Laser Cut Adhesive Stencils

Laser Cut Adhesive Stencils Description:

Laser cut stainless steel Adhesive Stencil for adhesive printing.

Adhesive stencils are used to solder SMD components with a solder wave, whereas the components are fixed with an adhesive. The adhesive spots are print in one printing process by using a lasercut stainless steel SMD - stencil and the components are placed and soldered afterwards. Stencils with a thickness of 150-400µm are used preferable. The diameter, height and number of the adhesive spot is determined by the component geometry, the data are prepared from the pick and place process or from an in-house library. The Adhesive Stencil replaces the expensive and time- consuming dispensing process.

Benefits:

• Exact adhesive spot height
• All adhesive spots in one printing process
• Cost-effective alternative to the dispensing process

Combination adhesive-/paste printing

If it is not possible to solder all components with the solder wave, a combination of paste- and Adhesive- Stencil is used and a so called „wet“ in „wet“ printing step is carried out. In the first step the solder paste is applied for the reflow process by using a lasercut SMD – stencil. In the second step the Adhesive Stencil is used to print the adhesive for the solder wave process. To avoid a smearing of solder paste deposits during the adhesive print process a recess from the bottom side of the Adhesive Stencil is performed in height and form of the paste deposits and sealed with an adjustable cover. The size, height and form of the cover are individual adjusted on the layout of the printed circuit board.

Solder paste- and Adhesive

If the areas of paste- and adhesive printing are separated distinctly in squeegee direction, the solder paste and adhesive is applied within one printing process. Separator plates are welded in on the squeegee side of the SMD - stencil to avoid a mix-up of solder paste and adhesive. The squeegee blade has to be adjusted to the separator plates in the form of slots in the squeegee blade.