Measuring distances in ZBrush

ZBrush was not made with 3D printing in mind. It wasn't even originally made with 3D modeling in mind. For this reason, ZBrush's unit and measurement systems are not well-equipped to handle the task of making things with precise real-world scale. However, since real-world scale is paramount to 3D printing. We need to find a way to make Z-resh measure things accurately and consistently for us. Let's take a closer look at some measurement challenges and solutions.

So we've got a model and we want to measure how big it actually is. Now for this we can use any of the transpose tools. These are the move, scale, and rotate. You can just click on any one of these, or hit W, E, or R on your keyboard. And you'll get this manipulator and you can click and drag this out any way you want. But I want to, put this from top to bottom. And this is going to snap onto whatever part of the model we click on. So if we rotate around you can see it snapped to where we touched here and here. You can make sure it comes out in a straight line, if you hold down Shift.

And it's just going to come straight down. You can also reposition this after you draw it out by clicking and dragging on any of the outer orange circles. Okay, so with this positioned, what we can see is up here in our status bar. This is about two and a half inches long. So what is a unit? It's pretty arbitrary. it doesn't relate to any particular real world unit. So let's try to make this measurement mean something more concrete. Let's go up to preferences and open up transpose units and what I like to do is click on set units and type in something here.

Now you could type in centimeters inches, furlongs it doesn't really matter. And hit Enter. Okay, so now you can see it says 2.5 and something centimeters. The big thing to understand here is what we just typed in is only a reminder for us what the units should be. It does not tell z rush what the unit actually means. Z brush doesn't understand what a millimeter, an inch or a furlong is. This is just for our reference.

Now, one other thing you can do to make the ruler a bit more useful, is to change it's ticks. The ticks are the little dashes along the length of the ruler. And we can actually zoom in here, maybe see them a little bit more clearly. So, let's go up to preferences, and under transpose units, let's go into the minor and major ticks. So what I want to do, is change the major ticks to 10. Let's drag this out, and then set the minor ticks to 100.

So we might even need to zoom in a little bit more before we can see both of them. But with this set to 10 major and 100 minor tics. And also our units set to centimeters. This means that each big tic represents a millimeter. And each small tick represents a tenth of a millimeter. Now, this can help us measure because sometimes tolerances in 3D printing come down to the scale, like a tenth of a millimeter can make a difference between prints coming out well or not so well.

Alright, let's go ahead and zoom back out. I'm going to hit F. So the transpose manipulator is going to be one of your best friends or 3D printing. It's funny because as a tool it was meant to move, rotate and scale objects but now we can use it as a ruler.