Some pictures of the matching 2nd upper end part - cleaned, drilled tapped and finished:
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Then onto the next set of parts. Bed cleaned down and a new 10mm plate ready to cut out 4off bracket plates:
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Small pockets cut and holes spotted in all 4 parts:
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First one cut out:
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Last one cut out:
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Opening up the light cnc spots with the same 6mm spot drill:
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First pair of them cleaned up, drilled out, counterbored:
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The counterbore in each part was a bit nerve racking as it is to take an M8 cap head slightly under flush. This means a depth of 8.1mm in a 10mm part, which leaves just 1.9mm left. Although I had my DRO set on the drill press you still drill them blind and need to trust in the gauge not to go all the way through! I guess I could have used the depth stop nuts as a backup.

Second pair straight off the machine ready for drilling:
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