MeshMixer is a free open source software from AutoDesk. It’s one of the leading programs to edit and prepare mesh files like .stl and .obj. MeshMixer offers a large variety of different tools to prepare and improve 3D object for 3D printing.
Here is a list of the best tools MeshMixer offers to improve the quality of your 3D prints. Click on them to jump to a part of this Meshmixer tutorial on how to use the specific tool:
First of all, you will need to download and install Autodesk MeshMixer. Next, you’ll need to import the 3D model file you want to optimize: Start MeshMixer and click on Import in the middle of the window.
Next, select the file you want to edit. Autodesk MeshMixer supports the common mesh file types: .STL, .OBJ, .PLY, .AMF and also .3MF, .OFF and .MIX. You can also simply drag and drop files out of the Explorer into the edit space. You can choose between the option to replace the current object or append to the model.
When using MeshMixer, you can either choose your 3D printer from a list or, if not listed, enter the 3D printer properties manually. You can also disable the Printer Bed by clicking on View and uncheck Show Printer Bed. If you own a 3D printer or plan on 3D printing your object, you can choose your type of 3D printer in the top right corner. If your desired 3D printer is not listed or you built your own 3D printer, you can easily add your personal configuration.
When you get lost, you can click on View>Recenter View to focus on the center of the coordinate system again. If you are limited with your mouse, you can hold down the space bar to access all camera tools. When holding down the space bar, you can also change the visual style of your object. MeshMixer can smoothen the surface of your object or show all the triangles your object is composed of.
Click the Edit button on the left and select Transform. Here you can change basic placement data of the object or move and rotate it manually.
When placing objects you can switch between two reference points. First, you have the World Frame which is defined by the center of the coordinate system in your build space. Every transformation or rotation will be in relation to the center. Secondly, you can work with the Local Frame. Here the translation is still relative to the center of the coordinate system. However, the rotation is now defined by the coordinate system of the object you are currently working with. You can also scale your object alongside the X-, Y- and Z-Axis. Switch between both frames via the Transform menu or the bubbles on the Transform circle. Use these basic steps to move and scale your selected object.
By using the Align tool, you can place a flat side your object perfectly onto the build plate. Select the object you want to align and set Base Point as source. Now set “Destination” to the axis of the world coordinate system you want to align. You can flip your object by clicking the blue arrow.
Use the Plane Cut command to create a flat surface. This is a fast tool for creating a smooth and stable surface to print on. Like the transform tool you can move the plane in relation to world or local frame. Rotate and move the plane to the position. The blue arrow indicates the direction you are going to cut. Click on the blue arrow to switch directions.
Before 3D printing your model, you want to make sure, there are no unwanted holes or cuts in the object. You can simply check for irregularities with the repair feature. Click on Analysis>Inspector. After computing, you will see different colored balls pointing towards holes and gaps. The color of the ball symbolizes the severity of the hole. Blue indicates a minor error, which can easily be patched. Red stands for larger holes. MeshMixer will still fix them, but you might want to check these areas after repairing. Pink indicates an island which will be removed in the first step of repairing. You will have to run the Inspector tool a second time to fix the hole for good. You can either click on the balls to fix each error individually or hit Auto Repair All.
It is now time to turn the mesh into a solid.
Sometimes when 3D printing big models with a big volume, you might want to save time and material. This step will show you how to hollow your object.
When you have hollowed your 3D object, it is not yet ready for 3D printing! Some 3D printing technologies like metal sintering use metal dust as material. With SLS printing you only need the shell of your model in most of the times, so it is great to hollow it. However, the powder material inside your model will still be your part of the bargain and will cost you a lot of money if it cannot be removed. If you are planning on sintering your model, you will need to create escape holes for the dust. Luckily MeshMixer offers an effective tool to create custom escape holes! 3D Printing services offer detailed information on minimum wall thickness and size of escape holes.
Execute the hollow command and set Holes per Hollow to 2. When 3D printing larger models you can also add more, but two is sufficient to remove all the dust from the inside. Now set the hole radius and if needed you can add a slight angle to the hole with the taper option. Click on Generate Holes when you have entered the desired settings. You can now reposition the holes by dragging the red dot. You can update the parameters by clicking on Generate Holes again and remove the holes by clicking on Remove All Holes.
Before 3D printing, you want to make sure your object is aligned with the ground plane. To check if your model is planar to the ground plane go to Analysis > Stability. This Meshmixer tool will calculate the Surface Area and Volume of your object. Furthermore, it will show you in red the contact area with the ground plane and if your object can tip. By adjusting the Contact Tol you give or take some clearance between the ground plane and the object. The red dot in the middle of your object indicates an unstable position. Green-lit, it’s a stable one. There is one trick to adjust your object perfectly to the ground plane without transforming in small steps.
Sometimes you want to do a fast analysis of your 3D objects geometry. MeshMixer can not quite compete with industrial FEM-Analysis programs but does a great job in computing properties like volume surface area and mass. The Stability Tool of Meshmixer will calculate these properties for you. Learn how to check the stability of your object with Meshmixer by reading tip 10.
Analyze the Thickness of your model with Analysis > Thickness. You can now set the minimum thickness to the printing service or your own requirements and MeshMixer will highlight the thin areas. When you click on the Balls indicating thin spots, it will select the area and you can edit the area.
MeshMixer analyses the wall thickness by shooting rays from each vertex through the object and measures the closest intersection of rays. You can adjust The number of rays with cone sample. You will get a higher accuracy but it will also take longer to calculate. Cone angle sets the angle between the rays from one vertex. If you want to analyze a wall in every direction and if your object is built out of big mesh tiles, set this angle to high. If you are just interested in the overall wall thickness you can let them on Default. Grazing Angle is the threshold for intersecting rays to define the maximum detection angle. Again, if you are working with a low poly mesh it is best to use a high angle.
MeshMixer offers the great tool to create your own supports. It can also generate supports automatically. Do not generate supports when you plan on printing your model with a 3D Printing service!
Now your 3D model is optimized and ready for 3D printing! You can now export your object by clicking on Export. If you own a listed 3D printer, you can send it directly to the 3D printer’s original slicing program by pressing Print. You can also export the file and open it in the slicing program of your choice. Autodesk MeshMixer also has the option to directly send the model three online 3D printing services: Sculpteo, i.materialise and Shapeways.
Congratulations! You have finished this MeshMixer tutorial.