Solder paste shifted from pad

I have seen this when the fiducials are not spaced far enough in the X and Y.

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Another thing to look out for...

Flex circuits, if not fixtured properly tend to move around and, well, "flex" during screen printing.

At another place I worked, we fixtured the flex circuit on a SMT pallet on the corner tooling pins to "stretch" the flex circuit out, and keep it from moving.

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I don't understand so please explain in more detail. You say ~0.3mm shifted. In what direction is the paste shifted? is it shifted the very same directions on all panels? Only on this product or even with regular pcb:s? What is the size of the panel and how many flex-board on each? You say that you have adjusted the offsets in all directions?? It does not make sense. Unless this is a multi board panel with every second row of board rotated the opposit way from each other, Or.. More details of your product; panel size, stencil thickness, squegee pressure, print speed, solder paste, fiducial location, board location/rotation in the panel. Just give us a brief summary so that we can try to help you out. We have been through a simular issue a long while and ago. But we need more info about your problem. /Sincererly

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Hi Vshan,

If 3 legs are on the pads and 3 legs are off the pads, AND your paste is the same, I'd say your boards are made wrong.

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