Effective stencil production through homogeneous tension

Paul Boughton

High precision is a critical factor for laser cutting of SMT stencils. With LPKF’s new stretching frame for stencil foils, a continuous tension with a homogeneous tensioning force distribution is achieved.

A single tensioning system suffices for the entire range of standard stencil sizes. The variable frame guarantees fast changeover from one size to another and slashes setup times.

The LPKF stretching frame was designed for fast and easy use in production. A newly designed clamping mechanism ensures even clamping of the foil to ensure a high cut quality.

In three steps, the operator receives a perfectly tensioned solder paste stencil: With the length adjustment lock released, the stretching frame is roughly set to the length of the stencil. The lock is then engaged and the stencil inserted as a frameless foil. After that, the hold-down device is closed and a uniform clamping force created over the entire foil width by compressed air.

For the cutting process, uniform foil tensioning is necessary. This is achieved with an adjustment knob that also serves as a tensioning force indicator. This allows the optimal tensioning force to be applied for every material.

Florian Roick, Strategic Product Manager for LPKF’s stencil systems, says: “The new stretching frame can be used for foils with lengths of 400mm to 850 mm and widths up to 650 mm. It lowers setup times and makes foil cutting easier. A setup time of about a minute can be achieved in practice.”

The stretching frame can be loaded into the LPKF StencilLaser in normal or flipped orientation to enable machining of both sides of the stencil.

For more information, visit www.lpkf.de