3D Printing and Logo Guide

ProtoLab Schedule

All standard 3D Prints must be submitted, approved, and printed through ProtoLab unless given special permission by a ProtoLab TA, the Prototyping Committee, or a professor.

• Monday: 2 PM to 6 PM
• Tuesday through Friday: 12 PM to 6 PM

Mandatory 3D Printing for all SLDPs

All SLDP groups will be required to design and 3D print a one-color logo. All specifications outlined in the Logo specification section must be met. All SLDP groups may design and print a two-color logo to meet the mandatory 3D printing requirement and will receive extra credit for using two colors. Deadlines for this mandatory print are outlined in the deadlines section below and can be found under each individual SLDP page.

Groups must submit an STL file of a logo through the 3D Printing Submission portal by Benchmark A, receive approval from a ProtoLab TA by Benchmark B, and have it printed by Commissioning. The printed logo is a requirement for commissioning, and failure to do so will result in point penalties on the project grade. Prints made not within ProtoLab will not be accepted unless under special circumstances.

Mandatory Manufacturing for all RAD Projects

All RAD groups will be required to implement one manufacturing method in the creation of their prototype. Manufacturing methods include 3D Printing, Laser Cutting, CNC Milling, Advanced Printers, Sewing, and Wood Working. For all methods, training with the MakerSpace is required, go to their training website for the associated instructions to receive training for the desired method.

For 3D Printing, requests must be submitted through the ProtoLab and must follow the specifications outlined for VEX Parts in the “3D Printing & Extra Credit Specifications” further below. For Advanced Printers, requests must be submitted through the MakerSpace/EG1004 Advanced Prints Form on the EG Website.

3D Printing Extra Credit

For HIR projects, students can 3D print one floor plan as a part of this extra credit. Printing the exterior of the building does not count towards this extra credit, but instead, is a project-specific extra credit. Submit an .STL file of the stack-able floors through the 3D Printing Submission portal and receive approval from a ProtoLab TA to get it printed before Commissioning. The exterior of the building must also be submitted as a zip folder with a .STL file and .3MF file through the 3D Printing Submission portal and receive approval from a ProtoLab TA to get it printed before Commissioning.

For VEX projects (MRR and LAZ), a robot part that will help their robot complete the course can also be designed. Robot parts can only be one color. Submit a zip folder with a .STL file and .3MF file of the VEX part through the 3D Printing Submission portal and receive approval from a ProtoLab TA to get it printed before Commissioning.

For RAD projects, there are no printing extra credit opportunities outside of project-specific extra credit. Mentor assigned extra credit tasks relating to printing are allowed only if it is for an additional manufacturing method different from the primary method and will only count for project-specific extra credit.

For all projects, all additional prints must adhere to the following specifications outlined in the next section. Prints that violate any of the specifications will be rejected and will not be printed nor count for extra credit for eligible prints.

Advanced Prints

For any group considering an advanced print through the MakerSpace:

• One person in the group must have completed the training on the machine prior to making the request.
• Groups must fill out the MakerSpace/EG1004 Print Request form and get approval from a ProtoLab TA before going to the MakerSpace to complete the print.
• For approval, you must present the file that you wish to print as well as making sure the specifications of the print line up with what was entered on the form.
• After filling out the form, you will have a week to complete the purchase otherwise it will be voided.

3D Printing & Extra Credit Specifications

All prints:

• Maximum Duration 12 hours; prints that exceed this limit will be assessed for feasibility with a different manufacturing method
• All submissions, including non-extra credit submissions, require a minimum of one .STL file and one .3MF file contained in a .ZIP folder. Submissions missing either file type will automatically be denied
• Original Design & Content
  • Must be different from other groups’ submissions
  • Must not include figures or models from other sources or .STLs generated using image converter softwares
  • Must be complex; will be judged by ProtoLab TAs and the Prototyping Committee

Logos:

• Maximum material weight does not exceed 15 g total
• Can be one or two colors
  • One-color logos are mandatory for all SLDP groups
  • Two-color logos are extra credit for all SLDP groups
  • Submission of two .STL files and one .3MF file containing both .STL files arranged and properly set for dual color (dual extruder) printing
• Logos must be integrated with your project in some way
• Must be original content
  • Cannot be exclusively text or a simple geometric shape
• Correct file types must be submitted to 3D printing submission tab
  • Must be exported as .STL from CAD program with correct scaling (make sure the document units are set to mm before exporting)
  • Must be exported as .3MF from Ultimaker CURA with correct scaling (make sure the document units are set to mm before exporting)

Figure 1: Example of a good logo

Figure 2: Example of a bad logo

HIR Models:

• Stackable Floorplan
  • Maximum Size 8 x 8 x 8 in, Maximum Weight 300 grams, Maximum 1 Color
  • Model should be equally scaled compared to the floorplan
  • Floors should fully nest with each other; features spanning multiple levels should still be aligned
• Exterior Model (counts for project-specific extra credit)
  • Maximum Size 8 x 8 x 8 in, Maximum Weight 300 grams, Maximum 1 Color
  • Model should be equally scaled compared to the floorplan
  • Features on each floor should be reduced/removed
  • Model should contain the full detailed exterior of the building

RAD & VEX Parts:

• Maximum Size 11 x 11 x 11 in, Maximum Weight per part 300 grams, Maximum 1 Color
  • Note: Maximum size includes the use of two build plates. Part must be able to be broken down to fit on printer
  • All prints that are past 3 x 3 x 3 in will be evaluated for if a different manufacturing method can be used or if the design could be changed
  • All parts that are past 5 x 5 x 5 in and are resubmitted due to a design change cannot be printed more than twice
• Printed parts must be able to assemble without the use of tape or glue
• Printed parts used for VEX course modifications are not permitted for use

Submission and General Guidelines

• Submission of your 3D designed parts will take place through the EG website using the “3D Printing Submission” tab of the left menu. DO NOT USE THE NORMAL SUBMISSION TAB. Submit your .STL files and .3MF files in a .ZIP file to the website.
• Make sure to submit an .STL with the correct scaling.
  • If you choose to build your model in in, remember to convert to mm before saving the .STL
• Please name the .STL files in the format Section_Project_PrintType_FileNumber i.e. A1_HIR_Logo_1, and the .3MF in the format Section_Project_PrintType. Please make sure the colors selected match the file number of the .STL and selected extruder in the cura setup (i.e. A1_HIR_Logo_1 should match your Color 1 option and Extruder 1 in your Cura setup).
• After your submission has been received, you will need to meet with a Proto TA to have your print approved during Protolab hours.
• If you are a RAD group, you have the option to self-print your design (if it is NOT a Logo) at the MakerSpace. If you are a RAD group, please only submit non-logo prints to the website if you want Protolab to print your design. The same applies to LAZ and MRR group wanting to manufacture a robot part or course modification.
• You can check the status of your print from the “3D printing Submission” tab. “Pending” means your print is in the process of being approved. “Approved” means your print is in the queue to be printed (“Denied” means you will need to make changes and resubmit.) “Printed” means your print is finished. “Picked Up” means your print has been delivered.
• As you are submitting your 3D designs for your logos, course modifications, or robot parts, please keep in mind the requirements posted on the EG Manual. If you have any further questions, please email prototyping@eg.poly.edu.
• RAD: Prototyping TAs will have the final decision over whether or not a part should be 3D printed or manufactured using another method. Also, while some parts submitted for 3D printing may be taken from preexisting designs online, your end result should still be an original design in order to not violate NYU’s academic honesty guidelines.

Deadlines

• Initial STL file submission for mandatory prints is due by Benchmark A (Week 7)
  • The 3D printing process can take multiple revisions, you are required to submit the first attempt by Benchmark A, but you will be allowed to make any modifications until the final deadline of Benchmark B.
• STL file approval for prints is due by Benchmark B (Week 10)
  • You must meet with a Protolab TA during Protolab hours to get your print approved. You cannot get your print approved without meeting with a Protolab TA. Your print will not be processed if it is not approved.
  • If you miss the Benchmark B deadline, subsequent submissions will not be considered. All submissions must be approved by this deadline (with very limited exceptions).
• Printed part by Commissioning Deadline (Week 14)
  • You must have picked up your printed part by commissioning.
• Above deadlines are applicable to mandatory logo prints, extra credit prints fulfilling the mandatory logo print requirement, and all SLDPs extra credit prints.
• All non-mandatory prints must be submitted & approved at least one week prior to Commissioning deadline (Week 13)
  • All prints approved before this deadline will be printed. If ProtoLab fails to deliver on an approved print request, please consult RAD mentor/recitation professor on adjusting project deliverables/expectations.
  • All prints submitted/approved after this deadline are not guaranteed to be fulfilled. Project deliverables/expectations cannot be negotiated due to unfulfilled print requests after this deadline. Plan accordingly.

Design Considerations

• Make a flat bottom: A large flat bottom increases the adhesion between the build platform and the part, keeping the part from shifting around during a print.
• Keep overhangs close to 45 degrees: Each layer of a 3D print needs to be supported from below. You can avoid adding additional supports to a print if all the overhanging parts are at no more than a 45-degree angle from vertical.
• Avoid thin walls and thin columns: Thin walls and columns often do not come out well. The thickness of a thin wall should be a multiple of 0.35 mm. Thin columns will usually come out distorted because they melt under the nozzle.

Software

To design your logo you will need any CAD software as well as Cura. There are many options for software that can be used, the only necessary feature is that the software can export files as an .STL (stereolithography) extension. Some examples of recommended software:

• Autodesk Fusion 360 – Free student edition
• Autodesk Inventor – Free student edition
• 123D – Free (Online)
• TinkerCAD – Free (Online)
• Blender – Free (Open source)
• OpenSCAD – Free (Open source)
• Solidworks – Available in NYU computer labs
• Rhinoceros – Free evaluation available for MacOS

To make a 2 color design you will need to save your logo in two separate .STL files (one for each color) and submit both as a .zip file to the website. The two files are then imported into CURA and aligned, with separate extruders selected for each color.

Cura

Cura is a critical piece of software for our 3D Printers. STL files do not contain the instructions the printer needs to position the extruder; to do this Cura “Slices” the model. This process analyses the 3D models that have been imported and slices them into individual layers that the printer can lay down. The software also determines which extruder to use, which, in turn, decides the color of the filament used.

Toolbar

The toolbar on the left side of Cura allows files to be imported and some final adjustments on the object before slicing. There are 9 functions available:

• Move: Translate the model in the X, Y, and Z directions
• Scale: Scale the model in the X, Y, and Z dimensions in mm or by a percentage.
  • Uniform scaling: Ensures that the object stays in the correct proportions.
• Rotate: Rotate the model in the X, Y, and Z dimensions by dragging the rings around the object.
  • Snap Rotation:Rotates objects in increments of 15 degrees.
  • Lay Flat: Adjusts the nearest flat edge of the object onto the platform.

• Mirror: Mirror the object with respect to a chosen axis. There are six arrowheads, two for every axis, and clicking on the arrow will mirror the object in the desired direction.
• Support Blocker: Select specific areas of the model where support does not need to be generated.
• Per Model Settings: Allow specific settings to be applied to different models on the build plate.
• Print Selected Model with Extruder 1/Extruder 2: With each option, select the desired extruder for each part of the model.
• View Types
  • X-ray: Makes model transparent to aid in detecting any missing or erroneous internal geometry.
  • Layers: Shows the layers to be printed, and is only available after the part has been sliced.

Part placement onto the build plate is a crucial step in preparing a Cura print file. One of the most common reasons for print failure is a poorly oriented part. The key is to minimize the overhanging elements of the model.

Importing Files

To create a multicolor print, at least two STL files must be imported, each file will use one extruder. To import the first file, click the “Open file” button on the top left.

Select one of the two files that is used in the design; it should load into the build-plate window. Next add the second file with the same method.

Selecting Colors

Because the Ultimaker 3 is a dual-extrusion printer, it allows prints to have two colors, but it is important to choose the correct corresponding extruder to allow the print to have the correct color on its parts. By default, parts with extruder 1 will appear as a light yellow color while printing with PLA, and extruder 2’s parts will appear as a darker yellow. To assign the extruder to a specific part of the print, first select the part, then choose extruder 1 or 2 on the left sidebar.

Figure above shows how parts will appear as different colors when selected under the two extruders.

Printing Settings

Once everything is placed correctly and extruders have been selected, it is then necessary to ensure the ideal print settings are chosen. On the right side, there is the settings panel where different settings can be chosen for each extruder. Since only PLA material will be used, make sure to choose both “AA 0.4” and “PLA” options under “Print core & Material.” Next, under “Profile” are a set of pre-created settings from CURA:

• Fast print (0.2 mm): Makes a quick print but with lower quality

.

• Normal (0.15 mm): Decent quality print with an acceptable print time. This profile is applicable to most prints.

• Fine (0.1 mm): Good quality print.

• Extra Fine (0.06 mm): Prints with a very smooth surface quality.

Most of the time, the print will be completed with the Normal profile. Under “Print Setup,” there is a toggle for “Recommended” versus “Custom.” Custom settings allow for more in depth adjustments, whereas recommended settings have the few necessary settings for overall adjustment. Below explains the settings more in depth:

• Infill: the amount of infill wished to have in the print. Avoid printing solid parts (100% infill) unless ABSOLUTELY necessary. The denser it is, the longer it will take. 20% is sufficient for most prints.

• Generate Support: If there are any parts of the print that has overhanging parts, selecting this option will allow a support structure to be generated below it. This structure can be removed after the print is finished.

• Support Extruder: Choose the extruder that will print the support structure; usually it should be the same extruder as that part of the print.

• Build Plate Adhesion: This option adds a brim or raft around the base of the model to ensure that the print sticks to the build plate. Especially important to have this feature active for smaller parts.

After the model has been sliced (prepared for printing), selecting “Layers” under “View” will show a layer-by-layer preview of the print. On the lower right corner, you have the option to edit the name of your file, view the dimensions of your print, as well as the estimated print time and filament usage. If the print exceeds the required dimensions or material use, it should be rescaled or redesigned until it meets the requirements.)

To view print time and material use

Once the material usage has been confirmed and the correct settings have been chosen, click “Save to File” and a .gcode file will be generated for printing. If a USB is inserted this will read “Save to Removable Drive”. Note that once a print has been sliced and saved as a .gcode file, it cannot be changed and the settings can not be viewed. Settings can only be adjusted with a .stl file. If you wish to save the current settings, make sure to go to “File” > “Save Project.”

Common Problems

If two parts cannot be merged or placed together-

• Cura, by default, drops the objects on to the build-plate and keeps objects apart. The following steps are needed to combine the filler rectangle within the keychain:
  • Under “Preferences”, select “Configure Cura”
  • Under “Viewport behavior,” make sure to deselect both “Ensure models are kept apart” and “Automatically drop models to the build plate” if they are not already deselected
  • Save your preferences
  • Return to the buildplate and make sure both objects are lying flat on the build-plate by using “Rotate” => “Lay Flat”

If Lay flat option places the object on an angle-

• It is very important to make sure that the print is flat on the build plate. However, sometimes due to the way that the model was built, the Lay Flat option won’t be able to correctly orient the object

• To fix this problem, you can:
  • Adjust it by eye with the rotate tool
  • Make sure the Z value is 0 mm under “Move”

• By holding down the right key on a mouse and dragging, you can access whether the print is flat on the build plate.