Why Plastic Injection Mold In The First Place?
Plastic injection molding has enjoyed global success as a manufacturing solution. Most notably, its popularity include the affordability of the process, and the production speed. We acknowledge the time and money saved over the long run. However, the build and test of the mold still takes significant timeframe prior to production.
What is the Lead Time for Plastic Injection Mold?
A simpler definition of the phrase “lead time,” is the total time needed to get a product. That is, from when a purchase order is placed, until when the item is finished. Hence, the lead time starts from the moment the maker of the mold receives the PO for a mold. It will ends when the finished item gets delivered to the company that made the order.
The project management steps involved for the manufacture of a plastic injection mold could happen in the following manner:
- Purchase Order Received
- Kick off Project
- Understanding Customers’ Standard Requirements and Needs
- Tooling Design
- DFM Analysis
- Customer’s Confirmation to Proceed
- Manufacture of Mold
- T1 Sampling of Mold
- Quality Control and Quality Assurance Checks and Reports
- Ship Sample Parts to Customers
- Customer Feedback
- Tweaks to Mold if applicable
- Customers Confirmation to Ship Mold
- Follow up on Mold Performance
Historically, the lead time for a plastic injection mold can be as long as 36 weeks! In some cases, it was more. However, today, due to technology and the maturity of manufacturing processes, lead time has significantly decrease.
So, how long is the lead time for the manufacturing of a plastic injection mold?
Typical lead time could take 3 to 4 weeks for a single cavity prototype mold. This estimate is suited for low production volume of about 450 to 1000 samples, a simple cooling circuit, and a couple of minimal ejector pins.
On the other hand, multiple cavity injection or more complex molds could take as long as between 1 month to 6 months. More complicated molds typically has higher production volume between 100,000 to 1,000,000 injection molded parts, multiple cooling channels, multiple actions like slide cams and lifters, as well as complex ejection mechanism.
Other long lead time factors could be due to type of feed system such as multiple nozzle hot manifold, a high surface finish, and tight-tolerance dimensional requirements. Purchase of specialized components such as hot runner systems and imported accessories could also add more time to the existing timeline.
It is also imperative to note that low volume production molds usually utilize metals that are softer (unless requested by the customers), and have the ability to be cast, before being machined mechanically on CNC mills. For the case of a high volume production mold, then there is the need to make use of steels that are very hard, and the usual method of machining such type of steel is CNC machining and spark erosion; where electric sparks are used to shape the steel inserts. The latter can be a rather expensive and slower process.
Factors to Consider
To be more precise, these are the several factors to consider and reconsider when it comes to the lead time of a plastic injection mold, and these factors include the following:
- Part Size
The size of the part is an important factor to consider. The bigger the part, the more time spent on the production. Invariably, it means that the smaller the part size, the lesser the lead time.
- Part Design
Another factor to consider is the design of the part. The more intricate the design, the longer the lead time. Hence, the simplicity or complexity of the part design is the determinant of the length of lead time.
- Mold Steel
Depending on the nature of the part to be created, it could either be created with softer steel or harder steel. It is important to note that when harder steel is used, the process becomes slower. In comparison, if the soft steel was used, lead time can be shorter.
- Mold Cavity
There are two ways to this, the single cavity plastic injection mold, and the multiple ones. Multiple cavity molds are cheaper (per piece price) than single cavity molds, and they also save time.
- Customer Requirement and Testing Phase
It is imperative to pay attention to the standards and requirements of the customers, prior to execution of the project.
Typically, a plastic injection mold takes about 3 to 4 correction loops and 1 to 2 months of repairs and maturation before the desired results can be achieved. As pointed out earlier, it is all dependent on the factors aforementioned.
- Factory’s Workload
Another factor that may be considered is the workload of the manufacturing company. If the manufacturing company’s full capacity has been reached, then lead time could take longer.
In most cases, the lead time for the completion of a simple mold can take from four to six weeks, while a complex mold can be completed within six to eight weeks. Furthermore, an aluminum mold (most probably a prototype) could take between two to three weeks. However, as always, it is all dependent on the mold’s fabrication, the complexity, and several other factors. Basically, while some manufacturing companies may have different ways of making shortening the lead time, the differences in lead time are minimal.
Innovative manufacturing technologies helps shorten the lead time. Technologies will keep getting better. Hence, there is every possibility of the whole plastic injection molding process will get better in the near future.
Nowadays, with automation and robotic technologies, lead time can be shortened further. In recent years, we have seen major improvements in how technologies have helped the manufacturing sector.
- Quality Checks
High demanding parts could take a longer time for inspections and checks. Depending on the customers’ needs, QA/QC checks timing could differ greatly.
Some customers are experimenting, thus, the research and development and this will affect lead time as well. Chances are they are testing manufacturing methods, new materials, new designs and so on.
There are simply a lot of determinants to the lead time of the manufacture of a plastic injection mold. Examples include types of molds, technology used, quality checks requirements, whether R&D is involved, and many more factors.
Typically, molds are completed within 3 to 5 months time. Prototype molds take 1-3 months to build, unless customers have the desire to explore product development (R&D).
Keen to discuss how long it will take to build your products? Contact us today and we’ll be more than happy to assist you.