Structural Foam Molding

Structural foam molding is known as the low-pressure technique for processing thermoplastics. The molding cavity is filled by the foam from bubbles which is created by the inert gas such as nitrogen which is inserted to the resin. Another process of creating foam is through the gases which are created by the chemical blowing agent. This process is able to create the rigid parts with solid surface.
The common understanding of the foam molding process uses high density polyethylene (HDPE). In fact, instead of using HDPE, this process also uses plastics including polyethylene (PE), polypropylene (PP), and also acrylonitrile butadiene styrene (ABDE).

The main issue is that this process needs low pressure. When the resin flows in the mold, the surface cells will burst to create skins for thicker and more durable walls of the final products. Before the resin come into the mold, the foaming agent is held by an injection screw. Then, the foam which is produced by the inert gases will be inserted to the molten resin so that it will flow further.

Plasti mold

By using structural foam molding, there are some advantages which the manufacturer can take including lower setup cost. Since this process needs lower pressure, the equipment which is needed is economically produced which can result larger parts. In addition, lower internal pressure will also contribute to heavier cellular structure so that the final product will be sturdier.

Commonly, resins are inserted into the mold at 500 degree F and cooled at 100 or 140 degrees F. It can cause the piece to set. In-mold shrinkage can possibly happen. However, it depends on some factors such as type and size of the machine and the thickness of the mold. The structural foam is able to shrink immediately after it is released from the mold. It is commonly able to shrink from 1.5 up to 4 percent of the original size. Commonly, structural foam part can be used in the place of concrete, wood, metal, and also fiberglass.

Plastic Injection Molding

About 2 years ago I purchased a Tool set. It came with a wonderful set of tools, but a really low end, thin and hollow plastic injection molded case that belies the namesake and tradition. Needless to say, the case finally gave up the ghost this past week. I began shopping for a replacement tool box easy for the old set that has since grown to over 200 pieces. Wanting some level of organization that is needed on the trail while off roading, the plastic tool box intrigued me due to it’s thick plastic construction and it’s similarity to a larger tool chest with extendable drawers. Its size and depth allowed me to place it in the same spot as where I held the old plastic injection molded case in my truck.

Plastic Injection molding is preferred for producing complex shapes of various sizes having very fine details. The parts produced by using this method have greater dimensional control. Plastic Injection molding is used for producing parts in large quantities. Plastic molding is widely used for many applications. When you design parts for plastic injection molding, you can arrange multiple pieces in one mold by connecting them with small bars ~0.1″, however the sub-components must not have widely varying volumes. When the design does not allow for additional structures to improve strength, consider using a stronger material, such as glass fiber filled plastic. Consider specifying a fire retardant material when necessary.

Nowadays, liquid injection molding is becoming increasingly important. One reason for this is the increased performance requirements of the finished rubber parts. In addition, more and more producers of rubber parts are seeing the benefits in crown the high level of automation and productivity. Injection molding technology, using liquid rubber, combines the speed, cost efficiency, and versatility of plastic injection molding with the outstanding properties of silicone rubber. It is used in many applications where organic rubber cannot perform, such as military, aerospace, automotive, healthcare applications, etc. The use of silicone rubber combines the properties of resilience, high temperature stability and inertness as silicone is generally unaffected by temperatures from 100 degrees Fahrenheit to 450 degrees Fahrenheit. Progress in liquid injection molding technology has made faster cures possible, enabling unit cost reductions.

The Plastic injection molding machine has two parts: the injection unit which melts the plastic and injects the plastic molding into the mold, and the clamping unit easy which holds the mold. The injection molding unit clamps the mold in a closed position during injection, opens the mold after cooling, and ejects the finished part. Injection molding’s efficiency varies by the number of parts you plan to produce. For a small quantity, such as 10 parts, it may be less expensive to simply machine the desired part utilizing a milling machine. On the other hand, if you desire several thousand parts, injection molding is ideal. When you submit your order for an injection molding part, the websites will assign staff to help evaluate the most appropriate mold material which will vary by part tolerance and number of units anticipated.

Over Molding

Over mold & Over molidng

Over-mold injection molding is the same as insert-molding, where an existing component is loaded into a mold and plastic is molded around it to create a multi-material single part. Insert-molding is most synonymous with combining metal components with plastic in such products as electrical pin connectors. When the term over-molding is used, the metal component is simply replaced with a previously molded plastic part. Single-shot injection molding machines are used to produce both the plastic component and the over-molded plastic. Tooling for injection over-mold injection molding requires two molds; one for the plastic component and one for the over-mold. Over-mold injection molding requires labor to handle the plastic component and load it into the second mold. Over-molding is generally reserved for higher priced parts that can absorb higher machine time and labor costs.

If you are planning to go into a plastic molding business, you should first know the different processes. Choose from a plastic molding process that fits your budget, your expertise, and your resources. In Injection Molding, melted plastic is forced into a mold cavity. Once cooled, the mold can be removed. This plastic molding process is commonly used in mass-production or prototyping of a product. Injection molding machines were made in the 1930’s. This can be used to mass produce toys, kitchen utensils, bottle caps, and cell phone stands to name a few. Plastic molding is a very technical process. It needs experts in this type of manufacturing business for it to be competitive in the market. Therefore, a very scientific and systematic study should be first made before going into this endeavor.

Injection molding is an effective way to make custom parts. Granules of plastic are melted down and then injected into a metal mold; there the molten plastic hardens into a designated shape. Then you open the mold and a new part is removed, inspected and is ready to go. Injection molding is an incredibly versatile form of molding plastics. As with everything, injection molding has its ups and down so it is important that the ends justify the means for your project needs. There are three main components in the injection molding process. The injection apparatus itself which melts and then transmits the plastic, the mold, which is custom designed, and clamping to provide controlled pressure.

Thermoplastic injection molding is molding the most widely used of all plastic processing methods. The injection molding machine reduces pelletized raw material and colorants into a hot liquid. This “melt” is forced into a cooled mold under tremendous pressure. After the material solidifies, the mold is unclamped and a finished part is ejected. Injection molding offers the lowest piece prices available, but tooling prices are generally the highest. Thermoset injection molding is similar to thermoplastic injection molding except that uncured thermoset resins are mixed, injected, and held in the mold until cured. As with thermoplastic molding, the price per piece can be low, but the tooling prices are generally very high.

Purchasing the box, some assorted socket rails, and some additional clips for the socket rails, I took the box home with me to see how well it would stand up as a replacement. The box is quite simple in construction. It’s a plastic injection molded case made of a very thick plastic. The case consists of a flip open lid (with two latches that are padlock compatible) covering a deep top storage area, and three drawers that are very similar to the large rolling tool chests that many professionals and advanced amateur home mechanics have in their garages. When you flip the lid open, the lid will immediately release the latching mechanism for the three drawers. Unfortunately, the lid does not contain any hinges or tethering that prevent it from flopping open and hitting itself on the back of the tool box. This was my only gripe involving the tool box.

Electrical Discharge Machining And Mold Making

   The use of electrical discharge machining is so essential that it is almost impossible to imagine a modern shop without an EDM machine. Many of today’s products simply could not be produced without it. Think of all the cell phones, calculators, IPods, cameras, medical devices and the endless amounts of high tech equipment that are made out of plastic!

Besides the essential role it plays in plastic injection mold making, EDM is used for the precision machining of medical parts, aerospace parts, and other highly specialized products. Electrical discharge machining, including Wire EDM, has also completely changed the way molds are made, as well as other specialized parts.

This is your information source for the EDM die sinker

Graphite  Copper EDM Tooling EDM Oil
EDM Filters Specialty Electrodes Carbide EDMing Surface Finishes

Check out the pages dealing with graphite, graphite dust, copper, dielectric fluid, electrode holders, and machinery.

What about jobs in EDM?

Find out what kind of personality it takes to have electrical discharge machining as a career job. See what the future holds in this high-tech profession.

You can also find educational material that attempts to explain this rather mysterious process. Not so long ago, it was as much black art as science. Today, however, much of the mystery is removed due to CNC controls.

Most shops send their operators to classes put on by the manufacturer of their EDM machine. It is foolish to invest so much money in a machine and skimp on the training! But it happens all the time.

What about EDM and stress?

EDM is quite a stressful occupation, to put it mildly. It may not appear difficult, but the stress levels can be exhausting. Nearly every mold component that is EDM’d is in the final stages of manufacturing. The slightest mistake can become very costly, very quickly.

There is nothing quite like the feeling of coming to work in the morning and seeing your supervisor leaning over the EDM machine staring at your workpiece. Then you find out that you had mixed up two locations and the completely finished cavity block is now completely useless!

Aluminum Die Casting

In 2011, Aluminum Die Casting  industry chain forum, Buhler’s Dr. Lu believes that the success of structural parts of the casting for the automotive industry to bring new development opportunities, die-casting industry in China should actively carry out technological development and follow-up, share casting technology advances.

 Automotive structural parts are installed on the node is the car to form the high-intensity resistance to deformation of the force bearing parts or pieces, with a large size, thin wall, the structure of complex features. In the current production methods, Structual process to adopt a common die-casting machine, with the aid of process measures and optimization of process factors, die-cast automobile part to achieve the industrial production.

 Casting automotive structural parts can be heat treatment, welding and bonding connections, quality and performance fully meet the requirements. Currently casting automotive structural parts have entered the car market in Europe, and gradually spread from the high-end cars to the middle and low range of applications continues to expand. die casting In the automotive powerhouse of China, this production method has been popularized as soon as possible.

Metal Casting

Metal mould casting production guide

This book for the metal type casting production is actual, from theory and practice system introduced in metal mold from design, production to finished product technology base knowledge, operation skills, equipment to use as well as to improve the quality of castings in the methods of content, including metal mold design, casting, metal mold design scheme, Aluminum Casting sand core / shell tribute, casting alloy, heat treatment and casting defect analysis and preventing etc.. The book proceeds the metal mould casting of Gypsies of scientific and technological achievements and commonly used standard, citing a large number of production example, facilitate the reader consults. This book is available in the field of casting technical personnel, management personnel and technical workers in enterprises in practice for reference, but also for professional colleges, research staff to read.

The progress of science and technology and our national economic development, on the casting production raised taller requirement. In recent years. Metal mold casting a wide range of applications, to further meet the needs of industrial and agricultural production, promote the development of foundry production.

At present, in the metal casting enterprises and workers is increasing day by day, I have been to many factories, and are engaged in the work of the business leaders, technical personnel and management staff to carry on the exchange, they all wanted me to write this book of practical technology, so as to guide the practice, make produce detours. Although I am in the nineteen sixties and 70’s, were prepared by the” metal mold design and manufacture”,” aluminum alloy metal casting” two books, but so long. The metal mold casting of science research and production practice, and the emergence of many new results. In order to meet the needs of the community, to further promote aluminum casting China is special casting enterprise development, I wrote the” metal type casting production guide”.

The book to sum up experiences and lessons, and the income of the latest scientific and technological achievements and Chinese and foreign relevant technical standards. In order to reflect the complete book of books, incorporated before I and Xiao Ziqiang Li Ren high school, Zhang Yanwei professor of common research and the preparation of an internal issue book in part; the book castings and tooling design, equipment design and technical parameters, most businesses to support provided by. In this heartfelt thanks to all support the book was written and published comrade.

Limited to the level, the content of the book is inappropriate, adjure a reader.

Zinc Die Casting

A group of Zinc Die Casting faucet, into the copper plating requirements for character, the polished rack to do, always do not like the color of copper, it touches like imitation gold plated color, can not be successfully repeated several times, and plating colors will fade black, is there any way to solve similar or copper color similar to black and fade after plating the problem?


The answer plating plating and die by the poor surface quality and other factors.

     Casting should ensure a good surface quality, can not have loose, cracks, holes, bubbles, shrinkage, cold pattern, defects such as pinholes, or casting surface foaming after plating, electroplating layer from the substrate.

     Grinding and polishing before plating time, careful not to grind too.

     Because die castings during solidification, due to quenching and surface form a dense layer of chilled, and the internal organization may have holes, shrinkage and other defects.

     Do not rub off this good ground surface, or when there will be pitting plating, bubbles, etc. Also, do not weight too tight hot polishing wheel, abrasives and products to prevent adhesions, resulting in poor plating products.

     Easy oxidation of zinc, Aluminum Die Casting China a long time a layer of oxide film formed on the surface, affecting performance.

     Therefore, the removal of the oxide film to have a reducing substance can be acidic (eg hydrochloric acid) solution will be in and out of the surface oxide film