Acid core solder?

[sasquatch76]

I found a few rolls of 50/50 Sn/Pb solder. But it's acid core. Do I need to smelt this and flux off the acid before I use it? I imagine fluxing it with pine savings would do, but will this get rid of and neutralize the acid?

[JSnover]

I don't know if pine would do it, but you are right; get the acid out.

[bangerjim]

Be VERY careful with that stuff! The acid core is very corrosive. They used several different acid formulas in that type of solder.

Best way to melt it down is to feed it gradually into the pot with about an inch of molten starter lead on the bottom. If you throw the whole roll in, you will the cousin.....ACID TINSLE FAIRY........showing up. Use short lengths of about 18" and watch the end in your hand......acid could/will come out!!!!!!! It is normally a gel but will run and flow.

ALWAYS wear a FULL face mask!!!!! And make sure there is a good breeze blowing away from you. Be prepared to get acid on the gloves you are using, so use some old ones you do not care about.

Not good stuff, but if you are careful, you can salvage it.

Once you get it all melted, flux it normally with saw dust 3x.

good luck!

banger

[sasquatch76]

Thanks. Sounds like a plan. I'll be geared up with all my safety equipment and I'm using an old stainless steel pot I don't care about. I cast/smelt outside so plenty of ventilation. What if I water drop the ingots into baking soda/water mix, would this help to get rid of the acid?

[JSnover]

...water drop the ingots into baking soda/water mix, would this help to get rid of the acid?

Only on the surface. By the time you have fluxed, skimmed, stirred, etc, I would think the ingots are clean enough.

[KYCaster]

The acid IS a flux, a very good flux; that's why they put it in there.

Expect some boiling and sputtering, but I've never experienced a steam explosion from acid core solder. Err on the safe side, though and use Banger's advice.

The acid fumes are nasty stuff and can cause severe respiratory distress. A good exhaust hood and appropriate respiratory mask are essential.

Use saw dust to absorb the excess acid not consumed in fluxing. Double bag it before disposal to avoid any contamination.

Jerry

[sasquatch76]

I'm going to be very careful and add it a piece at a time. I'll be outside and wearing a breathing mask, old welders gloves, face shield, and shop apron. I should be good to go. I don't expect any trouble, but I'll be ready for it.

[zuke]

I've tossed it into a pot of WW during a big melt.With all the rest of the **** smoking up, I just sat on a chair up wind.

[bangerjim]

Thanks. Sounds like a plan. I'll be geared up with all my safety equipment and I'm using an old stainless steel pot I don't care about. I cast/smelt outside so plenty of ventilation. What if I water drop the ingots into baking soda/water mix, would this help to get rid of the acid?

As said, the acidic content will be LONG gone by the time you get that solder to pouring temps!!! Don't worry about the soda and water. (Mabe some scotch & soda?!?!?!?!?)

The stuff in there could various forms of acids or zinc chloride. All have been used in the past.

As far as "I did it with no problems"......99 times you could be OK. It only takes that ONE time to be sorry! Please.....err on the side of caution! The way I described it is the way I do it.

We do not want to hear about another Phantom of the Opera complexion!

banger

[62chevy]

I put 50/50 solder is my pot of pipe lead even read the label to see if it had any flux in it but it didn't say so added it to the pot and the solder melted and the flux bubbled. It does smell so stay up wind of it. It was an old roll of Radio Shack solder I had bought over 30 years ago and had a price of $2.89 on it. :veryconfu

[sasquatch76]

Got it smelted today. I did have some black goo on top but it didn't explode or anything, just smoked. The 3 fluxes with pine shavings took care of most of it, I then hit it with some wax flux before I poured it. Came out clean and nice.

[bangerjim]

Excellent! Some of that old solder will have the liquid core dried out. I 3 rolls of it that way and one roll that is still a gel which I still use for different sheet metals.

banger

[jakec]

Excellent! Some of that old solder will have the liquid core dried out. I 3 rolls of it that way and one roll that is still a gel which I still use for different sheet metals.

banger
that explains why my rolls are all just hollow. ive got about 15 6 lb rools but theyre all older than me and im 35.

[bangerjim]

that explains why my rolls are all just hollow. ive got about 15 6 lb rools but theyre all older than me and im 35.

Deep inside the rolls there may still be some moisture, but the chemicals are all still there. The anhydrous portion of the flux had evaporated.

banger

[jakec]

Deep inside the rolls there may still be some moisture, but the chemicals are all still there. The anhydrous portion of the flux had evaporated.

banger

makes sense. i just clip off little pieces and lay them on top of the melt and they kinda smoke a little as they melt in. theres usually a small amount of black gooey stuff too that must be those chemicals. it does a good job of fluxing though.

[GaryN]

I wouldn't do it in the house or any other enclosed area. I would do it outside and stand upwind of it. It has some nasty stuff coming out of it. I would buy it again if the price was right.

[lwknight]

Most acid core is zinc-cloride. The wood shavings should absorb most of it. If you burn off the shavings trying to flux the already fluxed by acid you will probably just bond the trace zinc in your alloy.

Best way I found is to melt it in a sacrificial cheap pan or whatever and let it cool. Then dump the ingot out and wash off the acid with hot soapy water. If it actually hardens then chip it off with a small hammer and scotch-bright.

[odinohi]

I think I may have put some acid core solder in my promelt. Been fighting drips ever since. Called RCBS and they are sending me a new pot,spout,and new rod free of charge. Been fighting these drips for too long know. Great customer service rcbs is.

[shadowcaster]

I smelt down acid core all by itself. I put some shavings in the bottom an old solder only pot, lay in all the solder, another pinch or 2 of shavings on top, put the heat to it, step back, and let'r burn. After it all melts/burns, stir it good, flux again and pour your now clean solder ingots.

Shad