Starting the Development Process

It is helpful to have a description of how the development process typically works. To make the process easy, Custom-Pak provides free design services. We have three mold building facilities, a machinery manufacturing operation, six blow molding production plants, an automation facility, a recycling & compounding plant and full service warehousing & distribution.

Basic Quantities

Custom-Pak has some of the fastest set-up times in the industry. Even so, production set-up on a blow molding machine can be time consuming and costly. We suggest minimum quantity releases of 1,000 parts at a time to reach economical levels. Blow molding remains the economical choice for quantities into the tens of millions. When you tell us your quantity expectations, we provide the most cost efficient approach to produce that quantity.

Project Concept

Do you have an idea in your head or do you have 3D CAD models with detailed specifications? We can help from any starting point. Rough price estimates can be made from very limited information. We work with you to establish basic size, shape and material needs. If our initial pricing falls within your project parameters, it is time to move into the design phase.

Part Design

To get an accurate quote, we prefer to create a 3D model of the part and establish specifications . We offer our product design assistance at no charge. The detailed part designs allow us to provide realistic part & mold quotations, and set project time-lines.

Our designers use Solidworks and Seimens NX software to create 3D part models of the blow molded parts and we can work with anyone’s software that can export files in STEP (.stp), PARASOLID (.x_t), IGES (.igs) and similar formats. If you already have a design, you can email it to along with any other requirements you want to include in your request for quote (RFQ). We also provide an FTP site and a ShareFile option for transferring large product design & assembly files.

Mold Design

A high quality blow mold is a very important part of any blow molding project.

Once you approve the part design and project budget, we begin the mold tooling design. The mold design details like blow ratios, parting line locations, cooling patterns, ejection needs, blow methods, venting locations and in-mold systems are reviewed by engineering and production teams. We encourage customers to review the mold designs with us before molds are made.

Mold Building

Most blow molds are CNC machined from high grade Aluminum alloys that provide rapid heat transfer for efficient part cooling. A typical mold takes 6-10 weeks to build. Blow molds built at Custom-Pak are maintained for the life of the product while in our possession. Mold prices include sampling on a production machine. This eliminates divided responsibility, saving you time, money and hassles. However, customers may choose to work with other mold builders. We only ask that their shops coordinate mounting details with us before shipping the tools to Custom-Pak.


Manufacturing teams use an enterprise software system to schedule material deliveries, schedule set-up & run times, monitor production efficiency, track QA inspections, complete pack-out and direct all other project activities. Part production occurs on one of over 200 blow molding production lines. We typically assign one of our six molding plants to your project so the people from that plant are familiar with all the small details that make your product a success. Plants run 24/7. Even with all of this capacity, our services are in strong demand so lead-times can run up to 6 weeks if accurate forecasts are not available.


All Custom-Pak plants are ISO9001-2008 registered. We have used Just-in-Time, Lean, Kan-ban & 5S plant work flow methods for many years. By building and programming blow molding machines and integrating them with robotics, we have developed repeatable process control for true Six Sigma production capability. Not every project can begin with this capability so we provide “computer vision” inspection, leak detection, coordinate measuring, optical comparators, x-ray analyzers, colorimeters, sonic meters, special gauges and many other calibrated systems to provide you with world-class quality.


From 1 carton to 100 truckloads in a single day, we deliver on-time. We can offer storage and drop-shipping services if needed. To keep overall costs low, we expect customers to pay for delivery costs.

How we are compensated.

We accept checks, credit cards and for larger accounts we will review your credit report. With good results, we provide credit terms. Credit terms for molds are 50% down with the tooling purchase order and 50% due upon sampling the completed mold on a production machine. For part production our credit terms are net 30 days, FOB our production plant.