Welcome to the modern era of computer-aided design, where rigidity is a thing of the past, and flexibility dictates the future of engineering and architecture. If you have ever felt entirely bogged down by complex software that demands you plan every single step before you even draw your first line, you are certainly not alone. Enter Direct Modelling in BricsCAD, a fundamentally different, highly intuitive way to approach 3D design that prioritises your creativity over rigid software rules.
For decades, the CAD industry has been dominated by traditional parametric workflows that force designers to manage sprawling, complex history trees. However, as design cycles shorten and the demand for rapid iteration increases, professionals are actively seeking more agile solutions. This is where BricsCAD steps in, offering a unique hybrid environment that blends the best of both worlds.
In this comprehensive guide, we will explore the immense power of 3D modelling BricsCAD has to offer. We will dive deep into its tools, interface, and intelligent features, equipping you with actionable insights to transform your design workflow completely.
To truly appreciate the power of BricsCAD direct modelling, it is crucial to understand the foundational philosophies of modern CAD software. When analysing history-based vs non-parametric CAD, the differences in workflow are stark.
Traditional 3D CAD systems rely heavily on a history tree. In this approach, every sketch, extrusion, fillet, and boolean operation is recorded in a sequential list. If you need to change a foundational sketch, the software must compute the entire history tree from the top down. While this is fantastic for highly structured, predictable families of parts, it becomes a monumental headache when making unexpected, late-stage design changes. A single alteration can cause a cascade of errors, breaking your model entirely.
History independent direct modelling allows you to interact with the current geometry without relying on the order in which features were created. In BricsCAD, this approach can still be parametric. Three dimensional geometric and dimensional constraints can control solids and surfaces without requiring a sequential feature history.
The flexible 3D design workflow benefits of this approach are immense:
Editing 3D solids without history tree restrictions means you simply select a face, edge, or vertex and move it. BricsCAD handles the underlying mathematics, recalculating the geometry on the fly.
There are many software packages on the market, but 3D modelling BricsCAD style provides a distinct advantage. It offers a familiar DWG-based environment, meaning that if you have experience with traditional 2D drafting software, transitioning to BricsCAD 3D tools will feel incredibly natural.
Both AutoCAD and BricsCAD provide solid and surface modelling and history independent direct modelling. AutoCAD’s PRESSPULL command can extrude bounded areas and offset three dimensional solid faces. Its offset behaviour can also modify adjacent faces. BricsCAD’s direct modelling workflow additionally includes DMPUSHPULL, Design Intent Recognition, feature based face selection, deformable modelling, three dimensional constraints and access through the Quad cursor menu.
At the heart of the software are the direct modelling operations. These tools allow you to sculpt and shape your digital prototypes as if you were working with digital clay.
The cornerstone of direct modelling in BricsCAD is the Push/Pull command. Push pull modelling techniques for solids allow you to select any face of a 3D model and simply drag it to add or remove material.
Push/Pull works directly on existing three dimensional faces. BricsCAD’s EXTRUDE command is also not limited to sketch based workflows, since it can extrude closed two dimensional entities, regions, detected boundaries and faces of three dimensional solids.
Direct modelling does not mean sacrificing accuracy. Thanks to dynamic input for 3D modelling, you can achieve pinpoint precision on the fly. When you initiate a Push/Pull or move command, data entry fields appear directly next to your cursor.
Actionable Tip: When using Push/Pull, type the required distance or radius and press Enter. During DMPUSHPULL, press TAB to cycle through parallel reference faces. Press SHIFT and TAB to cycle through them in reverse. In commands that display several dynamic fields, such as line creation or grip editing, TAB moves between the available fields.
BricsCAD can remove recognised protrusion and depression features by using DMSELECT to select all relevant faces and then erasing them. SOLIDEDIT can also delete selected faces and repair the solid, although it cannot remove innate faces. After editing imported geometry, DMAUDIT can be used to check and repair ACIS errors, while DMSIMPLIFY can remove unnecessary edges and vertices and simplify suitable geometry.
One of the most praised innovations in the software is the BricsCAD Quad cursor for 3D editing. Instead of forcing you to hunt through endless ribbons and toolbars, BricsCAD brings the tools directly to your cursor.
The Quad is a highly intelligent, context-sensitive, machine-learning-driven tool palette. How does it work?
Learning how to use BricsCAD manipulator tool is arguably one of the most rewarding steps in mastering the software. The Manipulator is a versatile, visual widget that appears on your selected geometry, allowing for rapid movement, rotation, scaling, and mirroring, all without typing a single command.
When you select an entity and activate the Manipulator, a 3D triad appears.
What truly elevates BricsCAD direct modelling above its competitors is its “Design Intent” engine. When you are editing 3D solids without history tree data, the software needs a way to understand how different parts of the model relate to one another.
During direct modelling operations, BricsCAD can recognise and preserve selected geometric relationships between solid surfaces. Supported relationships include tangent surfaces, coincident planes, parallel planes, perpendicular planes, cylinders perpendicular to planes, coaxial cylindrical or conical surfaces and equal radius cylindrical or spherical surfaces. Equal radius recognition can keep relevant hole radii synchronised, while coaxial recognition preserves a shared axis.
These options are controlled through the Design Intent toolbar or the DMRECOGNIZE setting. They can be enabled individually or switched on and off collectively. BricsCAD V26 does not list a “Recognise Symmetrical” Design Intent option. To change one hole independently, disable the relevant recognised relationship, such as equal radius or coaxial recognition, and review any explicit constraints applied to the geometry.
While direct modelling is phenomenal for rapid ideation, there comes a time in every mechanical design process when strict rules and parameters must be enforced. BricsCAD allows you to effortlessly bridge the gap between direct and parametric design.
You are not forced to choose between one methodology or the other. You can start with freeform direct modelling and subsequently introduce 3D geometric constraints in BricsCAD precisely where they are needed.
For instance, you might decide that two specific faces must always remain parallel, regardless of future edits. By applying a parallel constraint, you lock that design rule into the model. Other available constraints include concentric, perpendicular, tangent, and coincident.
Beyond geometric rules, applying dimensional constraints to solids allows you to create fully parametric, family-driven parts. You can apply a distance constraint between two faces and assign it a mathematical parameter (e.g., “Length = 150mm”).
Parameters can be linked through mathematical expressions. For example, a hole can be kept centred by constraining its position and relating the appropriate offset dimension to half of a controlling length parameter. The behaviour depends on a complete and solvable set of geometric and dimensional constraints. Push/Pull takes active three dimensional constraints into account during the edit.
These tools culminate brilliantly when creating complex 3D assemblies. BricsCAD approaches assemblies with an intuitive, bottom-up or top-down methodology. You can import various separate parts into a master file and use 3D constraints to physically link them together.
BricsCAD Mechanical supports assemblies containing local mechanical blocks, external mechanical blocks, external references and three dimensional solids. The appropriate editing method depends on the component type. Local blocks can be edited in the Block Editor, external components can be opened in their source drawing, and external references can be changed through the reference editing workflow. Direct modelling commands can then be applied within the appropriate editing context, after which referenced assembly information can be updated.
One of the most persistent bottlenecks in modern engineering is collaborating with stakeholders who use different CAD platforms. Communicator for BricsCAD supports formats including STEP and IGES. Depending on the source file and import settings, an assembly can be imported as plain geometry or mapped into native blocks or mechanical components. Imported geometry can also be repaired, stitched and simplified during post processing.
This is where the true genius of direct modelling in BricsCAD shines. Once imported geometry has been translated into valid ACIS solids or surfaces, BricsCAD’s direct modelling operations can be applied without requiring the original model’s feature creation history. The exact import result can vary, so an imported file is not guaranteed to become a single editable solid.
Modifying imported DWG geometry or external solid files is beautifully straightforward:
Need to widen a slot on a motor housing supplied by a vendor? Just grab the internal faces and pull them. To remove a suitable embossed feature, use DMSELECT to select the complete protrusion and then erase it. SOLIDEDIT can repair the solid after suitable faces are deleted, although it cannot remove innate faces. The success and time required depend on the topology and quality of the imported geometry.
The landscape of computer-aided design is evolving, moving away from rigid, punitive systems towards intuitive, designer-first workflows. Direct modelling in BricsCAD encapsulates this shift perfectly, offering an environment where your ideas can flow onto the screen without being hindered by software mechanics.
By mastering direct modelling operations, leveraging the intuitive Quad cursor, and familiarising yourself with the Manipulator, you can drastically reduce your design time. Furthermore, by seamlessly blending explicit modifications with 3D geometric constraints, you achieve the ultimate holy grail of CAD: total flexibility coupled with absolute precision.
Whether you are conceptualising a brand-new product, simplifying complex 3D geometry for manufacturing, or modifying imported files from external vendors, BricsCAD provides a robust, intelligent, and highly responsive toolkit. It is time to stop fighting with history trees and start experiencing the true freedom of direct modelling. Dive into BricsCAD today, and redefine what is possible in your daily design workflow.
Question: How is direct modelling in BricsCAD different from history-based parametric CAD, and when is it better? Short answer: Direct modelling lets you modify the current faces, edges and vertices of three dimensional geometry without relying on a sequential feature history. BricsCAD can preserve supported geometric relationships through Design Intent Recognition, while explicit three dimensional constraints provide stronger parametric control. Direct modelling is especially useful for conceptual changes, imported ACIS geometry and models whose original feature history is unavailable. Constraints can be added where dimensions or relationships must remain controlled.
Question: How do I make precise edits without sketches in BricsCAD? Short answer: Use Push/Pull to move or offset solid faces and enter an exact distance or radius in the dynamic field. During DMPUSHPULL, TAB cycles through available parallel reference faces and SHIFT plus TAB cycles through them in reverse. Other commands may display several dynamic fields, in which case TAB moves between those fields. BricsCAD’s EXTRUDE command can also work with faces, closed profiles, regions and detected boundaries without requiring an associative sketch feature.
Question: What are the Quad cursor and the Manipulator, and how do they speed up 3D editing? Short answer: The Quad is a context-aware, AI-driven cursor palette that surfaces the right commands where you’re pointing, 2D tools over lines, direct modelling tools (Push/Pull, Extrude, Offset) over faces, reducing clicks and mouse travel. The Manipulator is a 3D triad that appears on selected geometry for instant translate/rotate/scale/mirror without typing commands. Drag axes to move, arcs to rotate, hold CTRL while dragging to copy, and reposition the anchor to set a precise base point. Together they keep your focus on the model and accelerate every edit.
Question: Can I mix freeform edits with parametric control and build assemblies in BricsCAD? Short answer: Yes. You can begin with history independent direct modelling and then add three dimensional geometric constraints, dimensional constraints, parameters and expressions. A centred feature requires a complete and solvable constraint arrangement rather than only a single formula. BricsCAD Mechanical supports local and external assembly components, but the editing workflow depends on the component type. Local blocks can be edited in the Block Editor, external components can be opened in their source drawing, and references can be edited through the appropriate reference editing workflow.
Question: How does BricsCAD handle imported “dumb” solids (STEP/IGES/DWG) and preserve design intent? Short answer: Direct modelling commands can be applied to valid imported ACIS solids and surfaces. Design Intent Recognition can preserve supported relationships such as coincident planes, parallel or perpendicular planes, coaxial surfaces and equal radii. Fillets, chamfers, protrusions and depressions can be identified separately through DMSELECT. Face deletion can repair suitable solid geometry, but it is not guaranteed for every face and cannot remove innate faces. Design Intent options are controlled through the Design Intent toolbar or DMRECOGNIZE setting; BricsCAD V26 does not include a “Recognise Symmetrical” option.
