, 06-17-2026, 08:43 AM
🤖 In the meantime, here’s a response from the [FEDEVEL AI HW Assistant]().It helps to find relevant resources for your question, but it may make mistakes as it’s still in early development.This is the response from the AI Assistant:The 0.013mm offset in Altium's 3D body placement appears to be an intentional design choice, though the exact reason isn't explicitly covered in the available training materials. Based on general PCB design practices and Altium's typical behavior, here are the most likely explanations:1. **Manufacturing Tolerance Buffer** This small offset (~13µm) likely accounts for real-world PCB manufacturing tolerances. Solder mask thickness typically ranges from 10-25µm, and this separation prevents the 3D model from appearing embedded in the solder mask layer. [Relevant placement precision discussion](https://www.youtube.com/watch?v=PqFtSpAXB9Q&t=4026)2. **3D Rendering Optimization** A minimal offset helps prevent "z-fighting" visual artifacts in 3D views where surfaces at exactly the same height might cause flickering. This is common in 3D CAD systems.3. **Component Floatation Prevention** The offset ensures components don't appear partially submerged in the PCB substrate, which could happen with perfect alignment due to rounding errors in coordinate systems.4. **Assembly Realism** In actual assembly, components sit slightly above the PCB surface due to solder paste and pad geometry. The offset mimics this real-world behavior.While the videos show 3D placement techniques, they don't specifically address this 0.013mm offset. For precise control, you can manually adjust the Z-axis position in the 3D Body properties after using the alignment tool. Many designers use this small gap as visual confirmation that the 3D model is properly positioned without being embedded in the board.You can continue chatting with the AI Assistant here:https://fedevel.com/hw-assistant