3D printers, also known as 3D rapid-prototypers, are capable of taking digital geometry in the form of a stereolithographic file (.stl) and producing small models. Here at Taubman College we currently have five ABS 3D printers available to students. The necessary file can be produced from a variety of different 3D modeling software, such as Rhino, 3D studio max, and Digital Project. Regardless of what software one is using, the file must be “watertight,” meaning no open edges.
All 3D Print Lab assistants are available for consultation and walk up file preparation/execution during their posted shifts.
The College currently has five ABS printers, which operate in the same manner, but have different build volumes. The uPrint SE Plus build volume is 8″x8″x6″ – while the Stratasys 170s have a build volume of 10″x10″x10″. Models with a wall/column thickness less than 0.04″ or 1 mm are printed at the student’s own risk and expense. Print times can range from 1 hour up to 24 hours. After the print is complete, the structural support is removed by placing it in a chemical bath for around 12 hours.
One of the more difficult tasks when it comes to 3D printing is creating a clean file. While the methods described below will aid in creating a printable model, sometimes a file is too complex to be printable. If you are unable to successfully create a file, contact a lab assistant for further help. They may be able to correct the file, but please note that this is not always the case. Sometimes the only way to make a file printable is to recreate it altogether.
Note: These following methods primarily apply to the 3D modeling software Rhino.
Checking Nurbs File
If you have a polysurface in Rhino and you would like to know if it can be printed there are a few things that can be done to check this. First, before converting the file to a mesh (STL file), check to see if the file is a closed polysurface or an open polysurface. If it is an open polysurface, your geometry is not “watertight”. The simplest way to check to make sure it is a closed polysurface is to bring up the properties dialog box (F3). If the polysurface is closed, then proceed to export it as an .stl (mesh). This will approximate the cost of the print, but will not account for support material which will be needed.
Trouble Creating a Solid
If you find that your object is not a closed polysurface, there are many different ways to proceed. It is best to fix the geometry, rather than converting it to a mesh and trying to repair it. For further information on how to make a closed, solid model visit this link.
Exporting to STL
Once you have a closed polysurface, the next step is to export the geometry as an STL file. Select the geometry you wish to export and go to “File”, “Export Selected.” Select “Stereolithography (.stl) and click “save.” A new dialog box should appear. Usually the default is sufficient, but if you wish to adjust the tolerance of the object (number of polygons) it can be done here. Select “Ok.” A new dialog box appears. You don’t need to change anything here, binary is fine, just hit “Ok.”
Checking STL Mesh
Once you have created an stl file, even if the original geometry was a closed polysurface, it is a good idea to verify that the mesh is a good mesh. To do this open the STL file, select the geometry and type in “CheckMesh.” It should read, “This is a Good Mesh” at the top and contain no naked edges or degenerative faces. If this is the case, your file should be suitable for 3D printing. If you are having trouble resolving any issues with the polysurface or mesh, a lab assistant can try repairing the mesh in the 3D Print Lab.
1. Have an Idea
The first step is to have an idea in mind of what you would like to produce. How large does it need to be? How thin are the members? What does the geometry look like? All 3D Print Lab Assistants are available for consultation and walk up file preparation/execution during their posted shifts (see calendar above). We highly recommend meeting with a 3D Print LA first if you have never submitted a 3D print request.
2. Become Familiar with Equipment
It is important to have a basic understanding of the equipment. This will be helpful with file creation, printing feasibility, and determining approximate cost. Reading the overview of the equipment above is a good start. Additionally, if this is your first 3D print, it would be a good idea to talk with a 3D print LA to see how the equipment works as well as view sample prints in the lab. It is best to do this early on so as not to spend a lot of time working on a file, only to find out that it can’t be printed. A 3D print LA can be contacted via email at firstname.lastname@example.org. Once a schedule is set for the semester, it will be posted in the calendar above and on the door of the 3D Print Lab.
3. Create the File
Often times the most challenging part of the 3D printing process is creating the actual file. If the file is not “watertight” when submitted, there is a good chance it won’t be able to be printed. The 3D Print LAs may be capable of repairing an erroneous STL mesh, but it is in your best interest to submit a clean file from the start, otherwise you risk delaying the process. While there are many different 3D modeling softwares capable of producing a STL file, Rhino is the most prevalent within the College, and therefore is the software that is addressed. For help preparing and verifying a file for 3D printing please see the file preparation section.
4. Submitting the File
You MUST be logged onto your University of Michigan domain (email@example.com) in order to access the form, you cannot use an alternative email domain.
In order to submit a STL file to print, carefully fill out this 3D print submission form with all the important information. You may only submit one STL file per form with a maximum size of 100MB – there should be no reason for a file to be any larger. The file should only include the items you need printed, DO NOT send working files with multiple iterations or hidden geometries. Please nest ALL parts of your geometry within the X,Y,Z volume limits. The closer you nest your individual pieces next to others the cheaper and faster the print will be. If you have multiple large prints which need multiple trays, please submit a separate form for each of those prints. If you have questions about your STL file, please visit the 3D Print Lab during a 3D Print LA shift to discuss the file before you submit the form.
5. Edits to the 3D Print Submission Form and/or STL file
You will automatically receive an email receipt of your 3D Print Submission Form responses and you will be able to make edits to the responses then resubmit. However you will NOT be able to upload a new version of the STL file. You would have to submit a new 3D print submission form. Therefore, please be sure to submit the correct file the first time. A 3D Print LA will reach out to you via email if there are any issues with your file, and in that case you may communicate via email with an updated STL file or visit the 3D Print Lab with an updated STL file on a USB drive. If you do submit another 3D Print Submission Form with an updated STL file, please use the “Notes” section of the form to communicate this.
6. Pay for the 3D Print at the Media Center
Once you receive an email that your 3D print is finished, pick up the 3D Print Order Form from the 3D Print Lab, which the 3D Print Lab Assistant will fill out, and pay for it at the Media Center. Place the paid receipt in the mailbox outside the FABLab Office (room 1225) prior to removing your 3D print from the 3D Print Lab.
7. Take your 3D Print
A 3D print LA can be contacted via email at firstname.lastname@example.org.