SMD components precisely positioned thanks to stencil printing
For the equipping of printed circuit boards with tiny SMD components, the solder paste must be placed with the highest precision. Stencil printing enables the paste to be applied quickly and reliably, even with a large number of solder points. For SMT prototypes and small batches, LPKF offers the ProtoPrint S family of manual stencil printers that ensure precise results.
The LPKF stencil printers offer exact positioning, SMD fine pitch printing, adjustable print height, speed-controlled separation of stencil and board and a simple clamping of the stencil frames. The PCB to be processed is precisely aligned in the X- and Y-position as well as in the height - thanks to micrometer screws. The mechanical resolution up to a pitch of 0.3 mm (12 mil) enables stencil printing in the ultra-fine range. The thickness of the stencil - between 100 µm and 250 µm - determines the amount of solder paste applied.
The ProtoPrint S operates with stainless steel stencils; the ProtoPrint S RP variant has an integrated ZelFlex clamping frame, which makes the additional use of polyimide film possible. The production of polyimide film stencils can easily be done with the circuit board plotters of the LPKF ProtoMat family. This saves processing time and material costs compared to stainless steel stencils.
For a simple preliminary check of the printing result and for fine adjustment by means of micrometer screw gauges, printing on a test foil can be carried out prior to actual PCB production.
With ProtoPrint it is possible to print on the reverse side of assembled printed circuit boards. The mounting of PCBs on a carriage ensures fast and easy replacement of the PCBs in the small series production.