I've worked as a Tooling Engineer. It's tough; machine design is a cake walk in comparison. I am not familiar with the breadth of Aerospace fixtures.<br /><br />Tooling is mostly comprised of Fixtures and Jigs. Jigs are simple setups that use the workpiece as part of the set-up.<br /><br />The purpose of Tooling is to hold the workpiece while you apply your manufacturing process to it. Thus the word 'fixture'. It ain't so much the holding of it as it is holding it precisely, and what's even more important is getting the workpiece(s) in and out of the fixture quickly.<br /><br />Weld fixtures can be all over the map from stuff not much more than a fancy anvil to customer-owned highly specialized productivity focused setup fixtures to pneumatic-assisted work tables designed and programmed to work in harmony with robotic welders. They have to withstand a harsh environment, including the fact that welders like to beat on things with sledgehammers. <img src="/images/icons/laugh.gif" /><br /><br />Drill fixtures are very common. NC (Numeric Controlled) machining centers use a lot of fixtures, but conventional machinists using the Knee Mill and Lathe use very few. Other manual machines tend to call for more fixtures than mill and lathe IME.<br /><br />Metrology fixtures are a whole 'nother animal. These are smallish, precision engineered and custom machined highly precise and highly specialized measuring devices. Used in conjunction with high volume manufacturing IME, using SPC (Statistical Process Control) to make sure your high volume parts are staying in tolerance. An extreme diversity of gadgets are produced for metrology, it's cool stuff. The finest machinists are needed.<br /><br />Sticker shock is to be counted on when customers get the quotes back on what their tooling is going to cost. Many a business plan has been thwarted when the tooling cost projections turn out to be woefully short.<br /><br />There are essentially ZERO economies of scale with tooling.<br /><br />As I imagine <div class="Discussion_UserSignature"> </div>