Reverse engineering is revolutionizing product development, offering a powerful bridge between the physical and digital worlds. By combining 3D scanning and 3D printing, professionals and hobbyists alike can rapidly create digital designs from existing physical parts. This synergy streamlines workflows, accelerates prototyping, and opens up new possibilities for customization and innovation. Imagine being able to replicate a broken component without original blueprints, create perfectly fitting parts for legacy systems, or design bespoke products that integrate seamlessly with existing items – all powered by the combined strengths of 3D scanning and 3D printing.
In this guide, we will delve into the step-by-step process of reverse engineering, focusing on how to effectively use 3D scanning to capture physical forms and prepare them for 3D printing. We’ll explore essential tools, from advanced CAD software to high-resolution 3D scanners and precision resin 3D printers, providing practical tips to optimize your workflow and achieve superior results.
For an in-depth exploration of 3D scanning technologies and workflows, we encourage you to download our comprehensive white paper.
Download the White Paper
Are you considering a 3D scanner to complement your professional 3D printer? Explore our detailed guide on selecting the ideal 3D scanner for 3D printing applications.
Webinar
3D Scan to 3D Print: Rapid Reverse Engineering for Machine Restoration, Assembly Jigs, and Aftermarket Products
Discover how integrating 3D scanning into your workflow, combined with reverse engineering CAD and 3D printing, can significantly enhance part design and production efficiency. Watch this webinar to learn more.
Watch the Webinar Now
Bridging the Gap: Understanding Meshes and Solid Models in 3D Workflows
A fundamental hurdle in translating physical objects into the digital realm lies in the distinction between two primary types of 3D models: meshes and solids. This difference is critical to understand for effective reverse engineering and utilizing 3D printing.
3D scanners inherently produce mesh models. Think of a mesh as a digital net cast over the surface of an object, composed of numerous interconnected triangles. This format, often represented as STL files, is directly compatible with most 3D printers. However, mesh models are purely surface representations. They lack inherent design intelligence or parametric data, making them difficult to edit directly in CAD software for design modifications. They are essentially a collection of points in 3D space defining the shape, but without the design history or feature information.
Solid models, on the other hand, are the cornerstone of engineering design. Created in CAD software, solid models are built using parametric features and a design history. This means the model is defined by a series of logical steps and design parameters. For example, a hole in a solid model isn’t just a void; it’s a feature with defined diameter, depth, and position, all of which can be easily modified. Solid models hold the ‘intelligence’ of the design, allowing for flexible and precise edits. Engineers prefer working with solid models because they enable design iterations, simulations, and manufacturing preparations with greater control and accuracy.
The challenge in reverse engineering arises because 3D scanning yields meshes, while design modifications and advanced engineering tasks typically require solid models. To bridge this gap, the mesh data from a 3D scanner needs to be converted into a parametric solid model. This conversion process is the essence of reverse engineering, enabling users to leverage scanned data for design improvement, adaptation, and 3D printing of functional parts.
WEBINAR
Elevating Product Development: How 3D Scanning Integrates with Modern Workflows
Join Peel 3D in this webinar to discover how seamlessly integrating 3D scanners into your 3D printing workflow can revolutionize your product development process, fostering innovation and efficiency.
Watch the Webinar Now
Step-by-Step Guide: Scanning for 3D Printing in a Reverse Engineering Workflow
Reverse engineering becomes indispensable when you need to recreate parts for which original CAD designs are unavailable. This is common in scenarios involving legacy equipment, damaged components, or when adapting existing products for new applications. By using 3D scanning and 3D printing, you can create accurate replacements, customize existing products, or design complementary parts that fit perfectly with off-the-shelf items. Let’s explore a practical example: creating an assembly jig for an aftermarket digital gauge designed to fit a Volkswagen Golf’s air vent.
1. Object Preparation for Optimal 3D Scanning
Preparing your object is crucial for achieving high-quality 3D scans. Applying a temporary matte coating spray is often recommended to enhance scan accuracy. Even slightly reflective surfaces can scatter the 3D scanner’s light or laser, degrading data quality. Highly reflective or transparent surfaces are particularly problematic and may be impossible to scan accurately without a matte coating. These coatings create a uniform, non-reflective surface that the scanner can read effectively.
Applying a temporary matte powder to your object enhances 3D scan accuracy.
2. Capturing the Object’s Form with a 3D Scanner
Employ a high-accuracy 3D scanner to capture the essential geometry of your object. For reverse engineering tasks demanding precision, tabletop structured light or laser scanners are ideal choices, offering accuracy levels of ±100 microns or better. These scanners project light patterns or lasers onto the object and use cameras to capture the distortions, calculating the 3D surface data with high fidelity.
3D scanning an aftermarket part to capture its precise dimensions for reverse engineering.
Note: Objects with complex geometries or deep recesses may require multiple scan orientations. Carefully repositioning and rescanning the object from different angles ensures comprehensive data capture, eliminating shadow areas and ensuring a complete 3D model.
3. Refining the Mesh Data for CAD Compatibility
Raw scan data from 3D scanners can often result in very large mesh files. These files can be cumbersome to work with and may slow down subsequent processing in CAD software. Scanner software typically includes tools to refine the mesh, repairing minor gaps, smoothing surfaces, and simplifying the mesh by reducing the triangle count. This optimization step is vital for creating a manageable and efficient dataset for reverse engineering. Aim to reduce model complexity while preserving critical details and dimensional accuracy.
Tip: For advanced mesh editing and refinement, consider using software like Meshmixer. Meshmixer offers a comprehensive suite of tools for mesh cleaning, sculpting, and optimization, providing greater control over the mesh preparation process.
4. Importing the Refined Mesh into CAD Software
The next step is to import the refined mesh file into CAD software equipped with reverse engineering capabilities. Software like Geomagic for Solidworks is a robust option for handling complex and organic shapes, offering advanced surfacing and feature extraction tools. For parts with simpler geometries and predominantly flat surfaces, Xtract3D provides a more streamlined and cost-effective solution.
Once imported, align the scan mesh with the coordinate system in your CAD environment. This often involves rotating and translating the mesh to align with orthographic views, simplifying the subsequent modeling process.
Mesh model imported and aligned within Solidworks, prepared for surface extraction and solid modeling.
Tip: Aligning your scan mesh to the orthographic views (front, top, right) in your CAD software simplifies sketching and feature creation, making the reverse engineering process more intuitive and efficient.
5. Extracting Key Surfaces for Solid Model Creation
Converting a mesh into a solid model involves extracting surfaces and features from the scan data. There are three primary approaches: semi-automatic surfacing, automatic surfacing, and manual redrawing, each suited to different scenarios and design requirements.
Semi-automatic Surfacing: For complex curved surfaces that are challenging to model manually, semi-automatic surfacing is an excellent choice. This method uses algorithms to detect and fit surfaces to regions of the scan mesh. You can adjust the sensitivity of the surface detection to capture varying levels of detail. Software like Geomagic for Solidworks allows you to interactively refine surface regions using a “brush” tool, adding or subtracting areas to precisely define the surfaces. This technique is ideal when you need maximum control over surface accuracy and editability, particularly for complex curves and sharp edges.
Semi-automatic surfacing in Geomagic for Solidworks, fitting precise surfaces to the scanned mesh.
Tip: Geomagic for Solidworks’ surface detection tools allow for iterative refinement. By adjusting sensitivity and using the brush tool, you can precisely capture complex surface details.
The extracted surfaces can then be trimmed, extended, and knit together to create a continuous, editable solid body. Semi-automatic surfacing is favored when precise edge definition and future design modifications are paramount.
The resurfaced solid model derived from semi-automatic surfacing, ready for further CAD operations.
Automatic Surfacing: Automatic surfacing provides a rapid method to generate a solid model directly from a closed, or “watertight,” scan mesh (refer to our guide on STL file repair). While quick, automatic surfacing may sacrifice some accuracy, particularly around sharp edges and intricate details. Once auto-surfaced, you can use standard CAD tools to subtract or add features to the resulting solid body. However, directly manipulating the underlying surface topology can be more challenging compared to models created with semi-automatic surfacing.
Automatic surfacing is well-suited for applications where absolute edge accuracy is less critical, such as creating ergonomic shapes from body scans or generating jigs for modifying handcrafted objects. In these cases, the time savings offered by automatic surfacing outweigh minor deviations in edge fidelity.
Automatic surfacing quickly creates a solid model from the scanned mesh, trading some accuracy for speed.
Note: Comparing automatic and semi-automatic surfacing reveals a trade-off between speed and accuracy. Automatic surfacing is faster but may result in slightly less precise edge representation.
Manual Redrawing: For simpler geometric features like holes, bosses, and pockets, manual redrawing directly in CAD is often the most efficient and accurate approach. Reverse engineering software facilitates this by allowing you to define sketch planes aligned with flat surfaces on the scan mesh. You can also extract cross-sections directly from the mesh to guide your sketching, ensuring accurate replication of the original object’s shape. This method combines the precision of CAD sketching with the reference data from the 3D scan.
6. Integrating the Reverse Engineered Model into New Designs
Once the scanned object is converted into a solid model, it becomes a versatile component for new designs. In our example of the digital gauge jig, the solid model of the air vent component is subtracted from another solid body to create a negative space, precisely forming the jig that will securely hold the original part. Furthermore, the dimensions and curved surfaces extracted from the scan using semi-automatic surfacing are used as references for designing the new gauge component, ensuring perfect integration.
7. 3D Printing the Final Design for Functional Prototypes and Parts
The culmination of the reverse engineering process is 3D printing the newly designed parts. Utilizing a high-resolution stereolithography (SLA) 3D printer like those from Formlabs (Formlabs SLA 3D printers) is crucial for achieving accuracy comparable to the precision of engineering-grade 3D scanners. For jigs and functional parts requiring strength and dimensional stability, Formlabs Rigid 4000 Resin (Rigid 4000 Resin) is an excellent material choice.
High-precision sample part 3D printed in Rigid 4000 Resin on a Formlabs SLA 3D printer.
Sample part
Experience Formlabs Quality Firsthand: Request a Free Sample Part
See and feel the exceptional quality of Formlabs 3D printing. Request a free sample part 3D printed in Rigid 4000 Resin, delivered directly to your office.
Upon completion of these steps, the 3D printed jig is ready to be used for assembling the new digital gauge onto the Volkswagen Golf’s air vent. This demonstrates the power of 3D scanning and 3D printing to create custom solutions and integrate aftermarket components seamlessly.
The completed 3D printed jig, made with Rigid 4000 Resin, ready for assembly.
3D scanning technology enabling precise digital capture for reverse engineering and design.
White Paper
Unlocking Innovation: 3D Scanning and 3D Printing Across Diverse Applications
Explore the broad spectrum of applications for 3D scanning and 3D printing, including replication, restoration, reverse engineering, metrology, and beyond. Download our white paper to delve deeper and discover how to implement these technologies in your projects.
Download the White Paper
Selecting the Right Tools for Your Reverse Engineering Needs
Choosing the appropriate 3D scanner is the initial critical step in any reverse engineering endeavor. To guide you in this selection process, we invite you to explore our white paper, which provides detailed insights into 3D scanners that complement high-accuracy 3D printing. Additionally, our webinar offers further exploration into diverse production applications leveraging these powerful technologies.
Download the White PaperWatch the Webinar Now
