It is not uncommon to find out that your prototypes and initial limited production runs are not exactly the same as each other. It could be slight variations in specs, color, dimensional tolerances, improper fit or even performance issues with function.
How do we keep this from happening? Most importantly, how do we reduce the risks going from prototype to production?
One of the most valuable things that we produce as a manufacturing company is what we call our process engineering documents or specifically the Control Plan. This document will literally show and tell a factory how to make a product and measure it in step by step instructions. It is the manufacturing recipe. These are the raw material selections, quality procedures, tolerance specifications, instructions, and test procedures provided to each individual station on the production line.
Process Control Documents (or Process Control Diagram) lay out exactly how each component is to be made, how each component is to be assembled, and control metrics to ensure each step of the production process is correct, each time!
Photographs are an excellent tool through the process as they show both visual "accept" vs "reject" components and measurement tools in use. A Control Plan will include dimensional drawings, provide measurements and specific tolerances, provide the necessary tools and testing measures to ensure specifications as well as form and function is met with every component. You will develop as many process control documents as you need in order to ensure the production team understands how to execute flawlessly each time.
There is no substitute for being on-site for the first production runs. No matter how good the factory is, how experienced your managers are, or how strict your 3rd party QC team can be, NOBODY cares about your product they way that you do. We ALWAYS have engineers on site for the first production run of every product that we release. In fact, we have engineers on site for tooling set-up, pre-production planning, inbound quality control, and inspection of finished goods prior to shipment.
We have engineers on-site until they are comfortable that the production facility is comfortable with the Control Plan and are using it. We are relentless about having engineers on site to assist, audit, or correct any part of the Control Plan during the life cycle of the part. Having our engineers ensure products are made with the right material to the right specification is how we ensure YOUR success!