It's the first stage, we have a stencil printer which applies the paste to the board. The shim is made of steel and is etched by laser to expose where the paste needs to be applied.

You just the panel into the stencil printer and then it uses a metal squeegee to apply the paste to the panel.

However, the people who make our pick and place machine have a jet printer which can apply the paste, think of it as a big bubble jet printer that dispenses paste instead of ink.

Video below that I took of it in operation at their UK office!



Again, this machine uses linear motors and it moves incredibly quickly. The forces involved are so high, that the actual black "casting" you can see inside is a granite that has been ground to a powder and then formed into a shape with a resin, it weighs several tonnes!

Obviously screen printing is always going to be quicker, but the advantage of this machine is that you don't require stencils to be made (they're about £100-£200 each) and it can vary the amount of paste to be dispensed on a pad by pad basis - you can also avoid putting paste down where you don't need it (in the case of build variants etc) which you can't do with a shim.

Oh, it also costs a cool £100,000!