The AM Forum

Has anyone worked with the new, lead free, "environmentally
friendly" solders?

I understand that the new stuff uses antimony, copper, tin,
silver and is attempting to replace the lead by using a majority
of 96% tin in the mix.

I read it does not have the shine of lead based solder, but melts
close to the same 161 degrees F.    It is mandatory to use Zircon
encrusted tweezers to hold it.

Before I stock up at Radio Shark with the old Kester Sn60/Pb40
mix, is the new stuff just as good?

T

Zircon encrusted tweezers are only for dental floss tycoons.

I used some for plumbing back in the late 80's. It works but didn't look right when cooled or seem to flow as well.

I'm probably fixed for life with 40/60 stuff.  A friend who was moving out after a divorce gave me a couple of unused 5 lb. rolls of small and large diameter.  That was in 1981.  I haven't even used half of any of those rolls, and have done hell of a lot of soldering over the past quarter century. In the meantime,  I have picked up one or two more full 5 lb rolls at hamfests.

Rolls of lead solder is something I always keep an eye out for at hamfests and flea markets.  If it is still on rusty metal reels, it is sometimes tossed in the bargain boxes under the tables as junk.  However, I suspect now that the lead issue has come into public awareness, along with the implication that 40/60 (or is it 60/40?) is about to be taken off the market,  it won't be long before real lead solder will become like power triodes - very expensive and almost impossible to find.

Let's hope someone doesn't plant the notion in the audiophool community that amplifiers with lead soldering sound better.

If that happens, I hope they are told to use acid core!

Just me and the pygmy pony over by the dental floss bush......

Don - That could NEVER happen. After all, real audiophools will only use Western Electric hookup wire and Western Electric branded solder - hi!

Tom,
I've used the lead free stuff on electronics.  It seems to flow OK but it's not quite the same as 60/40.  I think even the flux is different because of the composition of the solder and that maybe a reason for the slight difference in flow characteristic in addition to the composition.  As far as the look of the new solder, I agree it does look different when solidified compared to tin/lead.  

I do wonder about its electrical characteristics though.  I haven't heard anything regarding this though. Maybe it's nothing to worry about since there's an abundance of silver.  This solder will probably be more expensive because of the silver.  Don't want to think about that.  But to answer your question directly, it's slightly different but noticeable. I'm sure after getting used to it you probably won't notice the differences.  Of course, that's me talking and I still prefer to use 60/40 and I have several types of solder.

I too have a pretty good collection of tin/lead (60/40). A relative of mine works for an electronics distributor and every once in a while he floats me scraps of stuff they "sweep up" to haul off to the trash can.  For some reason that stuff makes it to a box and it arrives on my door step.  My last shipment contained 7 or 8 one pound rolls of solder of different brands, sizes, compositions including lead free.  I figure I have about 30 lbs of solder from my cousin. Enough for a lifetime of soldering.

Does anyone know for sure if solder will give you lead poisioning if exposed to it for a longtime especially if you handle and solder alot?
I've had my blood tested in the past and tested negative for lead even after all the years of handling the solder and drinking tap water from plumbing soldered with the old stuff.  One has to wonder.

 I don't know. It may be offset by the cost of disposal of the 60/40 stuff. The way these 'Green Weenies' work, you can bet to get rid of anything with lead in it will be tantamount to a king's ransom. Hell look how difficult it is to get rid of a refrigerator or air conditioner. The reason you are getting rid of it is because the freon is already gone!
Sorry, just musing.

I dunno...

If we were meant to use non-lead solder, why did the Almighty invent lead ???



73, keep smiling...

Mike
KM1R

I second Tom's observvations. I have seen some drop-dead gorgeous soldering on plumbing done with the new solder, but it's not the same to work with. It's more difficult to use. Doesn't seem to adhere to the work as easily. It seems to work the best with the acid type of flux and only fair with standard rosin flux. It's good for plumbing, only 'fair' on electronics, IMO.

I'd do a mail order of *real* solder from Newark or Allied, IIRC someone still  sells the top-quality 60-40 Ersin multicore stuff. My fave is the GC electronics solder containing 2% silver. Hard to make a bad looking connection with it and the silver content keeps silver plated components and wires from leaching. Check Ebay, too.

For plumbing, the best stuff is silver brazing sticks.  They come in about 18" lengths, a flat rod about 1/8" wide.  You need a good brazing torch; I use Mapp gas.  A regular propane torch won't get hot enough to melt the solder.  The copper needs to be heated to a dull red.  Just be careful not to overdo it; I have been known to end up melting the copper!.

Once it comes to temperature, copper sucks the stuff up like a sponge soaks up water.  No flux is needed.  The only cleaning you need to do is brush away any surface crud or scaling oxide.  The copper does not have to be polished to a shine to take the solder.

That is the only thing I use to braze ground system components together.  My 160m vertical ground radials were brazed to the copper ribbon at the base of the tower nearly 25 years ago, and still no sign of deterioration whatever.  The solder joints just developed a stable black patina that hasn't changed for years.

I once soldered radials to a bus wire in an earlier vertical using lead/tin acid-core solder, and I had to redo the job about once a month.  The chemicals in the soil turned the solder into white powder and after 2-3 weeks, the radial wire would simply fall away from the bus wire.

A plumber told me that it is now illegal to do plumbing with lead solder because the solder does exactly the same thing when it reacts with water in the pipes, and the lead leaches out into the water.

I have  heard a theory that the Roman Empire fell because the population was poisoned with lead from the solid lead pipes they used in their plumbing.  Lead poisoning causes brain damage to children and is known to substantially reduce their scores on IQ tests.

The word "plumbing" comes from the Latin word for "lead."  The modern French word for lead is "plomb," and the word for plumber is "plombier."

Just look around at the next hamfest you're at!

Seriously though, does anyone have experience with using lead free solder for repairs on old joints made with  60/40 ? This what concerns me the most .

                                                               Ian VK3KRI

http://www.hamsexy.com/cms/index.php

Tom vu,
I will be running a lead free soldering course next weekend at the new qth.
Stop down if you want to learn how to make big bucks as a plumber.
I hear map gas works best as the melting temperature is higher.
It is a bit harder to work with. gfz

Mental Toss

Miscellaneous observations:
THe entire push for lead-free electronics is due to the concern with ground-water contamination from discarded electronics in landfills.  If you look at where the output of lead mines goes, 3% of lead consumption goes to solder, 70% goes to lead-acid batteries.  Do the math.

I work in the auto industry which is going lead-free in a big way.  The so-called silver solder which is mostly tin is OK, but solidifies with a satiny sheen that makes it look like a cold joint.

What I have a real problem with is the new solders with 'organic' fluxes in them, as opposed to good ol' rosin core.  The organic flux is hygroscopic, and if there is flux contamination between two IC pins, that means there is about 1M of leakage resistance from that.  You have to scrub the boards with ethanol and water to remove it, which makes the ethanol useless for human consumtion afterwards.

I'm up to my ears in this at work...it's a huge issue in industry and we're (you're ) going to spend many millions of dollars for this change....even though:

In the US, 80% of the demand for "new" lead in products is met by recycling.

Stuff that's designed to last 20 years or more (industrial electronics) is being treated the same as the throw away cellphone or PDA

There's no agreement on which alloy is the best replacement

There's little field history or industry experience with any of the replacements

There's no data showing lead actually does leach from metallic form into groundwater..

Are we having fun yet?

John K5MO

Just spent 3 days getting use to lead free solder. First suggestion get a map gas benzo matic. I bought one with instant on button that works great. No striker or playing with matches. Just push the button and
you have a perfect flame. No wasted gas. perfect for tower work.
The trick is to not over heat and get used to the dull color.

Tried it here, various mixes with so so results. I suggest you stock up on Kester Sn63/Pb37 while you can still get it.

For plumbing try the tinning flux. It works much better than the plain organics and helps to unify the flow.
When I re-plumbed the house (2 1/2 baths and the kitchen) I didn't use it till I was more than half done. What a diff.  :)

We've been using lead free here at work for more than a year. The learning curve is painful. 1st run pass rates are just now getting to where they should be. Major problems have been bad joints due to lack of flow and board contamination when the super secret formula flux didn't fully wash off.

Hi Don,

I have a question regarding the MAPP gas. I need to braze part of an old metal cabinet together and I tried using a propane torch + silver braze but I quickly discovered the propane wasn't  hot enough. I am thinking of trying the MAPP gas . Just  a couple question ? Does the MAPP gas burn in the same torch used for propane ? Or do I need to buy a special torch outfit for use with the MAPP gas ? Also, does the MAPP gas require an oxygen supply ?  

Thanks,

John H. (N2IZE)

Hi John,

The MAPP gas can be used in the same torch. Just look for the YELLOW bottle. I have a self igniter that works with both !

mine also does both types of gas but my old one does not.
MAP burns pretty hot but not sure if it will flow braze rod.

Yes it will braze on limited size items. I've done some small repairs on the tractors with it. My usual approach is:

There's only one way to find out !!!!   :p

I bought a kit with my first tank of Mapp gas when I put up my vertical tower and radial ground system. I still have and use it after 25 years, on my 2nd or 3rd bottle of gas.  The torch assembly came with the bottle in the kit.  Not sure if it's exactly the same as the one used for propane.

Some gases require different size orifices in the nozzle.  A local church had a new propane furnace installed.  It wouldn't heat the building above 60 deg. F.  After two years of dealing with the jackleg who installed the system for a "discount" price and hadn't a clue what was wrong with it, they called in a professional HVAC specialist.  He immediately discovered that the furnace had natural gas nozzles instead of the type required for propane!  He changed the piece, and now they have all the heat they can use.