CAD Data You Can Trust

About this book

A CAD file is rarely alone. A drawing depends on a model, an assembly depends on hundreds of parts, and a bill of materials depends on all of them carrying the right numbers and descriptions. On a shared network folder, those dependencies are held together by file paths and good intentions. They hold until someone renames a folder, saves a copy over the original, edits an old version or restores last month’s backup. Then the office discovers how much of its engineering record depended on nothing more than everyone being careful.

This book is for the people who must keep engineering data trustworthy in a small business: the engineering manager who answers for what is released, the CAD administrator who looks after the files and the IT person who keeps the servers running. It works through the problem in a practical order: what shared folders cost, part numbers and file names, references, revisions and release, lifecycle states and permissions, migrating into a data management vault, backups that have been restored, licences and workstations, upgrades, and exchanging data with suppliers. Each chapter ends with an exercise and its worked answer.

It assumes working knowledge of a parametric CAD system and of how drawings are released. It is vendor-neutral. Product data management systems differ in their terms and screens; the chapters explain what to decide and how to test it, and leave the configuration steps to your vendor’s current documentation.

The running case

Every chapter follows one fictional engineering team. This is an illustration. A small Australian manufacturer of stainless-steel pump skids has nine CAD users: two engineers, five designers and two drafters. Fourteen other staff in production, purchasing and quality view drawings but do not model. For years the team has kept its CAD data on a shared drive, where a scan finds about 41,600 files occupying 186 GB. Each skid combines a pump, a motor, a baseframe, pipework, valves and instruments, so a single change to a common part can reach dozens of assemblies.

The team decides to move its data into a product data management vault. The chapters follow that decision from measurement to migration and on into daily operation. Money is in Australian dollars at an internal cost rate of A$95 an hour; internal labour carries no GST, and bought items are shown excluding GST. The business, its people, files, times and costs are invented. None of them describes KEVOS® work, a real company or the performance of a real software product.

Source limits and professional responsibility

The supplied source was a 2010 book on administering one CAD product and its workgroup data management system. It shaped the list of subjects this book covers, but its instructions are out of date and nothing in its text, figures or procedures has been reproduced. Recovery terms follow NIST SP 800-34, and Australian cyber-security context follows the Australian Signals Directorate’s Essential Eight guidance; both were checked for this book and are cited where used.

Data management protects the engineering record; it does not make the designs in it correct. Release and approval remain the responsibility of competent engineers. Backup, security and licensing decisions involve your IT provider, your software vendor’s licence terms and, for regulated products, your customers’ and regulators’ requirements. Use this book to ask better questions and test the answers, and take specific advice where the consequences warrant it.