PCB contents - weights

[g_axelsson]

I don't even mess with the slots, for one they are flash plated at the tips only usually and another thing they use barillium (spelling?) copper material as the base metal to get that spring action to make good contact with the fingers. which is nasty to dissolve, nasty chemicals.

The slot connectors are not made with beryllium copper. They are often made of phosphor bronze wich contains a small bit of tin. Dissolving the metal in nitric acid creates the hated metastannic acid that is almost impossible to filter.
I usually only process these slot contacts when I'm low on better scrap (not likely to ever happen) or when it's older and more heavily plated slots. (I have a couple of boxes stashed away with 386 mother boards.)

The black slots that Patnor marked in red are ISA slots and it was hard to find new computers with them ten years ago. Today they are virtually extinct.

The most common place to find beryllium copper in is CPU sockets.

Göran

 

[lysdexic]

I don't even mess with the slots, for one they are flash plated at the tips only usually and another thing they use barillium (spelling?) copper material as the base metal to get that spring action to make good contact with the fingers. which is nasty to dissolve, nasty chemicals. I take the IDE male pins only off MB's and toss the rest. just my two cents on that.

even the IDE male pins are not all that great for gold, need a lot of them to yield a return, they go in the sulfuric cell.

As always the answers to things like beryllium copper are already here somewhere once I know what to look for.

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=47&t=5145#p44161

More insight gained and lessons learned but that belongs on a depopulating boards thread. I didn't mean to hijack patnor's thread.

Thanks everyone.

-Doug

 

[gaurav_347]

can anyone tell me what is the average weight of one bga chip ?

 

[Barren Realms 007]

can anyone tell me what is the average weight of one bga chip ?

There are really too many types and sizes to answer that.

 

[solar_plasma]

If you mean the bigger ones like north- and south bridges, they are between 2 and 4,5 g.

 

[gaurav_347]

Thank you!