I've got an old copper/brass radiator, need to get all the solder off. Thought about making a fire and putting it in. Never done one before. Any tips ? Thanks, John ,,,,
Is this some sort heavy gauge radiator off a large bit of equipment, if it's not it may not be worth bothering about as other items like electric motors yield more copper in a less corroded form. It would be easier to get a reciprocating saw and slice off the core and tank either side of the soldering and then dispose of the soldered part.
I checked the core out, found it had a brass divider between the copper tubes, started to toss it, then thought what the heck, just try an experiment. chopped it up and cast some ingots, Came out looking kinda like polished pewter but still had a slight copper tint. I think the ratio was about 75-80 copper, rest brass. Going to try a pour, see what happens.
Tried a couple pours with the radiator copper/brass blend. Both were really bad, even casting the ingots were crappy. Alloy was about 75-80 copper-20-25 brass. Cleaned the dross each time, same result. Could it be the alloy just isn't suitable for casting? A tips appreciated. Thanks, John ,,,
The ratio of crud to metal would not be favourable: a radiator is designed to maximize surface area and minimize metal used so there's going to be an awful lot of dross to skim. Old taps and plumbing fittings are a good source of brass for casting.
Left pic is the top of the cast piece, right is the bottom as placed in the mold. Both were set in finely sifted material, adobe clay/sand which has proven to be very good for detail. Metal was up to temp. The tip was poured into the vent riser after the sprue was filled. Strange thing is the handle was almost entirely hollow ? This was the third melt of the metal, thoroughly drossed each time. Even used Ole Foundry Man's method of the basin pour with his recommended sprue design. Beats me ,,,,,
Im thinking there’s something about that metal that causes it to not flow well. The hollow handle would likely be solidification shrinkage feeding into the top of the blade. You could try pouring a known casting metal in a mold under the exact conditions to see if you get a better result. Again, my guess is that whatever alloy or mixture you’ve ended up with there just isn’t good for casting. Pete
You're right Pete, metal no bueno for casting. I had to try one more small simple pour just to not let it beat me. Everything correct for pour, same thing, metal froze rapidly before filling cavity. I even added a bit more Cu to see if it would help, that was wasted. Mix wouldn't blend. But I did learn something, heater cores must be full of solder, not just at the top and bottom, there were bumps of gray on surface, solder. Interesting experience but can't say fun, but maybe this might be of help to others who might want to try an old heater core. Oh well, live and never to old to learn. Thanks,, John ,,,