Draft: angles incorporated into your part design to aid in the ejection process from the mold machine.
In general, 2 degrees of draft should be the standard in your part design to maintain uniform wall thickness.
Angles or tapers that you incorporate to key features of your parts such as ribs, walls, posts and bosses that lie perpendicular to the parting line of your part will help to ease the ejection process and eliminate problems when running your injection molded plastic parts.
Less draft will sometimes lead to damaging of your parts during ejection. Also with plastic molded parts with little or no draft a mold release agent may have to be used which can cause unwanted reactions and blemishes and may produce additional costs to your finished plastic parts.
Plastic parts should be designed with draft to prevent sticking and ejector pin push marks on the show surface during the molding process.
Also, an adequate amount of draft is needed for surfaces that will be textured.
Plastic parts should be designed with draft to prevent sticking and ejector pin push marks on the show surface during the molding process.
Don't forget ribs should not exceed 60% of wallthickness.
The article comes from China injection mold manufacturer - Mold Best Assurance Company Limited, website is www.mbamoldanddesign.com
