Draft

from Wikipedia, the free encyclopedia

Mold slope , Entformschräge , mold draft or suit is the minimum necessary deviation from the perpendicular to the mold parting in model and mold making . The resulting tapering of the resulting shape makes it possible to dig the finished model out of the mold without damaging it . The design as an addition of material is preferred, whereby the cone can also be designed as a removal of material or the mean value from both possibilities. In the case of surfaces that have to be machined in subsequent production processes, the draft must always be carried out as a material allowance.

The draft depends on the manufacturing method or production process, the model size and the materials used. The quality of the shape in terms of material and surface also determines the resulting slope. It is a necessity and limits the design of manufacturing parts, particularly in metal casting.

All sides of the model that are at right angles to the shape division are provided with a draft, usually 2 ° for small parts. One uses to generate drafts conical cutter , so called die-sinking.

standardization

  • EN DIN 12890: Models, model equipment and core boxes for the production of sand molds and sand cores, June 2000
  • EN ISO 10135: Geometrical product specifications (GPS) - Drawing information for molded parts in the technical product documentation (TPD)

Individual evidence

  1. Basic design rules for plastic parts. Retrieved November 21, 2018 .
  2. Tight (draft) on plastic molded parts. (PDF) HERA AG Kurstoffftechnologie, accessed on November 21, 2018 .