Adding 3d text in Blender
Want to add text to a 3d model in Blender and have it ready to 3d print?
We do a lot of adding text to objects for 3d print. We thought we would share our workflow and hopefully make this something you can easily do yourself. Add text, convert it to a mesh and merge it with another mesh so that you end up with a single solid model that will successfully print on your 3d printer.
Step 1: Load your model and add some text.
<shift+A> to add, then select text.
Step 2: Edit the text.
<tab> enters and exits edit mode for the selected object. Also, check the properties panel on the right of the screen (under the big "F" tab). Changing font would be a good idea. Give the text some depth with the Extrude setting. Make sure the Bevel Depth is zero. Note: The reason for not using a bevel is that Blender creates a lot of intersecting faces at the corners, this would need a lot of manual clean-up later.
Step 3: Convert the text to a mesh
<alt+C> then choose "Mesh from Curve/Meta/Surf/Text".
Step 4: Fix the duplicate vertices Blender always creates during conversion.
Converting text to a mesh results in a non-manifold mesh, removing doubles fixes this and you should then end up with a solid model for the text. With the text selected, <tab> into edit mode and type <A> to select all vertices. Then from the menu Mesh -> Vertices -> Remove Doubles. You can verify that double vertices were removed at the top of the screen.
Step 5: Add crease settings to get nice sharp lettering later in the process.
Still with the text mesh in edit mode, with all vertices selected, add a crease to keep the lettering nice and sharp. <shift+E> and drag the mouse until all the edges turn red.
<tab> to exit edit mode.
Step 6: Move the text mesh so that it intersects the mesh you are adding text to and join them into a single model.
Tip: Before carrying out any Boolean operations, get in the habit of removing or applying any Modifiers beforehand. Applying a boolean will apply any Modifiers automatically. If you had a Subsurf modifier active - that would result in part of your mesh being very dense and others less so. Removing the modifier first keeps you in control of the mesh.
With the text mesh selected, we need to add a modifier (the tab with the wrench icon in the properties panel). Add a Boolean modifier and set it to Union. Set the Object to the model you are adding text to (you can use the eye-dropper to click on it if you are not sure how it is named.)
Tip: If you will be using Blender a lot for 3d printing, seek out the BoolTool add-on for Blender. It will save you a lot of time. It does not come bundled so you will have to search for it and install it separately.
Step 7: Apply on the Boolean modifier.
All going well, you should see the text mesh and the banner mesh merged into a single object.You will find the Apply option in the Properties panel on the right of the screen, under the "wrench icon" tab. When you Apply the Boolean modifier, your original un-altered model is retained, move it out of the way or delete it.
Step 8: Check the model for 3D Printing.
For the final step, checking and exporting the model, you will need to enable an add-on. From the menu File -> User Preferences, select the Add On tab. Search for "3D Print" and "3D Print Toolbox" and check the box to enable it. Once checked, you can close the user preferences.
You should now see a 3D Printing tab in the tool menu on the left of the screen. Press <T> to make the tools visible if not already shown.
This gives you some nice tools to check your model. The main thing to watch out for is "Non-Manifold Edges" which means you either have a hole in your model or some internal geometry that should not be there, and "Bad Contig. Edges", which means some of the faces are likely inverted and pointing into the model instead of facing the outside.
To fix Non Manifold Edges - <tab> into edit mode, the count of Non Manifold Edges becomes a button that will highlight the issues for you. Toggle in and out of wireframe view to see the edges, with <Z>. You will need to fill any holes and remove any internal geometry. Some handy keyboard shortcuts for editing:
<G> moves the selection.
<F> fills a face between selected vertices or edges.
<. on the numpad> Centers your view on the current selection
<spacebar> brings up a searchable list of further commands. Repeat use will bring up the last command. I use this to Merge vertices as a quick way of cleaning up issues.
<delete> Deletes, but also brings up handy options to dissolve edges or vertices.
<K> Knife cut. You can create a new edge between two or more vertices that cuts through faces. I often use this to chop up a face with more than four edges so the Boolean modifier works properly in step 6.
To fix Bad Contig. Edges, in edit mode, select all vertices, then from the menu Mesh -> Normals -> Recalculate Outside. This will often fix the problem but sometimes you have to go looking for the flipped face and flip it manually (using the same menu).
You can treat the other warnings as advisory. Depending on your printing software, these can usually be ignored.
If the Boolean modifier causes some letters to disappear, this is likely due to the code struggling to figure out how the faces intersect ngons (faces with more than four edges). Add a triangulation modifier to your model mesh, this gives the code a better chance of figuring out how to do the join.
Step 9: Add a subsurf modifier if desired to the mesh which will smooth out sharp edges.
Because you added a crease to the text, the text will remain nice and sharp. Leave the subsurf at level 1 so that the exported file is not too big. You can go to Subsurf level 2, but higher than this is a waste of time as you will be exceeding the resolution of your printer.
Step 10. Export your model.
Export the model using the button on the 3D Printing tab on the left edge of your screen. There are a few formats supported. .STL works in almost every circumstance. Before exporting, Select the blue icon to apply the scene scale on export. This means 1 blender unit = 1mm in your STL file. Since STL files do not include any unit of scale information, your printing software will usually ask for confirmation that 1 unit = 1mm when you import it.
That's it. If you made it this far, you should have an STL file you can import into your slicing software and print from.
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