Check list for pre-design for plastic injection mould

Preliminary designs (or pre-design) must include the followings: mold number and overrall mold nase size ( Length, Wideth and Height ), view of cavity and core side, longitudinal cross section, steel material type, ejection stroke, tie bars of intended injection machine, top of mold, operator side, part orientation, de-moulding direction, runner and gate location, parting line plane, lifter, sliders, guide pins. Press platen swing study must also be included in preliminary stage.

1- Level of part data for mold design is the latest? Show change index of part in the drawings.

2- Is correct shrinkage used? Show the shrinkage in the drawings.

3- Title blocks to show mold number,injection machine tonnage, shrinkage, part name, part number, raw material, wall thickness, supplier information .

4- Are they any de-moulding concerns that require part concessions? If yes, part de-moulding analysis is required with clear problems explanation and sent to customer for next negotiation

5- Establish mold concept including steel sizes, parting lines, slides, lifters and mechanisms-plan view and sections.

6- Does customer request that mold is designed to run automatically? Yes or No.

7- Locating ring dimensions

8- Cold sprue, hot sprue, or manifold in all views and sections with detail dimensions

9- Show tie bars in view of core side, information of tie bars is provided by customer

10- Show eyebolt holes in all views and sections and ensure that correct size is used for weight of tool

11- Guide pin positions ( one is offset )

12- Part ejection method- show in all views

13- Ejector stroke dimensions

14- Clamping features on four sides of mold. Follow customer request of mold clamping

15- Type of steel, size for blocks and plates

16- Weight of total mold, cavity side and core side

17- Top of mold,operator side or non-operator side

18- Mold injection method shown-knock outs/hydraulic/mechanical spring return

19- Centre lines, section arrows

Approval of the preliminary designs means mold concepts and steel size is OK, so mold maker is agreed to order steel of cavity, core and mold base with steel type confirmed by customer.