Once it has been determined where draft needs to be applied to a part design,
the next question is: "How much draft is required?" To address this question, NADCA Specifications
for Draft Requirements are used. The draft requirements are available in two levels, Standard and
Precision. In this example, the Standard Draft Requirements will be used for most features
and the Precision Draft for one critical feature. The Standard draft level should be used whenever
possible and the Precision draft level should only be used when the design absolutely requires
minimal draft on a feature. Normally draft is not calculated for each individual feature, but rather
the specification is used to establish a general draft angle for a majority of features with exceptions
in critical design areas. To determine the exact draft required for a part wall or feature of a specific
depth or height, formulas are used.
For the section on draft from the "NADCA Product Specification Standards for Die Castings,"
click here.
For complete design information, refer to the "NADCA Product Specification Standards for Die
Castings" publication available
Online,
CD,
or
Print.
