UndercutsModern molding practice dictates certain principles of design which should be observed if molded articles are to be produced successfully.Most elementary is the fact that the piece must be easily removed from the mold after it has been formed. This point…
Flash LinesFlash in injection molding refers to excess plastic material that is extruded beyond the boundaries of the intended part. This excess material can be found in small gaps or seams between different sections of the mold or along the…
ScopeThere is no easy solution to the problems encountered in designing molded articles of plastics. The design will often hinge on what is the best process of molding for the piece in question. The selection of the molding process is,…
Heating The correct heating of hot runner manifold systems is very important and is crucial to the success of the tool in production. There must be good heat transfer between the heater and the surface being heated or the heater will…
opportunities for the production design engineerProduction design work in both the areas of product and process design will provide a rewarding lifetime job. The engineer knows that his work will make possible better products for more people at less cost.…
systematic procedure design for plastic moldingThe road taken by the creative thinker in developing new injection molded parts is long, expensive, and difficult, beset with many detours and byways. A systematic procedure for the development of a product will reduce the…
Thermoplastic Sheet Forming MethodCold bending. Simple circular or cylindrical Vacuum forming or blow molding in female mold shapes. The thicker the sheet, the larger the bend diameter must be to prevent high stress concentrations. Ex: consumer packages.Hot line bending. Two-dimensional shapes…
Design rulesDesigning molded reinforced plastics parts is difficult because of the large number of variables encountered in the material and the process, and the difficulty of controlling some of them. These variables include:composition of the resin, including fillers, catalysts and…
Reinforced Plastics MoldingThe term “reinforced plastics moldings,” as used here and in the plastics industry, refers to parts produced by impregnating a reinforcing material, in the form of cloth or mat, with a liquid thermosetting or thermoplastic resin, laminating the…
The plastic molding process cycleWe are ready to study the actual plastic molding process cycle in the press room inasmuch as we have become familiar with not only the component parts of the mold itself but also the materials which…
