Our 5 Top Key Points for Mold Design

Are you working on a new injection molding project? You might have some concepts about how to manufacture your products. To ensure you can get high quality parts in short time frame, we would like to share our 5 important points that may help you to kick off your rapid tooling or Rapid Prototype Tooling project.

1. Layout, layout, Layout: Layout is one of the critical aspects in mold design, it relates on how we set the injection point, parting lines and ejection system etc. When you send us your initial 3D model, our experienced engineers use mature techniques to stimulate and define how to layout your part in the mold. Some parts in same or closed size, we would suggest to make a family mold. In that case, the tooling cost can be cut down without compromising the quality.

2. Process: optimal process always helps to get high quality injection mold parts.

Gate Type : Direct gate, Side gate, Sub gate, Tunnel Gate, Pin Gate are some common gates in injection field. Part size, injected material, part structure have strong relationship of choosing which gate typ. Meanwhile, we need to bear in mind that remove of the gate also leaves a small “scar” on the part, how to minimize and hide this scar is one of considerations. Proper Gate can shorten the injection cycle time and mold parts quickly.

Shrinkage: Shrinkage on different material is differ, set the mold shrinkage according to material’s properties. Due to some part may have quite uneven wall thickness, adjust shrinkage partially is necessary sometime.

Parting line: parting line should be connected smoothly, try the best to avoid sharp corner and avoid going through the visible surfaces.

Cooling: the purpose of setting cooling system (water lines, cooling well, beryllium copper cooling) is to bring down the mold temperature and raise the production efficiency.

Ejection: please bear in mind that ejection marks can be seen if you mold the part in transparent, you need to set the ejection skillfully and choose the best ejection way (ejector pin, ejector block, striper etc) for your molded part.

Hereby, DFM (Design For Manufacturability) is necessary for figuring out all the potential issues  before cutting the steel.

3. Mold Steel : Al 7075, P20, S136, NAK80 are some popular tool steels in china. They have different properties, S136 & NAK80 are recommended as polishing steel for high gloss parts.

Typically, mold in P20, S136, NAK80 steel can perform longer life time, mold maker will base on your rough required quantity and part finish to suggest the best tool steel.

4. Draft & Texture: Draft allows the plastic parts to be ejected successfully. Typically, 0.5~1 degree draft angle is enough for gloss finish parts. For texture finish part, the roughness of texture affects the big or small draft, the draft degree can be known by reading texture code book. If design and assembly permission, the bigger draft is better. Draft marks happens on molded part if without proper or in small draft, the life time of mold will be shorten by repeated wearing.

5. Injected Material: Injected material has strong relationship with mold shrinkage, mold steel, draft, we need to double confirm the injected material before mold design.

We are a professional mold manufacturing company. Our engineering team has many years of experience in mold manufacturing, and whether it is a simple mold or a complex mold, we can provide you with the best solution. Contact TEAM Rapid for the best advice on your next rapid tooling or Rapid Prototype Tooling project.