Good lead free solder availible yet?

Sorry to dredge up this old hot-topic, but I just finished of the last of my 5lb roll of Kester 44 63/37.

Now my son is almost two and seems to be into everything. If lead free solders have finally improved I would like to use them, but if they are still as bad as they were 2 years ago forget it!

I have heard Kester 24-7068-7063 is pretty good, any thoughts?

Also I wouldn't mind trying out the lead-free audiophile stuff either, like Cardas, Mundorf, Johnson IA-423, WBT, Wonder Signature, etc. Which one flows the best?

This is for point to point with proper wiring etiquette, so mechanics of the solder is more important than sonics to me.

Thanks for your help!
 
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Well, I did a little research of a few lead-free solders. Here is what I found:

WBT
Diameter: 0.9mm
Melting Temp: 426°F (219°C)
Silver 3.8%, Copper 0.7%, Tin 95.5%

Cardas Tri - Eutectic
Resin Core
Diameter: 0.8mm
Melting Point: 430°F (221°C)
Silver 4%, Tin, Copper - ratio proprietary

Mundorf Supreme
Diameter: 1.0mm
Melting Point: 554°F (290°C)
Gold 0.1%, Silver 9.5%, Copper 1.8%, Tin 88.6%

Johnson Eutectic IA-423
Rosin Core FLUX RECOMMENDED
Diameter: 0.8mm
Melting Point: 423°F (217°C)
Silver 4.7%, Copper 1.7%, Tin 93.6%

Furutech
Rosin Core (Ersin 362 Flux)
Diameter: 0.7mm
Melting Point 428°F (220℃)
Silver 4%, Tin 96%

Wonder Signature
Rosin Core
Unknown specs

What surprised me is that Johnson IA-423, which has the lowest melt temp also has the worst reputation for good joint wetting. Perhaps the key factor is using a good resin core vs rosin core.
 
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Ex-Moderator R.I.P.
Joined 2005
It may sound strange, but the only lead free I have used made me pretty sick at every solder job
Pretty awful smoke
Im sure its toxic, and maybe even more than lead solder

I have found some cheap lead solder fore heavy jobs
Also bought some SMD solder, which should be very clean, but havent tried it yet
Need to buy some solder with silver

But no doubt, cigarette smoking taste pretty awful after soldering:yuck:
 
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Building a Welborne Terraplane kit 3-4 years ago I had the same experience. I used the included solder. By the time I finished the second monoblock I thought I was going to do the technicolor yawn! I still remember that sickening sweet smell, nothing else is like it.

His current offering

Welborne Labs Solder
Rosin Core (Grade "A" pure natural water white gum rosin) ??
Diameter: 1mm
Melting Temp: 365°F (185°C)
Silver 3%, Tin 97%

Specs look the best. I may order it again! :boggled: Has anyone out there tried it?
 
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Lead free? NO, not yet for me.

I work in the US military/aerospace industry and most of our customers will not accept any equipment built with lead-free solder. We still use 63/37 and RMA flux for everything. All SMT boards use leaded solder. All BGAs have to have leaded balls. We sometimes have to reball lead-free parts to be compliant with the customer wishes.
BTW, I make solid state video recorders for military aircraft and the Shuttle.
 
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Joined 2003
One of my colleagues was doing a COSSH (Control Of Substances Hazardous to Health) assessment recently and discovered that whilst lead is undesirable it's a known hazard whereas the hazards from the weird and wonderful fluxes used in lead-free solder are unknown. Thus, he came to the conclusion that we should continue to use leaded solder because at least we knew what the hazards were (and we could at least make reliable joints).

Personally, I stocked up on "real" solder but I see that it is still available so I'm certainly not going to use this nasty unleaded stuff. My previous house carried the drinking water in via lead pipe...
 
I don't get it. Our current customer (military) prohibits the use of no lead solder. Something about tin whiskers. So, we are using leaded (63/37) for all the SMT and repair work. I can still buy leaded solder here in the US. We have BGA parts with no lead balls reballed with leaded solder balls. Life go on here, with or without the lead. RoHS does not apply to some products as it turns out so you can still buy leaded solder in the US.
 
I tried lead-free solder -- hated it!

Now I use some .5 mm germany-made 60% solder, 38% lead and 2% copper... wonderful. Better than the Cardas quad-eutectic I used before, in that you don't have to clean the flux residuals, which it produces a very little amount of. The Cardas was much dirtier.
 
I thought I'd let my experience be known. I spent 50 bucks on a roll of Kester tin/silver/copper solder and it makes crappy joints at any temperature with the optimum range being very hard to hit too. It eats tips so fast I stuck a 16 penny nail in my old 25 watt Weller and filed it into operation, which is much more compatible with the solder but a little light on the thermal conductivity, especially with only 25 watts to work with. In the end I mostly use the lead free roll to hold the scope cables to the bench, and 60/40 to solder. Very disappointing. I don't even think it is much less toxic on balance. It doesn't stink as much and the buzz is different but still no good.
 
I personally use Cardas Tri-Eutectic now, gives very good soldering results with the Weller. Playing with the temp showed me that unlike seen in Post #2, I need to go for 260 °C for a good melting point. Lower temp doesn't give the flux the opportunity to wet the traces.

It may sound strange, but the only lead free I have used made me pretty sick at every solder job
Pretty awful smoke
Im sure its toxic, and maybe even more than lead solder

Try the Cardas Tri-Eutectic, it ... smells wonders. ;)

I have found some cheap lead solder fore heavy jobs
Also bought some SMD solder, which should be very clean, but havent tried it yet
Need to buy some solder with silver

But no doubt, cigarette smoking taste pretty awful after soldering:yuck:

Sure, That's why I stopped 2,5 years ago :D

Regards,

nAr
 
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SN62 or SN63 Kester "44" rosin is the only way to fly. You should also have a bottle of rosin flux for tough jobs.

Actually if I'm building a board from scratch I like the water washable Kester, "331" I think, but still leaded. If you use a water washable you must wash it within some hours of finishing- the stuff is corrosive and electrically conductive.

We use lead free at work and it's possible to do an OK job with it, but the joints can never look as nice as leaded, plus I'm paranoid about tin whiskers; they're a real issue and can eventually cause failures. IMHO the whole switch to lead free solder was ill considered in terms of total impact and unexpected consequences.
 
Bring back tetramethyl lead. Oil would go to abou $20/bbl

Article in one of the NYTimes this week about the motor-cycle battery industry in China -- seems that an unexpectedly high number of children in the village are suffering from severe developmental disorders. This is one of those issues in which the exercise of some diligence averts disaster, and malfeasance creates a catastrophe.