Why injection molding is expensive?
Plastic injection molding processes create the plastic parts by heating plastics pellets to melting point and injecting them into a metal mold. The molten plastic cools and retains the shape of the mold when it solidifies. The injection mold is used to shape the molten plastic. And the injection mold is the most expensive part of the injection molding process.
Why injection mold is so expensive?
- The materials used to build injection mold are expensive.
The materials used to build injection mold are high grade as injection molding needs thousands of pounds of pressure to create the plastic pellets. If the mold is made out of low-grade material, the mold is weak. A weak mold could not withstand high pressure. So, the mold made out of solid materials can stand the time and will no deform under high pressure. The base of the mold is like a case to hold all the mold cavities in place. The base also holds the insert and other parts of the mold together. If the mold size if bigger, the base is more expensive.
- The injection molding cost depends on the complexity of the parts.
The complexity level of the parts affects the injection molding cost. If the parts are complex, more time should be spent on the design and the complex molds. The more complex the part, the more expensive the mold is. When the mold is created for a design, it is impossible to modify. So, when you want to make a severial designer, you need to order new molds. This is another reason why injection molding is expensive.
What does injection molding cost?
To calculate the injection molded parts as accurate as possible, we have to understand all the factors in the injection molding process which include the cost of labor, material, and more.
- The cost of plastic injection mold
Injecion molds can be in different sizes and the price is different. Depending on the complexity, injecion mold costs around one thousand dollars or even tens of thousands. If you need a single cavity mold, you don’t need to order a mold with multiple cavities.
- The cost of polymer resin material
The polymer resin material is an important part of the production, So, the quality of polymer resin affects the plastic injecion molding cost. For example, if the parts are made out of engineering resin wih better strength and chemical resistance, the parts are more expensive than those made out of resin-like polyethylene. If you want to lower the injection molding cost, using recycled plastic materials which are more affordable is another option.
- Labor cost
Labor cost is included in the injection molding cost. It is also a part of custom injection molding costs.
How to lower injection molding costs?
There are some tips to lower the injection molding cost without sacrificing the quality.
- Eliminate unnecessary features
In some certain cases, the numbers of molded parts, textured surfaces, and the company or brand logos may be unnecessary. They need more polymer resin material which will increase the injection molding cost. But in some cases, for example, military application and aerospace part, part numbers are needed and cannot be eliminated. For the words on the injection molded parts, using the mill-friendly font such as Arial, Century Gothic Bold, or Verdana can save some cost. And the depth of the word is around 0.01 – 0.15 inch maximum. The deeper, the more resin will be used.
- Only use finish touches when it is needed
Adding finish touches on the injection molded parts will add some cost. As EDM, bead blasting, polish require extra cost. So, just add finish touches when it is really needed help to save some cost. If the injection molded parts must be polished, you can just polish half or the molds and or the small part need instead of the whole mold to save the cost.
- Injection mold
To save the cost, existing mold can be re-machined to fulfill the new projects instead of creating a new one. But re-machining existing mold is a complicated process. You can upgrade the machines to fulfill your new projects without buying a new one by purchasing the needed parts and replacing the old ones.
- Create the mold in a suitable size
Creating the molds in a suitable size can save stress and cost. The size of a mold means how big the part you are going to design and the quantity you are going to order. Some injection molds are ideal for small parts and low volume. And some injection molds are ideal for large parts and high volume. Creating injection molds in a suitable size is an effective way to lower the injection molding costs.
QA
Q: How much does a injection mold cost?
A: It depends on the complexity of th mold. The cost varies from thousands of dollars to tens of thousands of dollars.
Q: Is injection molding process eco-friendly?
A: Today, modern injetion molding process is eco-friendly beacsue of the efficient machins, durable thermosetting polymers which is able to withstand extreme temperature. But injection molding process is not absolutely environment safe. Injection molding process releases harmful gases which will cause greenhouse effect, but it is controlled very well with moder injection molding process.
Conclusion
Injection molding process is a popular manufacturing process because it is cost-effective to produce a large number of parts. It is expensive especially when producing parts in low volume. If you want to learn more about how to reduce the injection molding cost, contact us today.
