Simple Solder Question :P

I watched the Solder 101 video posted a while back and learned a couple new things about soldering.

Now... I am going to use the 63/37 ratio solder for my laser because of lowest melting point it goes the fastest...

I still dont understand one thing

1. What is the difference between the leaded and unleaded solder?
2. Is one better than the other for lasers?

Thanks!

-Brandon

Leaded solder doesn't have ratios. It's basically composed entirely of tin, and maybe a little bit of copper or silver for good measure.

Lead free stuff sucks in comparison to leaded stuff. There really is no inherent health risk with it unless you love chewing on PCB's or eating solder.

Ahh I see was just curios about it!

I just bought a multimeter... Even though the drivers I got from Blord I want to learn how to use a multimeter! It's just one adventure after another on here haha

-Brandon

No that's not correct, the solder blend 63/37 is the tin/lead alloy mix. We use that ratio, rather than something like 60/40, because it is a eutectic mix of the two metals in the alloy. Eutectic solder mixes are special in that they transition directly from sold to liquid phases at a specific temperature point without this intermediate plastic phase that can lead to bad solder joints. You'll also find 60/40 mixes that you shouldn't use for hand soldering. That mix is used because it is cheaper than 63/37, and if you have a very controlled process, such as machine soldering, you can get away with using the cheaper solders.

Le Quack is correct that you should stick with leaded solders if you can. They melt at a lower point (so less heat stress on your components), have better mechanical properties, and are generally cheaper than unleaded solders. It's not like you're going to be creating much waste anyway. Imagine how many lead sinkers already reside at the bottom of your freshwater streams from fishing.

Eutectic is 61.9%. 60/40 is good enough. The "pasty" phase is very narrow and won't change solder performance much.

Bionic-Badger said:

No that's not correct, the solder blend 63/37 is the tin/lead alloy mix. We use that ratio, rather than something like 60/40, because it is a eutectic mix of the two metals in the alloy. Eutectic solder mixes are special in that they transition directly from sold to liquid phases at a specific temperature point without this intermediate plastic phase that can lead to bad solder joints. You'll also find 60/40 mixes that you shouldn't use for hand soldering. That mix is used because it is cheaper than 63/37, and if you have a very controlled process, such as machine soldering, you can get away with using the cheaper solders.

Le Quack is correct that you should stick with leaded solders if you can. They melt at a lower point (so less heat stress on your components), have better mechanical properties, and are generally cheaper than unleaded solders. It's not like you're going to be creating much waste anyway. Imagine how many lead sinkers already reside at the bottom of your freshwater streams from fishing.

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Sorry, I was referring to the unleaded stuff. Looking back I didn't really specify which one I was talking about. xD

I prefer the 63/37 and use it exclusively in the Shop.
And of course it is a small diameter Rosin core type.


Jerry

You can contact us at any time on our Website: J.BAUER Electronics

i bought lead free solder by mistake as it was the biggest roll at the shop...its absolute rubbish, i threw it in the bin.... I love my lead solder

Cyparagon said:

Eutectic is 61.9%. 60/40 is good enough. The "pasty" phase is very narrow and won't change solder performance much.

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There are good reasons the electronic industry adopted eutectic solder, despite the significant increase in cost, over the "standard" 60/40 mix that was in place at the time: the lower melting temperatures and mechanical properties of eutectic solder meant fewer defects and lower mean-times-to-failure--the real source of reduced profits. Industry could only wish that there were an inexpensive equivalent in the lead-free domain.

Eutectic solder should always be preferred by hobbiests for the same reasons, and for laser work it can be even more important. Such soldering is usually done by hand, on movable objects such as diodes and boards held by third hands, often utilizing equipment that is not well-regulated such as soldering irons that are not temperature controlled. A laser hobbiest needs every advantage he/she can get.

Moreover, one shouldn't spoil an expensive broth with one poor ingredient. Is saving a few bucks on cheap solder worth overheating your diode? Cold-joints leading to disconnections? Damaging a diode that cost more than your entire solder spool? Your time and frustration? No I don't think so.

Fun fact: eutectic mix is indeed 61.9/38.1 tin/lead. The 63% comes from the tendency for tin to oxidize and react, so the ratio was kicked up to 63% (cite). That link also contains good information on the consequences of (non) eutectic solder on solder joints.

Use lead solder its much easier to use and melts lower - as Cyparagon (and theory) suggests 60/40 (%tin/lead) is pretty good.

In the industry we are supposed to use lead free solder, its better for the environment and doesn't hurt you if you breathe it's vapors. I can use it now, but I hate it. Lead free stuff is usually tin / silver / copper but melts at a higher temperature and just doesn't seem to "wet" things as well. It reminds me of soldering at too low a temperature with lead solder.

My apprentice tells me lead solder may not be around for much longer, all new commercially made products here and in EU (not sure about the US) are not allowed to use leaded solder any more.

Will be stocking up on a heap of 1kg rolls from Jaycar if that ever happens!

Things said:

Will be stocking up on a heap of 1kg rolls from Jaycar if that ever happens!

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When I first heard about it I was in Townsville and I we cleaned Jaycar out of kg rolls!

That was 4 years ago and you can still get it, so I'm ever hopeful!

I really pity the folks in the EU that are forced to use lead-free solder even at the hobbiest level. If they ever decide to ban leaded solder for all uses here I'll definitely buy a crate of it to last me until I die or see what I can get from Chinese manufacturers (though I really prefer quality brands like Kester). I just hope this lead-free stuff only remains a thing of industry and they don't seek to apply a blanket law that encompasses hand-soldering.

I am certain if EU ban the lead-solder it can be bought from outside EU. The world is bigger than EU.

dam, I'v been using lead free solder (rosin core) in my builds. It worked fine, although tinning the soldering iron is impossible as the solder just gathers in a blob and drop off, and doesnt stick to the tip at all. would leaded solder work any better?

Sounds like your tip might need cleaning or replacement.