I have a brochure warning me never to recycle silicon brass scrap with lead brass scrap. Why?
From:
This site doesn’t mention serious problems except for weakening of metal. I’ve seen other things in the past that mention the danger of lead vapors. Of course these metals, actually bronze in my terminology but often called brass anyway often contain other harmful metals, and in particular zinc in real brass. Take my word for it, no one wants a case of zinc poisoning. But mainly I would assume the resulting alloy with unknown amounts of differing metals has unpredictable characteristics. Copper alloys can be produced with specific characteristics or strength, hardness, malleability, and the tonal qualities needed in bells and other musical instruments but the ratios of metals need to be rather precise. Scrap mixes can be adjusted when the their constituents are known by the addition of other metals such as tin, lead, etc., but the addition of other metals can make it impossible to produce a known result.
If the I can separate them, why can’t the recycler? And conversely, if the recycler can’t differentiate them, how am I supposed to?
It kind of reminds me of the Red Cross’s pre-donation questionnaire about whether you have HIV. Given the consequences, I sincerely hope they’re not relying on a survey to keep their blood supply safe. And given the consequences of mixing recycled brass (whichever those are), I hope they’re not relying on the average Joe to segregate them.
You need to have the certificate of origin to get the best scrap value. Although most scrappers have the laser gun to check metals today.
Dennis
If your shop is milling silicon brass, then you have silicon brass recycling … if your busy enough, you’re hauling the stuff out by the dump truck load … keeping them all separate at the industrial level isn’t that hard …
I run a machine shop, we keep separate bins and barrels for as much as we can.
Off the top of my head I’ll say we last got .88 cents a pound for clean dry aluminum clip. Meaning no cutting oils or chips. About.25 cents a pound for mixed aluminum.
I don’t remember prices from the brass, bronze and copper, but the same idea.
Really? Less than a penny per pound for aluminum, a quarter-penny for mixed? Wouldn’t it be cheaper to send to a landfill?
Most serious recycling facilities and foundry works employ a handheld X-ray fluorescence spectrometer to give them an accurate alloy analysis, not laser beams.
Kind of pricey, so the fly by night scrappers use their eyeballs and experience to determine metal content, usually to the detriment of the seller, in order to lowball the price they offer you. Any certificate of origin they may require is merely an attempt to deter sales of stolen metal, not for the determination of it’s particular alloy. This is not the same as a certificate of analysis, that is typically available only at the original foundry.
$0.88 probably.
nm
I’m pretty sure he meant $.88 which would be a rather good rate for aluminum.
In reality getting anything for scrap is better than paying to have it removed as garbage.
We were at the contract factory in China, and they threw some scrap in the rubbish. We were appalled, and wanted to rescure it.
“Don’t do that” they said. “The people who pay to take our rubbish away will recycle it”
Sorry about the decimal point confusion. I meant 88 cents a pound. It was all a specific grade, unmixed, clean and dry with certification. It was mostly all big clips. Picture a square sheet and cut a circle out of the middle. We used the circles and scrapped the corners. The price fluctuated over the years. The 88 cents was the peak.
I remember a story about a scrapyard, there was a shipping container with all sorts of electric motors. Big ones you could only move with a forklift to tiny ones for say an electric drill. I asked what do they do with them. They ship it to China where the motors were unwound by hand for the copper. Ugh what a job that would be.
Good that you understand that units are important. 
Since my grandfather (ca. 1930) invented motor winding machines that did the whole assembly job without handwork, I imagine a motor UN-winding machine wouldn’t be that difficult to make, 90 years later. G’pa isn’t around to do it, but I’ll bet the Chinese will do just fine.
The one shop I know of that you can still walk into and they’ll rewind a starter motor or alternator for you has unwinding machines.