Best Lead-Free Solder Out There?

[TimLaw]

Hey

In general, is there any particular brand or formula of solder that you have found to be the best in your soldering experiences? We usually just use your basic rosin core solder from Radio Shack or whatever is cheapest, but I was wondering if there was anything better. (That stuff smells absolutely horrible!)

Any suggestions? What ratio of material. x% of tin, x% of ....

Price is not an issue. We sell high quality stuff and we don't sacrifice at all.

We have to use Pb-free or else some sort of environmentalist will jump us, regardless of how dangerous or not dangerous it is. (I don't believe in it.)

Thanks.

 

[BrownOut]

I use RS solder with no issue.

 

[kiriakos-gr]

I got for an project of my ANTEX solder with Silver , and it was very hard to use ..
Problems at melting properly , and no shinny finish.
At list it did a good job as ( Low Oms solder )

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[Warpspeed]

I worked for a company that imports pallet loads of really nasty lead free solder from China.

We also did warranty repairs on Chinese electronic equipment, and the same horrible ultra cheap lead free solder was all we were given to use.

It was so awful, we smuggled in our own 60/40 leaded solder from home, out of our own pay................... It was that bad.

Asking what is the best kind of lead free solder, is rather like asking what is the best type of really good sex you can have all by yourself.

NOTHING beats real solder.
And real solder has lead in it.

 

[Reloadron]

Since we don't know your specific application and use it might be wise to just get familiar with what is out there in the Pb free solder family. This link should get you going with information.

Ron

 

[TimLaw]

I agree. The lead-free solder really doesn't come close to lead solder. We always used leaded but in the last stretch of time, we've kind of been pushed to use lead-free and I am really afraid of using it. Something is going to go wrong with it.

sigh...thanks for the link to kester. I'll check it out and see if we need to make any changes.

 

[Sceadwian]

The joints of lead free solder are more brittle than leaded solders, I wish I could remember the formulation but there are some lead free solders out there that have nearly identical melting temperatures to leaded but I doubt they flow as well as leaded solders, lead is used in solders for a very good reason and there will never be as replacement for it that is as good. That being said all major board makers are probably going to end up switching to it. The joints should be just about as good as leaded solder as long as care and attention is given during soldering, board cleaning and an appropriate flux should be given some serious consideration.

 

[colin55]

The problem is this: Lead free solder joints fracture much easier and for no apparent reason, than leaded joints. You will find that all lead-free equipment will suffer stress fractures in years to come. This has already been proven with accelerated testing. We are going to have enormous problems in the future.

 

[Sceadwian]

Colin, the reason is readily apparent.. it's because the solder doesn't contain lead... Lead is a very ductile metal that flows well at a low temperatures, and is easily mixed with tin that's the entire reason it's used in solders in the first place. Although some lead free solders have issues with spontaneous tin whisker growth I don't see this as being any huge problem as they'll develop lead free solders and pre-cleaning or design changes that will compensate for the lack of lead.

Personally I think it's all blown out of proportion though, lead isn't THAT much of an electronics device, the chips themselves contain nasty metals and the epoxy boards themselves are the bulk of the product, not to mention the copper traces themselves, plastics and various other compounds (dissolved copper is particularly bad for plant life) The problem isn't that lead is used, it's that electronic devices aren't properly recycled and are landfilled commonly, if proper recycling facilities existed and it were common for devices to be recycled there wouldn't be a problem in the first place.

 

[colin55]

The point I am making is this: Lead-free solder is so critical that some products fail after a few years due to the combination of the solder, the surrounding metals, the heat generated, vibration, and any slight impurities present in the manufacturing process. I have seen whole batches of boards fail after a few years due to cleaning that was not absolutely 100% perfect.
That's why there are so many different combinations of lead-free solder on the market. Lead-free solder simply does not work. Even the best lead-free products are just holding on. Whenever there is stress, vibration, temperature-rise - they fail.
This was obviously introduced by a non-technical non-electronics, person.
CFL's are going to take over as the next generation of pollutants – and it’s going to be much worse.

 

[Sceadwian]

some products have failed after a few years. Cleaning, the environment, heat, vibration, those are all important things to know about when you're soldering in the first place, they just can't be swept under the rug like they used to be because there's no lead to act as a backup of poor practice. Even lead solder fails if you screw it up bad enough, non leaded solders just aren't as tolerant.

The reason there are so many formulations is because everyone is looking for the best one, without the lead all the other variables become hyper important. CFL adoptions rates aren't enough to worry about for at least a half dozen years, until then their are entire industries hell bent on finding something better.

 

[TimLaw]

Anyone have any opinions on Kester 275?

 

[Sceadwian]

You're not going to ever find a straight up replacement with the same results, you have to look at your prep and cleanup procedures.
I Googled a little.

The chemistry is based on some of the
same principles that have been safely used for
years in mildly activated rosin fluxes.

There is no qualification here that says it's as good, they go out of their way to avoid saying it.

As long as your boards/environment are already clean at the start you might not need to add a pre-clean, but to get the same results with the solder compared to a lead based one you'll have to re-evaluate cleanup as you'll need a more aggressive flux to compensate, or you may need to pre-flux the boards. If you use a more aggressive flux and do a wash afterwards or apply the flux separately from the solder wire itself you'll have far fewer problems than if you try to simply find a drop in replacement, there can never be one as the way lead based solders react is because of their lead content, you can't just ignore that.

 

[TimLaw]

I guess what is being said is that you can find a good replacement but there is really no telling. And it seems that good lead-free is going to be much more expensive than a =/= lead solder.