Start FreeCAD, and follow the earlier instructions to get into the Sketch Editor in the Part Design Workbench. Like riding a bicycle, with luck CAD will suddenly make sense. As always, best to start simple and work up. The software looks and can be intimidating. Sadly, these advantages aren’t handed to the user on a plate. In the event the model is changed, it often unnecessary to rework the outputs asking a computer to generate a complete set of new 2D drawings is much easier than asking Mr Grumpy to start again! Many human errors are eliminated because the outputs are produced automatically direct from the solid model. Stamping, grinding, engraving, laser cutting, etching and other manufacturing processes might be available too. Or the G-code needed to make the object by cutting in a lathe or milling machine. Another common output is the G-code instructions needed to create the real object with a 3D printer, usually plastic but concrete and metal are also possible. Yet another representation is a mesh for stress/strain analysis. Another output is photo-realistic views of the object, in metal, with or without paint. For a manual workshop, the 3D model can be rendered as 2D drawings in First or Third Angle. Seeing the model on-screen in 3D makes it much easier to spot mistakes.ģD CAD offers various ways of converting the model into a real object. Think ‘modelling’ instead of drawing, albeit the solid model only exists inside a computer. Although ‘Sketching’ is part of the process, it might help beginners to dump the idea that 3D CAD is drawing at all. It works by developing solid models, not views. Much opportunity for confusion.ģD CAD eliminates many 2D drawing errors, and, once mastered, the process is generally quicker. Most modern drawings are Third Angle, older European drawings are usually First Angle, and amateur drawings can mix both in the same plan or be neither. Mixing up the difference between First Angle and Third Angle can be desperate because the made object could be a mirror image of that intended. It helps if both understand and follow the same conventions and neither blunders during translation. Secondly it’s necessary for the user to translate the group back into a 3D object. First it’s necessary for the draughtsman to mentally translate a 3D object correctly and unambiguously into groups of 2D views. Two major problems with 2-Dimensional technical drawings. Nonetheless, I believe it’s clear enough to be used by someone else to make a tool-post key. As an amateur I claim the example above to be a ‘First Angle’ Drawing, but I might be wrong! Also, trained draughtsmen may not be impressed by my treatment of dimensions, line thickness or labelling. Proper technical drawings are skilled work. With practice it’s faster than rule and pencil, and far neater, especially after multiple mistakes are corrected with a grubby rubber!īehind the scenes 2D can be messy! Here's with construction lines: These can be done by hand on a drawing board, but I prefer a computer. However, sketches like these are a good way to prepare for a 3D CAD model.įor more complicated objects or drawings other people will work from, I do ‘proper’ technical drawings. It’s a memory aid rather than a technical drawing. A rough drawing capturing the shape and dimensions needed to make the item is good enough. It’s the key used on my lathe’s 4-way tool-post.įor objects this simple, I’d do a ‘back of an envelope’ sketch. I’m not competing with the Alibre thread! The idea is to get people started by demonstrating how straightforward it can be to 3D model simple objects without plunging into shark-infested depths. The ‘starter’ piece got some positive feedback and a PM conversation about finding up-to-date FreeCAD Tutorials with Thor inspired me to show what happens once FreeCAD is ready to go. I find it handy for simple work, and as a safety-net in the event Fusion360 becomes unaffordium. FreeCAD is of interest because it’s Open-Source free, not because it’s the best possible CAD choice. As getting started with 3D-CAD is a problem I recently outlined how to get FreeCAD into a position where a beginner could start modelling.
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