Over the last four months, I have spent a lot of time working through how to make things that move, and how to produce them in a predictable way in any well-equipped makerspace. I’m defining a well-equipped space as one with a laser-cutter and a 3D printer that handles PLA, though a lathe and mill are nice to have.
Procedural Generation - OpenSCAD
OpenSCAD is a FLOSS project out of Kitchener/Waterloo in Canada. It is amazing and a very good solution if you are comfortable programming. It runs on donations, and it is absolutely the best for things like, ie: furniture design.
* Probably the most interesting for designing things like bookshelves and non-fancy-curved CAD things * you change a single variable and everything else changes * good for modelling plywood, angle brackets, large-scale non-fiddly things * sending out a model is as simple as sending out some code * use GitHub/etc to store your models * Generators exist for doing, ie: 3D printed helical gears. Amazing!
* getting 3D printed helical gears right on it will take years from your life, if you're not good at that already * when you get right into it, this involves a lot of programming effort * if you're only middle-comfortable with programming, will be slower than other packages to get what you want. * this is not a CAM package, there's no machine tooling in here.
Rhino/Grasshopper for OSX
Rhino is great and easy to use. Grasshopper allows linked updates for generated models. In practical terms, that means that a model will update when you change something in the underlying design. While Grasshopper for OSX is in early beta right now, Rhino is still a great, practical choice. It’s pretty affordable, too, at $495USD and a 90-day free trial.
- offline working space available
- Great workspace, good rendering, joints and animations
- Grasshopper is now available on mac in deep beta.
- UI less polished than some low-level Autodesk project
- Maybe overkill if you’re just getting started
Autodesk is the big goon of the OSX CAD world. They have a real sweet spot going on in their acqui-hire policy for smaller companies, which has allowed them to take on a lot with their 123D line of products.
TinkerCAD is Autodesk’s entry-level free-to-play cloud-based CAD offering. It is essentially a toy, best used with a MakerBot or Ultimaker to print action-figure-y non-moving components.
The big pitch for TinkerCAD is that it comes with a lot of pre-modelled drag-and-drop components that will get you started quick, including some fiddly joints that are nice for putting together snap-together pieces. It is a toy and has no measurement tools! I expect you will move on quickly, there are a lot of constraints here.
This is the tool I use most often to design small solid parts for 3D printing.
- Most intuitive modelling controls, relative to other packages
- Exports STL and OBJ files directly
- Can in theory import SVG as sketches to make objects
- easy to save files locally
- do not have to be online to use
- sketches have constraints/suggestions, making them v. easy to handle.
- Designed to manage small, 3d-printed parts, so if you’re doing something complex it will run slowly even on high-end hardware
- Anything to do with curves, lofting, or path-tracing can be very frustrating very fast
- can’t generate one component and linked-edit that component, which means a lot of redrawing parts if you change something.
- gonna have to hand-animate your joints, and they’re gonna be an estimate.
- Do one part at a time
- make sure to draw it out in advance
- do you really need to 3D print that?
Fusion 360 is Autodesk’s challenger to Solidworks, and elect replacement for Inventor. You can get a free/hobbyist licence for 360 for one year by signing up as a hobbyist and tinkerer. Fusion in theory does it all: CAD, CAM, hingeing, and animations. In practice, it has a ton of weirdly awkward little gotchas, like being an always-on cloud computing platform. It might get better, as it is in active development.
- joints, hinges, animations included
- can do large, complex projects
- In theory, modelling is easy!
- things like gear generation scripts exist for the platform, handy!
- CAM toolpath exports, the whole thing, you can run a shop off this
- you are probably using a laptop, and it will probably pig out your resources
- Cloud-based = Do u have internet? No? No work for you!
- You have to place holes as components, rather than dropping a fastener in place and auto-generating around that fastener.
- Super weird, Autodesk-specific control panels and UI conventions
- Component management, etc, shows signs of being inherited from a different world of design than 123D. Long learning curve.
There’s a lot more to be said on this topic, and the next post you should read is about generators, which are LIKE CAD software… but for making things in a generic way that you can then customize using 2D vector drawing software. Here is that post
This post is derived from a talk I did at ITP Camp 2016