When DiMonte Group completes an engineering project, you get a package that includes not just manufacturing documentation, but also all the source files.
Not only can you manufacture the product in your factory, or at your chosen contract manufacturer, you also have what is needed to maintain and extend the product—fix manufacturing issues, replace obsolete components, and add new features.
When we are commissioned to revise existing products, designed for our clients by other firms or contract manufacturers, it is surprising how often the fundamental design details are missing!
Our clients often assume that since they have the manufacturing documentation—for example, a bill of materials and Gerber files to make PC boards—then changes should be easy. We should be able to modify the existing design with minimal effort, and without re-inventing the wheel.
But if the client does not have the original engineering source files that were used to generate the manufacturing documentation, then it is really difficult to make changes.
In short, the client doesn’t really own the design!
CASE STUDY
(Details modified to protect the innocent.)
Our fictitious customer designs, manufactures, and sells plastic injection molding machines. Their engineers are experts at plastic resins, machine tooling, and injection molding generally.
They needed a control module, an electronic brain, to handle temperature sensing, heater control, and motor control. The control box needed a keypad to program the machine, with a display to monitor machine operation.
A few years ago, they turned to a contract manufacturer (CM) who offered a one-stop shop: both design and manufacturing. The client was happy because the engineering costs were minimal, largely buried in the price of the product. Initially this worked well. But after a few years, the relationship had gone south. The client was unhappy with product quality and pricing. The CM was unhappy about product volumes. When product changes were requested, the CM was reluctant to make them.
The client decided to explore other alternatives for design and manufacturing. They requested the product documentation. The CM provided manufacturing documentation but claimed that the source files were their property. As a result, to add new features, we had to reverse-engineer the old hardware and redevelop all the firmware. An expensive education in product ownership!
PRODUCT DOCUMENTATION YOU NEED
There are two categories of product documentation that you need to really own your product design: manufacturing documentation, and source documentation. Too often our clients get only the manufacturing documentation.
MINIMAL MANUFACTURING DOCUMENTATION
MECHANICAL PARTS:
- Bills of material.
- Product prints (2D drawings), showing materials, dimensions, finishes, and tolerances.
- Assembly drawings.
ELECTRONIC PARTS:
- Bills of material
- Gerber files (for making raw PC boards)
- Pick and place files (for automated placement of components on boards)
- Wiring diagrams (for cables)
- Firmware (object code that gets programmed into a microcontroller)
SOURCE FILES
While all the above items are necessary, they are not sufficient to maintain and support a product. You also need the source files that were used to create the data.
MECHANICAL PARTS:
- Original 3D CAD files for every custom mechanical part and assembly. These should be native CAD source files, not STEP/Parasolid/IGES translation files. For example, if generated using SolidWorks, .sldprt/.sldasm/.slddrw, not .stp/.x_t/.igs/.dxf/.pdf
ELECTRONIC PARTS:
- Original CAD files for the schematic diagrams and PCB layouts. For example, if generated using Altium, .SchDoc (for the schematics), .PcbDoc (for the PCB layout). Not just .PDF and Gerber files.
- Documentation describing which CAD system, and which release was used. (DiMonte Group uses Altium, but we can import CAD source files from many electronic CAD tools.)
- Original source files for all the software. For example, .C for programs written in the C language. Not just the object files that are programmed into the microcontroller, .obj/ .hex.
- Documentation describing which compiler/assembler tools were used to generate the software, and their release versions.
- Documentation describing which tools are needed to program and debug software, for example, JTAG tools.
CAN’T GO BACK
For a mechanical part, if we are only given the manufacturing files, and we need to modify the component, we are going to have to remodel the part in CAD. There is no efficient way to go back from a drawing to a model.
For a PC board, if we just get the Gerber files, and we need to add a component, we are going to have to redraw the schematics, and remodel the PCB layout. Reverse engineering a PCB without source documentation is tedious and expensive, often as much time as to develop the PCB from scratch.
For software, if we just get the program files that are loaded into a microcontroller, and any changes are needed, we are going to have to rewrite the software, which means fully understanding all the operational details of the product and coding it all up. We can’t go back from program files to source files.
THE MORAL OF THE STORY
At the outset of an engineering project, make sure that your provider agrees to provide you not only with manufacturing documentation, but also complete source files.
When DiMonte Group delivers an engineering project to you, you always get both.
That’s the only way you really own your product.
