CAN I PREPARE A MODEL FOR 3D PRINT IN ZBRUSH?
Dave Heath, Twitter
Zbrush is one of the best programs to get your 3D models ready for 3D printing. There are a wide range of tools built in that make it so easy to prepare the model. For scaling there is a dedicated 3D Print Hub in the Zplugin menu, but you can still sometimes be left with complicated scaling issues. The best method I’ve found over the years is to have a scaled cube that is either 1cm, 10cm or even a metre. You can get a scaled cube from almost any 3D package and I like to use a CAD package like Fusion 360. You only need to do this once and those cubes will do you for the rest of your time using Zbrush. Test them in your slicing software (Chitubox for example) and make sure that the scaling is all correct. Import them into Zbrush and you will always have a scaled reference to call at any time for any model. If you use a 10cm cube when you draw out the transpose line, you will find that the ticks along the line are split into increments of 10, giving you a scale ruler. This is really useful as you build intricate models, and you can drag that line to different points on your model to check dimensions.
Another great tool that I always use is the Live Boolean tool. If you import any model into the scene (a cube for example) as a new subtool below your model, you can then switch it to a Boolean object using the two little spheres in the subtool panel. Switch on Live Boolean at the top left of the interface and the result will be shown in the document window. You can then slide the cutting-model up and down, left and right and even scale it and see the result of the Boolean live. This really helps when you want flat surfaces on the back of a model or to fit two pieces together. It also helps to see if there are any air pockets or problem geometry inside the mesh.
There are a few more things that will really assist you, such as Decimation Master to lower your polygon count without sacrificing quality. There’s also Check-mesh and Fix-mesh, which asks Zbrush to check and fix any stray vertices (points) or bad geometry.