Which solder to use? Will 63/37 eutectic work with modern lights?

PB Wilson

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I've had a good deal of soldering experience in the last decade. I've built dozens of guitar effect pedals, a few guitar amplifiers and have modded many guitars and other electronic toys for fun.

I much prefer using 63/37 eutectic solder because it doesn't leave cold solder joints and it flows and hardens in a very predictable way. I've got a few spools of Kester solder in a few different gauges, all rosin core.

With so many companies going to lead-free solder for environmental reasons (which I understand and applaud on a global scale), will my rosin core solder work well when fixing or modding lights? If I'm doing a mod or making a repair, should I remove all of the old solder first or just use them together?

I don't have any practical experience with lead-free solder but figured I oughta figure out how to deal with it since it's here to stay. Any help?

BTW, I have a nice temperature controlled soldering station that has worked very well from delicate work to larger connections requiring a lot of heat.
 

Str8stroke

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63/37 rosin core lead is what I mostly use. I think it is around .22. It is the smaller one. I like the finer stuff. Less mess and seems to fit in tight areas easier. Oh, and seems to melt quicker. Funnier thing is, I never put too much thought into it. I have a small fan to keep the fumes off & out of me. I just clean it all joints when done. Never had a issue. Besides, nothing like a little tree sap in your light. lol I have some of the Silver Bearing stuff from back in my HIFI days. I find it doesn't stick well. Could be my old solder?
 
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Lynx_Arc

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I've had a good deal of soldering experience in the last decade. I've built dozens of guitar effect pedals, a few guitar amplifiers and have modded many guitars and other electronic toys for fun.

I much prefer using 63/37 eutectic solder because it doesn't leave cold solder joints and it flows and hardens in a very predictable way. I've got a few spools of Kester solder in a few different gauges, all rosin core.

With so many companies going to lead-free solder for environmental reasons (which I understand and applaud on a global scale), will my rosin core solder work well when fixing or modding lights? If I'm doing a mod or making a repair, should I remove all of the old solder first or just use them together?

I don't have any practical experience with lead-free solder but figured I oughta figure out how to deal with it since it's here to stay. Any help?

BTW, I have a nice temperature controlled soldering station that has worked very well from delicate work to larger connections requiring a lot of heat.
I've used 60/40 and 50/50 solder by kester and other brands most of my life never bothered with the 63/37 stuff as it was more expensive and I'm still using a roll of solder I got in the 70s as I don't solder much any more. I haven't redone any lead free stuff but this article here talks about it should give you some insight. I'm guessing you can mix lead solder in with lead free stuff but you may want to consider adding a little extra flux in the mix and kind of mix the two solders together a little with your iron on larger joints.
http://www.eevblog.com/forum/beginners/mixing-lead-solder-with-lead-free-solder/
 

PB Wilson

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Thanks for the link. I'm definitely going to keep using my 63/37 solder but I suppose I'll get out the solder sucker and desoldering braid when modding a light. No sense keeping some unknown alloy on the wires and traces when it might cause trouble down the line.
 

Lynx_Arc

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Thanks for the link. I'm definitely going to keep using my 63/37 solder but I suppose I'll get out the solder sucker and desoldering braid when modding a light. No sense keeping some unknown alloy on the wires and traces when it might cause trouble down the line.
You could get some 50/50 solder to use with the non leaded stuff as it has more lead than the 60/40 stuff.
 

Str8stroke

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I also use a wet sponge to help keep the tip clean, along with a few the small tins of tip cleaner. This helps keep the rosin mess down. I should have mentioned that earlier. But when I read you last post, I started thinking others may be new to this and may not use it so often, I forget it may not be so normal for others. I suggest you get two sizes of the suckers. I have a large then a smaller version. I use the spring loaded ones. In a jam, i have used some of those kids ear cleaner bulb things. Oh, a friend of mine uses syringes (minus the needles of course).
Few other random tips:
Safety glasses!!!
Bib
magnify glass or glasses
Helping Hands with the gator clips
I also use Vise Grips to hold parts
Get a scrap 12 X 12" ceramic tile from any flooring store
painters brush
small brass brush
250 sand paper (good for scuffing up battery terminals)

Hope that helps any folks out that may be new at it. I am sure that others even more experienced than me can offer more or better tips.
 

Steve K

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....
With so many companies going to lead-free solder for environmental reasons (which I understand and applaud on a global scale), will my rosin core solder work well when fixing or modding lights? If I'm doing a mod or making a repair, should I remove all of the old solder first or just use them together?
....

quick answer: it's not a problem to use leaded solder when reworking or modifying stuff built with lead-free solder. I've done it for years. No need to remove old solder first.
 

NoNotAgain

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Your 63/37 solder joints will look 10 times better than any tin based replacement solder.
You will need to use a good flux and clean after soldering using IPA.
I use an RMA flux sold by M-Line for soldering strain Gage's due to the nail polish brush for most jobs.

For larger jobs, a flux bottle with needle works well.

I prefer to remove all traces of the old solder for rework.

Google "tin whisker growth" and read the stories about tin based solder. It's not good stuff for micro circuit boards unless the board is cleaned and conformal coated.

I coat 50 or so boards a week with Humiseal due to three year old devices failing in high humidity areas. Now they all get black light inspection and high potting before incorporation into production assemblies.
 
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