Draft Angles - In order to assist with part release adequate draft angles are required for both exterior (plastic is shrinking away from) and interior (plastic is shrinking onto) sidewalls. The minimum draft angle required for exterior sidewalls is 1 ½ degrees per .001” of texture depth. Interior sidewalls require a minimum of double the draft of exterior sidewalls. Please feel free to consult with us on your specific draft requirements.
Directional patterns vs. matte finishes- Some patterns, i.e. matte finishes, are non directional while directional patterns such as leather grains and geometric patterns require added attention in the design and placement in the mold. We can modify patterns to customize the depths and texture characters to assist with your mold design and requirements.
Mold Materials - Our texturing processes and techniques allows for the use of many different metals. Most pre-hard steel types of P-20, NAK series, Px-5, and similar provide good to excellent etching characteristics. Other tool steels (H-13, A series, S-7) provide fair to excellent etching characteristics with some limitations. In particular, S-7 has a tendency to show its grain structure when etched and should be limited to non textured uses. Stainless steel 400 series provide good to excellent texture results. Aluminum T6 or T7 are popular choices and provide fair to good texture results with some limitations. Cast metals have inherent porosity which prevents it from being a good choice for many texture patterns.
At times different materials make mold components that are mated to each other. It is important for us to have this information to properly prepare and texture the mold materials using different processes and techniques to obtain the best results possible.
Mold Finish (Pre-texture) – Prior to texture most mold finish requirements can be met with a SPI C-3 (320 emery finish) while lesser depth patterns (i.e. .001” or less) will need a SPI C-2 (400 or higher emery finish). EDM and cutter marks prevent the tool surfaces from being textured uniformly. Hence, it is important to identify and remove these surface conditions prior to texture.
