Download it hereCura is a freely-available program for slicing models to G-Code format. It’s optimised for the Ultimaker 3D printer, but it works fine with any printer based on the RepRap model – and that includes just about all the ones that squirt molten plastic. Cura is available for Windows, Mac and Linux.
Cura is much faster at slicing than most other programs, and the latest version provides both a handy set of tools to visualize your printable object and a dual-user mode – Quickprint, which offers preset options suitable for most everyday print jobs, and Full setting, which gives you the chance to tinker. We’ll look at the full settings in another tutorial.
The first time you open Cura, you’ll see the First time run wizard. This takes you through the process of setting Cura up for your printer, and makes sure your firmware is up to date.
Even if you’re the sort of person who wants to get straight on with playing, it’s worth taking the time to go through the few short setup steps, to guarantee that Cura will give you the best slicing results.
At the end, there’s an optional procedure to check that your bed is level. You can do this manually by moving the hot end to each corner and sliding a piece of paper underneath it, but you may as well let Cura move the print head for you so you know it’s done right. Once the procedure has been run, it will then print a test piece to make sure the bed is perfectly level.
2. Set your preferences
This step isn’t essential, but it’s rather useful to know how much a model is going to cost you. Go to File > Preferences and, in the Filament Settings section, you can set the cost per kilogram (or per metre, if that’s how you buy your filament).
There’s also an option here to Save profile on slice, and it’s worth checking: that way, the settings for each model will be stored so you can compare them later:
3. Load your model
Click the Load model button at the bottom and choose the object you want to load. Cura works with files in STL format, so if your 3D program exports only OBJ files you’ll need to convert them first. Here, we’ve loaded a hand made in Poser. Because it’s hard to control Poser’s scale settings, it’s come in far too large for the machine:
4. Size and position
You can use Cura’s tools to move, flip, rotate and scale the model, using the buttons beneath the preview. On the left are the X, Y and Z mirrors, to flip the model around the print bed; next to that are buttons to rotate the model along the XZ axis, and along the YZ axis. These buttons are enough to orient the model exactly as you wish.
Next come the scale buttons. Use the first to reset the model to its original size, and the second to size it to the maximum the printer can handle. Between these is a text box where you can size the model as you wish. Here, we’ve sized it to 0.2 times its original proportions.
The final button is to reset the model rotation; you can either type an angle in the number field, or drag the black arrow in the preview window, to make the model face in any direction you choose:
5. Check your settings
On the left are the settings you choose in Quick Print mode. There are three quality settings, as well as an option for a thin-walled object. You can also decide whether you’re printing with PLA or ABS, as this affects the printing temperature. And, as best practice, you should measure your filament diameter with a digital micrometer, so you can tell Cura its exact size.
On the top are buttons for changing the object view. Drag in the window to rotate the view, and use the right mouse button (one-button Mac users: hold Ctrl) to zoom in and out. The last set of buttons shows the preview as a solid object, hollow, or as an x-ray view. To the left is the Overhang button, which highlights areas that might be problematic to print. Here, for instance, it’s picked up on the undersides of three of the fingers – but it’s not serious enough to worry about:
6. Start slicing
You’re now all ready to go. Hit the Prepare Print button at the bottom of the window, and wait a couple of minutes while Cura does its job. The time taken to slice the model depends on the size of the model, and also on the number of layers – the finer the print quality, the more layers there will be.
Once the slicing is finished, you’ll see the path for the bottom layer in the preview window. This is colour coded: for instance, the blue line shows the path the print head will take from its starting position to drawing the skirt.
At the bottom of the window you’ll now see an extra panel, showing the amount of filament needed, the estimated print time in hours and minutes, and the cost of the model – based on the pricing info you specified:
7. Ready to go
With the G-Code file now finished, you can either open its location on your computer, copy it directly to an SD card, or print directly to your printer, using the buttons at the bottom of the window.
If you like, you can also view the result layer by layer. Click on one of the group of three similar-looking buttons at the top of the window to turn on X-ray view, as seen here (pop-ups as you hover over the buttons tell you which is which). In the empty text field, type the number of the layer you want to examine, or press the up/down buttons to scroll through the layers one by one:
Cura is constantly under redevelopment, and it’s one of the slickest and most effective slicing solutions there is. In a future tutorial, we’ll look at how to use the advanced settings to customise your print more precisely.