![]() To achieve this quality of render, we need to work around these shortcomings: Single item, Anti-aliased with outline and theme Note, the front panel is not rendered correctly.įor a recent project (a curvy bass-reflex subwoofer) I wanted to make a rendering of each part as neatly as possible, composited into a contact sheet much like a Lego catalogue would show the parts and assemblies. It works fairly well, however the images are not anti-aliased – so they look jagged, they’re yellow by default and may have rendering artefacts. OpenSCAD can output an image in PNG format. ![]() Post-processing output For 3D Renderingsįor 3D renderings, if photorealism isn’t a goal you probably just want clean drawings with smooth edges and shading. Despite having used OpenSCAD for years, I still refer to it when doing something slightly odd. The official cheatsheet is an excellent reference. In addition, working in 2D until 3D is needed helps, see the section earlier in this article. To reduce Z-fighting, which is the result of co-incident (enough) planes, it’s necessary to make objects that would otherwise have co-incident planes translate slightly just apply a translation of 0.001 or so in a direction normal to the planes, taking care to do to this in increments for multiple instances. Includes main.scad and instantiates modules from include/Īssemblies and individual parts for 3d rendering Parts related to the project usable elsewhere. Templates and fixtures to aid manufacturing The main bulk of the project separated into main parts. Reference materials, datasheets, simulations, etcĪny files you’ve released to manufacturing, by revision number Make targets to render everything discussed in this documentĪll build products produced by the makefile in the mirror image of the source go here Includes everything in include/, and defines main parameters For my speaker design and my 2u rack design, I adopted the following convention I think it has helped greatly: File/directory It’s all to easy to end up with a monolithic file with a lot of hardcoded variables and confusing modelling. Large projects can be difficult to manage. Organise larger projects using directories and files The only caveats are the artefacts in the GL based preview, and the rendering time if you’ve used a lot of curves. As a result, it’s not necessary to do potentially complex trigonometry to position the fixtures. This allows the fixtures to be described negatively and in the same frame of reference as the main subtraction. Difference of a difference, note artefacts Here, for a conduit light adapter design, I used a difference of a difference to effectively subtract a space at an angle, complete with mounting fixtures. Sometimes when describing negative space it’s useful to do a difference of a difference. Module rounded_extruded_square ( l, d ) linear_extrude ( 100 ) offset ( - d ) offset ( d ) cube () Īs stress concentrates at sharp changes in geometry, adding a chamfer or fillet can be the difference between an extremely strong part and one that fails straight away. This is often performed manually using a hull between circles, for example: It’s easy, though, to chamfer/fillet extrusions in negative and positive space. There have been user-land solutions however, but with caveats. OpenSCAD can’t currently chamfer or fillet 3D objects. It’s useful to re-use the 2D objects again for things like holes, supports, etc.The offset transformation allows easy rounding, filleting and shelling if combined with separate 3D operations.No z-fighting, so no marginal adjustments to make sure you avoid co-incident planes.In OpenSCAD, if your design can be described as one or more 2D shapes that can be extruded (etc) into a 3D features, it’s much better to start them in 2D first – here’s why: In this section I’ll detail a few hints I’ve thought about when producing a lot of designs for various things around the house. This allows to produce files that can be used for sheet metal cutting, machining and renders – while allowing for complex designs without creating a mess. ![]() I’ve used OpenSCAD 3 to produce a few things that were sent to be manufactured this article shows how I adapt its output capabilities and how I approach a design. 1ĭespite being actively developed, broadly used and powerful 2 there are many shortcomings which make it difficult or sometimes impossible to use outside of 3D printing. It’s popular within the 3D-printing community due to its ability to produce STL files. As it’s script-based, it’s fantastic for parametric design and the files can be version controlled just like a software project. OpenSCAD is an open-source CSG based script-only CAD package.
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