With the low grade boards, just like others have said, take off anything that pays more than $.15-$.17/lb. I get aluminum heat sinks (leave the steel ones on), flyback transformers separate and go with motors/transformers (pop the underside of the board a couple times with the "peen" side of a ballpeen hammer and they usually bust loose) and any wires go into the insulated wire bin. My yard calls low grade boards "breakage" so it doesn't matter if they're broken!
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I also toss in cut-off plugs and connectors from electrical cords in with the same stuff. If I was doing hundreds of pounds of these a month I probably wouldn't bother, but at the low volumes I process it makes sense.
Most of my low grade stuff comes out of TV sets. A lot of guys don't seem to think TVs are worth the effort, but I've gotten pretty good at getting them apart and the materials sorted in a reasonable amount of time. I leave the CRT in the case with its steel frame and then put the back cover back on. Then the rest goes out into the trash; our local trash company picks 'em up without complaint. I picked up 2 monitors and three TV sets just yesterday, so they are still plentiful, although I wonder how long that will last with everyone going to flat screens.
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