate paint chips as a kid, I endorse this message.

Lead free solder seems like a clumpy finicky practical joke devised to torment us.

Certainly low quality lead free solder is a waste of time and money. However, I seem to be having issues with regular 60/40 leaded solder. From reputable manufacturers no less. I have a 1/2 pound of crappy 60/40 solder I got from Radio Shack (NexTech - don't know if you had that in the US but it was a late RS brand up here in Canada) that I considered to be emergency supply. It's now better than the Kester series 44. Both are 60% tin, 40% lead. The new spool of Kester just seems to oxidize almost immediately. You can still make a good joint if your technique is good, but unless you clean your tip after every singe joint, regardless of how efficient you are, the iron slags up and becomes useless unless you clean it.

I'm not sure if I'm explaining this correctly, but in the past I could run down the pins on an IC socket (or an IC) and make 5 ~ 6 joints quickly and have each be just so before having to clean the iron tip, then a little wipe on a sponge and a dip into the brass wool and I'd be okay for another 5 ~ 6 joints. With this latest spool of Kester I must clean after every single joint or I get lumps of slag in subsequent joints.

It's really weird.

Could it just be a bad batch? Has anyone else had this happen with Kester or another name brad?

This sounds to me like a change in the composition of the flux, not anything to do with the solder itself.

The following is speculation, but FWIW.... it might help if you're able to reduce the iron temperature slightly. I use a small Weller iron that runs on 12VDC from the wall wart that came with it (and in a pinch I once used it in and on my car!). Anyway, the thing works very nicely in spite of not being temperature regulated.

My only complaint was fouling of the tip, and I cured that by placing a diode or two in series with the 12V supply, thus dropping the voltage (and temperature) slightly.

-- Jeff

Flux makes a lot of difference. Watch how the Northridgefix guy (youtube channel) pours the flux on (he also sells the 'freshest' flux). The channel is actually informative (as he fixes 'unfixeable' Apple machines and saves people thousands of dollars), and amusing.

A temperature-controlled iron is a must (in my experience anyway).

Most people don't realize that it's almost as easy to reflow an entire (smallish) SMT board on a hotplate as to solder in a single SMT resistor with an iron. Solderpaste stencils used to be expensive, but I think it's an extra $20 or so these days. You don't need an expensive frame - just tape it down with masking tape and use a stiff razor blade to wipe paste down. I have a lasercutter, so I cut disposable stencils from sticky paper labels, so it takes me about 30 seconds to drop a label in place and another 30 to paste and peel it off. A few minutes to place the parts (with a magnifier and tweezers), and a couple more to reflow.

Yes, getting good solder just seems problematic lately, as going lead-free (a fad for electronics IMHO) just makes these products worse.

For building audio gear (all vacuum tube) I started using TRT's Wonder Solder decades ago. While they claim it's a proprietary formulation, it's similar to SN62 and still available in leaded in both 0.050 and 0.032 diameters with rosin core. I've gone thru many pounds of the 0.050 stuff over the years and it's always been great. Flows easily and cleanly and perfect solder joints every time.

http://www.trt-wonder.com/page4.html

For my typical PCBs here (6502 related stuff) I started using AIM 60/40 w/3% rosin flux 0.032 diameter about 7 years ago, based on an old friend's recommendation. Like me, he's been soldering for well over 50 years and switched over after not getting great results from Kester, which we all used back in the old days.

I still think a lead based solder is best, but having a silver bearing version is even better. Again, my $0.02, but I've designed and built a lot more analogue audio gear over the decades than digital stuff.

I can normally manage more like 10 to 15 joints before I need to clean the tip (assuming they are all following one another fairly quickly).

I’ve not had any problems with my 60/40 solder, but the last lot I bought was at least a couple of years ago (probably longer) from a U.K. supplier. That was a ‘let’s get some now before it becomes more difficult to find/buy” as I still have plenty of old stock.

Maybe the solder you are having problems with has a different flux?

Mark

I'm a bit surprised at 10-15 joints or fewer before needing to wipe clean the tip. I normally wipe the tip before soldering a component, finish soldering the component and put the iron back to its holder without further cleaning until I'm ready to solder next component. Components can be 40-pin or even 68-pin PLCC socket. I use Kester 44 rosin core 63/37 0.02". My solder iron is temperature controlled Metcal, 700F tip temperature.
Bill

My iron is a temperature controlled Hakko. The solder that I'm using is Kester 60/40 series 44, but it does smell different from the last Kester 60/40 series 44. Of course the last time I smelled the old one it was nearly 3 years old and the new stuff is, well, new. I'm guessing but maybe they have "updated" the 44 series flux? I'll try different temperature ranges. Maybe there is a way to get around this. I normally use 380 F but I see they are recommending 315-375 F. Maybe I just need to cool it. It'll slow me down though!!

My tip is getting funky and requires frequent wiping. I was considering sanding it down.


My soldering iron tip as well. (Rim-shot) I'm here every Sunday. You've been a great audience.