PP samples (or pre-production samples) are made to test your product’s style, functionality, production process, construction, etc, during your sample development/prototyping process, but are created before your product goes into mass production. They are the prototypes your supplier (typically) creates to develop your product and, eventually, the ‘final PP sample’ represents the precise standard you expect in your mass-produced pieces that come off the line.
If your supplier in China or Vietnam starts to refer to a “PP sample”, they probably refer to the ‘final PP sample’ and, once you approve it, they will consider the product development is confirmed and becomes frozen. Make sure you understand what they mean before confirming acceptance.
Are different PP samples made during new product development, and if so, why?
Yes, because pre-production samples are prototypes made during the new product development process. You need to approve certain elements at several stages. For instance, you may have different PP samples which show iterations of your product with differing colors, finishes, and functionality. They may not necessarily be made using the same processes, tooling, or materials as will be used in the final mass production as they are made by product engineers to test and demonstrate different aspects of the product’s design. For example, a PP sample or two may be made to show the finishes available to you before your final selection is made. If the sample is sufficiently close to what will be made in mass production, they may also be safety or quality tested to assure at an early stage that the product is going to be compliant.
How about ‘Golden samples?’
The golden or final PP sample is the final stage of your prototyping or sample development process. It is a reference point for your supplier when they’re producing the products en masse. It should be made using the same materials and processes as used by operators on the production line.
Your R&D staff, supplier, and quality staff should all have a copy of this final PP sample. It can be used to refer to in order to assure that the pieces fulfill your expectations.
If some of the components of the product necessitate some tooling, make sure the ‘golden samples’ are made of components made with that tooling alone. Anything pre-tooling is NOT final when it comes to the approval of samples before production. For example, for a plastic casing, the mold may come with flow marks, injection gate marks, and other visual impacts on the product. The physical properties will also be different when compared with 3D printing.
Is one sample enough?
No. As we wrote above, different parties need to keep at least 1 sample in hand.
In addition, sometimes a tolerance on a certain aspect of the product is hard to quantify. Boundary samples may also be needed in order to show what is and is not acceptable within a limit you can accept. For example, with colors, these samples can show the perfect color and also which lighter and darker shades are acceptable. If a piece is produced which is lighter or darker than those boundary samples, then it is clear that there is an issue that needs to be fixed and that you have grounds to raise a complaint to the manufacturer.
Should final golden samples be connected to your manufacturing agreement and quality standard?
Yes. These all complement each other.
Your expectations should be written down in your manufacturing agreement and QC checklist, but in the case of tangible elements of a product, such as its color and finish, this is where PP samples can be used to physically see and experience your expectations.
Where to learn even more about pre-production samples?
Try these blog posts:
- The Role Of Pre-Production Samples
- How much should importers pay for pre-production samples?
- Challenges with pre-production samples
You should also listen to this episode of our podcast: Why is a pre-production sample so important?