JO HINCHLIFFE (Concretedog) was working on the deployer test rig.

--- quote JO HINCHLIFFE ---

Been working today on a test rig to help determine the rail sizes that will hold the chipstars and that the chipstars will be pushed out of in the deployer. So it started by milling two 2mm wide slots into two pieces of aluminium at the two different depths I was testing, namely 1mm depth and 1.5mm (+-0.02). I then drilled and countersunk the matched pair of railplates and then, using some A+ inspection slip gauges to vary the height and some clamps to keep parallel, test different distances between the plates.

It seems that either depth holds the PCB securely (note this isn't a chipstar PCB just a PCB I had left from another project) and if parallel a gap/tolerance of 0.3mm gives a free slide yet still has plenty of rail wall holding the PC at any given point.

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