Lead free solder

[Tn Jim]

I was gifted a full 1lb roll of solder over the weekend. The box says "Sterling premium quality lead free solid wire solder". Backside of the box says "contains tin, copper and selenium", but it doesn't give a percentage of anything. My question is can I cut a 3-4 inch piece of this and add it to my COWW to up the tin percentage without contaminating my alloy? I'm not even sure what selenium is.

[Winger Ed.]

You have about a 99.99% chance its the new generation Lead free '95/5' plumbing solder.

I'm as un-scientific and low tech as it gets and I use it like I would regular pure Tin.
For the last 40-ish years, its always done a good job for me.

[imashooter2]

5% of 2% is 0.1% of the total mass. Your COWW probably have more “contaminants” than that to start with. Use the solder with confidence.

[JonB_in_Glencoe]

Google the part number to get the solder makeup.

Bottom line:
4" of wire solder ain't gonna do jack to a pot of boolit alloy.

[Rickf1985]

Have you downloaded the alloy calculator from the site here? It will make a lot more sense of what you are trying to do with your alloys. AND save you a lot of work and waste of good lead.

https://castboolits.gunloads.com/showthread.php?105952-Lead-alloy-calculators

[lightman]

I'm guessing that your title, lead free solder, is correct. If so its 95% tin and the small amount of other stuff won't matter for the purpose that we use it for. Nice freebe gift!

[NyFirefighter357]

That is one of a few modern lead free solders. That one they replaced the antimony with 4-5% copper it has 91% tin with other trace metals. It's also $35lb.

[winelover]

I mix one full roll of 95/5 with twenty pounds of pure to get 20-1 bullet alloy. Close enough for my use.

Winelover.

[bangerjim]

It's gonna take at least 1\2 of that roll to do anything to help a 20# casting pot mix. You can make a few good boolits with it. That's all. A 4" piece will do nothing for you.

I would keep it around for doing sweat copper joints around the house and not waste it in a casting pot.

Buy your PURE Sn on here or RotoMetals in quantities that actually mean something.


banger

[MattOrgan]

I pretty much use an alloy of about 20:1 for everything. I’ve been using scrap lead for 50 years. A free pound of lead free solder makes 20 pounds of pure lead more or less 20:1. Not insignificant. I generally add solder to unknown lead alloy until the surface tension looks right and the molds easily fill out. Solder is frequently very cheap at garage sales and thrift stores, each time I think I’ll use my last solder I’ll run across another pound or two. My favorite solder is rosin core. Doesn’t take much to flux your pot.