Reverse Engineering Focused on the Plastic Injection Molding Process

At Rebling Plastics, reverse engineering is much more than simply copying an existing design. With the advent of new engineering materials, many manufacturers are able to replace expensive machining operations on metal parts by using multi-cavity plastic injection molding. Using appropriate wall thicknesses and utilizing ribs and bosses allow the part to be robust without adding weight, which can significantly affect processing time and cost.

We keep the plastic injection molding process in mind throughout the design phase of reverse engineering. By designing parts for manufacturing, we can maintain consistent quality and keep costs to a minimum. Tweaking of certain features may allow for less expensive tooling and better processing. Rebling Plastics engineers can also recommend appropriate plastic injection molding materials for new or reverse engineered parts.

Rebling Plastics uses SolidWorks 3D CAD software to design parts for plastic injection molding. To reverse engineer more complex designs, we use a RAM Optical CNC Inspection Unit. From this device we can collect precise 3D measurements. These measurements can be used to take measurements of a sample part and automatically compare them to prototype and production parts.

Reverse Engineering Case Study: Lens Cleaning Station

Recently Magic Safety Products, a new customer, came to Rebling Plastics with a plastic injection molding project. They wanted to take an existing lens cleaning station for safety glasses, and make their own version with their company’s label. With a sample of the box and its contents and no drawing, Rebling Plastics engineers quickly made a 3D CAD model in SolidWorks, and recommended an appropriate material for plastic injection molding.

While reverse engineering all the features, we made a couple minor changes to help the process of labeling the customer’s part and improve the quality of the plastic injection molding process. The customer had no CAD software, so we converted the files to eDrawings, which can be emailed and viewed without installing any software. After approval of the design, we made a SLS rapid prototype out of a similar material to the chosen plastic injection molding material.

The prototype was checked for assembly with itself and the cleaning tissue and spray bottle. After the customer signed off, the plastic injection molding tool was built, and production began.

Reverse Engineering Case Study: Molded Electrical Receptacle

Shiloh Industries, a customer of Rebling Plastics for several years, recently wanted to expand their product line to include a special electrical receptacle. They had a similar part to work from, and a 2D drawing of the major outside dimensions. They came back to Rebling Plastics for some reverse engineering assistance and production of the new part.

After recommending a plastic injection molding material, Rebling Plastics engineers quickly worked to convert the drawing to a 3D CAD model. The rest of the details were reverse engineered, and draft angles were added to the old design to improve consistency in the molding process, and therefore improve quality. An eDrawing was sent to Shiloh for approval. Shiloh engineers were able to take measurements of the newly added details and make a few changes to the existing part design.

Once the changes were made and approved, a rapid prototype made of a plastic injection molding material was sent to Shiloh. After prototype approval, production parts were only a few weeks away.