Tolerance Stack-Up Analysis in Mechanical Assemblies Every assembly is a stack of tolerances. The clearance that the drawing promises is really the sum of the machining variations, and the sum is what decides whether the…
Jig and Fixture Design for Reliable Machining The part that is held wrong is the part that is made wrong. The workpiece that flexes under the cutter, the part that shifts between the operations, and…
Mechanism Simulation: Checking Motion Before Metal Is Cut A linkage looks smooth in the sketch and binds in the prototype. The four-bar that seemed to swing through the range hits the limit at the wrong…
GD&T in Mechanical Design: The Language of Fit A drawing without tolerances is a wish. The part is machined, the holes are drilled, the surfaces are cut, and the assembler discovers that the parts do…
Parametric Modeling Discipline for CAD Users Parametric modeling is the reason the design change takes five minutes instead of five days. The dimension is changed, the feature rebuilds, the related parts follow, and the assembly…
Lightweight Design and Topology Optimization for Machine Parts The heavy part costs material, energy, and handling time. The light part that does the same job is the better part, as long as it was light…
Rapid Prototyping for Mechanical Design Teams The prototype used to be the expensive proof at the end of the project. Now it is the cheap question at the beginning. The machine builder who prints, machines,…
Custom Machine Design from Specification to Handover A custom machine starts with a vague sentence and ends with a running machine in a customer plant. Between those two points, most projects lose time not on…
Standard Parts and Design Reuse: The Quiet Productivity Lever Every machine shop has a drawer full of special parts that could have been standard parts. The special bracket, the custom plate, the one-off hinge each…
Assembly Modeling That Survives the First Prototype A 3D assembly that looks perfect on the screen falls apart in two ways. The first way is mechanical: the parts do not fit when they arrive. The…
Finite Element Analysis for Machine Builders: When It Helps and When It Lies Finite element analysis looks impressive on a screen, but a mesh is not the truth and a color plot is not a…
CAD Data Exchange That Does Not Destroy Your Geometry CAD Data Exchange That Does Not Destroy Your Geometry CAD data exchange is the silent tax on every multi-vendor machine project. The STEP file looks fine…
Motor Sizing for Machine Builders: Torque, Inertia, and the Duty Cycle Motor Sizing for Machine Builders: Torque, Inertia, and the Duty Cycle Motor sizing looks like a catalog exercise, and that is exactly why so…
Tolerancing Strategy for Machines That Must Fit Together Tolerancing Strategy for Machines That Must Fit Together Tolerance is where mechanical design stops being art and becomes accounting. The drawing says 0.05 mm, and the shop…
Design Reviews That Actually Find Problems Design Reviews That Actually Find Problems Every engineering department runs design reviews, and most of them are ceremonial. The drawings get flipped through, the schedule gets discussed, and the…
