HP Etch produces stencils in thicknesses from 0.030 mm up to 0.350 mm.
In order to make apertures with straight walls (without the ‘hourglass’ shape), HP Etch uses specially built etching machines with a high number of etch nozzles positioned close to the metal, with individual pressure and flow control on both the top and the bottom side. There is also constant regeneration of the etching fluid, which guarantees high precision etching over time.
As well as advanced equipment and precise process control, producing high-quality stencils that meet the market’s demands also calls for in-depth knowledge of etch compensation.
High-precision etching makes it possible to determine the stencil wall angle with great accuracy. A cross-section of HP Etch’s stencils shows that the aperture is trapetsoidal shaped to improve paste release properties (see figure).
As long ago as 2005, HP Etch switched from standard steel with a grain size of 20-30 μm, to a steel with a finer grain size of just 1-2 μm. The finer grain size makes the stencil walls even smoother, resulting in better paste release.
All of HP Etch’s stencils are now made from this fine-grain material.