1. Realizing not all PCBs will be warped, but for those that are, the tooling can be set when the board is in contact with the stencil, which will take out some warp. On an MPM, the vacuum box helps to hold the board flat
If the warp is more severe, or on placement machines, a setting plate can be used. If you have board sag, the pnuematic setup force can be increased to put more force on the board once the pins come in contact with it.
How do you currently handle warp, and how much do you see?
2. The compliance of the cap would take care of small components that would be likely to skew in such a manner as you described. The cap is compliant on its edges, with a diameter of .250". The pin is 0.125", giving a 'doughnut' of 0.0625" If the component had a low enough height, no defects would be seen, as it would 'sink' into the edge of the cap. If the height of the component is likely to be a concern, the pin could be lowered away to prevent further defects.
Grid-lok pins are independently, mechanically locked in place. They do not move once locked, unless lowered by purpose, which they can be.
Pins would become stuck if mechanically damaged or material was forced into the bore. We do not see pins sticking in normal production currently. We offer a warranty and service agreement on module performance.
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