IDeATe 3D Printing Guide¶
The IDeATe fabrication facility includes a Mosaic Array 3D printing system which we will use for this course. This is a highly useful tool for fabricating complex 3D forms in plastic. The system uses a fused deposition modeling (FDM) process which extrudes a thin bead of melted plastic layer by layer.
The best feature is the design freedom to create complex shapes, including forms impossible with conventional machine shop tools. Of course, using this freedom requires sophisticated 3D CAD skills. The chief limitatation is the speed: many parts take hours to fabricate. The parts are also not solid which can limit the options for modifying parts during post-processing.
In general, I encourage designing most project parts for the laser cutter, since the fast turnaround time and the relative ease of hand modification speeds design iteration and project development. But some design problems will be best solved using 3D printing.
Procedures¶
Design your part as a 3D solid model. Please refer to the design guide below for hints on tolerancing and process limitations.
Export as a binary STL file with millimeter units. STL is the common interchange format for 3D printing. Please note that the file format does not intrinsically specify dimensional units, so I recommend always using millimeters. The STL format describes the part as a triangulated surface mesh, so smooth curves will be tessellated and unwanted subtle edges may be visible in the part. You may choose to adjust the export options to increase the polygon resolution as needed.
You will be given a URL to create a submission which is specific to the class and assignment. Please log into the linked page with your Andrew ID. It will then email you a unique submission link, and you can close the creation page.
Please open the emailed submission link and log in with your Andrew ID. You will see a workspace including a 3D model view.
Please select Add models to upload one or more single-material STL files.
You will need to orient and place your models on the bed, making sure the correct bottom face is flat. Some useful tools for this under the “More” ellipsis are Lay face to bed and Auto-arrange.
You may also open the Settings panel and disable support generation if desired.
Once configured, please select Slice to generate the fabrication plan.
The plan can be previewed using the 3D windows and the two rollback sliders on the right. One rolls back layers, the other time.
You may any add additional notes for the reviewer if needed.
Once the part is sliced to your satisfaction, please select Submit to send the part for review.
A staff or faculty reviewer will check your part for relevance and fabrication and either send it back for correction or forward it for printing. Please note this isn’t a functional or design review, just a check on reasonable resource usage.
3D Printing Design Rules¶
Maximum build volume: 350 mm cube.
Default layer height: 0.2 mm.
As a rule, holes tend to be undersize. Specific recommended adjustments are TBD.
3D Printing Best Practices¶
Keep overhanging features to within 45 degrees of vertical.
Keep fully horizontal overhangs to just a few millimeters length, e.g. the top of a small hole.
Some amount of post-processing is possible, e.g. filing edges or drilling out slightly undersized holes, but the final parts are not solid plastic so the options are more limited than with laser-cut parts.
Submission Problems¶
The most common submission problem is using an outdated link to create the submission; please always check you are using the correct link for the current assignment.
The slicer software only accepts STL files.