How to cut STL models for 3D printing in Meshmixer


It’s obvious that models bigger than the print volume cannot be printed as one piece Basic cuts along the Z-axis can be done directly and Slic3r The solution is pretty straightforward Just specify the height at which the model will be cut You can also choose to rotate the bottom part upside down After the cut the newly created model will be automatically placed on the virtual print surface However, creating complex cuts in Slic3r can be challenging as it’s only possible to define the Z height of the plane cut This may result in unwanted pieces of the model being cut off We can demonstrate this problem by trying to cut one of Hulk’s hands Slic3r uses an infinite plane so even though the hand did get successfully cut So did some other pieces, his leg and the stand Meshmixer is a great tool for cutting models into smaller pieces Let’s start with a simple plane cut Select Edit – Plain cut Hold down the left mouse button to define a plane Change the cut type to Slice so that no part of the model is discarded and confirm by hitting the Accept button The model will still appear as one piece select Edit – Separate Shells to create individual models Another option is to use the Select tool and specify a smaller area of the model to be affected by the cut When we apply the plane cut everything outside of the selection will stay as one piece Despite the plane i ntersecting the geometry as you can see in the lower part of Hulk’s body Again, we have to use the Separate Shells function, otherwise the model will still appear as one piece Let’s talk about aligning pins Adding them will make it a lot easier to glue the finished parts together First open the Objects browser and hide one part of the model created by the cut Next up open the Meshmix menu and drag a primitive, a cylinder in our case, to the plane created by the cut A gizmo with an arrow and a sphere will appear You can scale the primitive by dragging the arrow and you can reposition it by dragging the sphere Switch the composition mode to Create New Object And when you’re happy with the placement of the primitive confirm with the Accept button We’re gonna have to duplicate the model two times so that we’ll end up with three copies of the primitive Hide the two new copies in the objects browser Next, click on Hulk’s body and while holding down the Shift key click on the primitive a A new menu with the boolean difference option will pop up Untick Auto-Reduce Result, tick Use Intersection Curves and decrease Target Edge Scale Meshmixer will show live preview of these changes When you click on Accept the primitive will create a hole in the model Now we just have to repeat the same process with the other half of the model The Boolean difference consumes a copy of the primitive everytime we use it That’s why we made the two copies This way, we’ll still end up with one copy of the primitive left for export Okay, we’re done cutting. Now let’s just export each of the models as STL As you can see, because we added the aligning pins The parts hold together even without any glue And Hulk… Smash!

Leave a Reply

Your email address will not be published. Required fields are marked *