What common scrap copper usually contains Beryllium? Or can I tell via some test if the copper has Beryllium?
I’m not aware of simple tests for Beryllium. Also, other ingredients for Cu alloys can make them fairly hard… not something one would probably want, especially when starting out.
Two types of commercial Cu that are known to be safe - and machine well - are “101 copper” and “110 copper”. Both are 99.9% pure Cu - what’s not Cu is known to be safe. There are other safe alloys but they get pretty hard.
The “101 copper” is the “oxygen free” Cu often associated with expensive audio cables.
If you choose “110 copper” I would recommend “060” or “H02”. Stay away from “H04” (full hard temper) until you’ve mastered something softer.
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