Using 95/5 Rosin Flux Solder

[ghh3rd]

I have a 5lb spool of 95/5 (Tin/Antimony) rosin core solder. I took 4 feet of it to the Post Office today and weighed it (funny looks from people around me) - 2.1 oz. Now once I figure out how much I need to use, I can just calculate and cut off the appropriate length.

I wonder how much of the weight is from the flux? Anyone else use this stuff? How much did you need to add to get a good alloy?

Thanks - Randy

[454PB]

I've never used flux cored solder, but I doubt the flux would be more than 5% of the weight.

When I add tin, I strive for a total of 2% to 3%. So, add your 4 feet of solder to 4 pounds of pure lead for 3%. Manipulate that ratio to suit other base alloys.

[Gohon]

The Rosin will burn off but will put a lot of gooey black gunk on the side of your pot as well will acid core solder. What I do is use an old small cast iron pot and melt it out by the barn on a propane burner. I stay away from it until there is no more smoke and then I pour it into a Lyman ingot mold up to about a 1/8th inch depth, let it cool, cut the strips in half, weigh and mark each one on a digital scale and throw them in a box. When I need them they are marked and I use how ever much I need to give me a 2% ratio. Since I usually start casting with 8 pounds of WW as a normal working level, that is 2.5 ounces of tin added for me.

[ghh3rd]

Thanks for the suggestion. I think that's a good idea. I have an old small cast iron melting pot that will hold the 5 lbs of solder nicely. Perhaps one of the next weekend evenings I'll stink up the neighborhood and burn off the flux. After the flux is gone, I'll superheat the pot to try to burn off any remaining flux.

I've got some tiny muffin tins that I can fill about 1/8" to make some "solder coins" that I can weigh at the Post Office (some day I need to get a digital scale). I did that with my bars of tin babbit and it worked well for me.

Randy

[randyrat]

You don't have to burn that Flux off.. Just put in some dry sawdust and soak up that Black getto gum scumm, then scoup it out. I found after melting 300 lbs of flux filled solder that is the best way to clean it up.
I even used dried leaves whatever i could find to soak it up, then i bagged it up and placed it in the garbage.
Works like a charm. BTW if you breath a little of the smoke, don't worrie, it won't happen again:shock: Best to wear a mask.
One more tip....It takes less heat to melt ,but longer to cool your ingots.

[lwknight]

Yup, It was nasty. no more for me till there is no other choice.