3D printing

What is 3D printing?

3D printing is creating a 3D model created using Fusion 360 and many other software. You can also 3D print items that are not normally created using subtractive manufacturing.


How it is done?

  1. Create a printable 3D design using Fusion 360.
  2. Converting the 3D design into a 3D representable file (STL or 3MF).
  3. Slicing the 3D representable file into layers using Cura slicer software.
  4. Converting the layers into instructions for the 3D printer (gcode).
  5. The 3D printer creates the 3D object.
Common characteristics that can be tweak
  • Layer height (extruded filament thickness)
  • Wall thickness
  • Infill percentages
  • Bridging and overhangs
  • Supports
  • Bed adhesion
  • Object orientation


3D design

I am making a box using a hinge to open and close. This product is printed in a single sketch and does not require any assembly. This product could not be easily made subtractive as many parts are required and to be assembled if the parts is made separately. Using 3D printing allow this box to be made in 1 single print. 

To create the box
1. Create a box with a dimension of 50mm x 50mm x 50mm.

2. Select shell tool and select all six faces of the box. Enter inside thickness of 3mm.

3. Construct three concentric circle, use dimension tool to size.
  • inner circle (pin) - diameter 3mm
  • middle circle (space between the knuckle) - gap between middle and inner 0.2mm
  • outer circle (knuckle) - gap between outer and middle 3mm

4. Create two (top and bottom) 45 degree line tangent to the outer circle, use dimension tool to size. This will be the wings.

5. Use construct tool and create a midpoint, select top and bottom of the point.

6. Split the box into half using the split body tool. Select the box and mid plane.

7. Extrude the bottom wing, knuckle, pin, space between the knuckle for 9.5mm.
 
8. To create the wing anchor on the other side of the box, change the start from "profile plane" to "object" and select the opposite face of the cube, extrude the same thing as step 7.

9. Extrude the pin. Change the extent type from "distance" to "to object" and select the opposite face of the cube. Change the operation to join.

10. Extrude the top wing. Select the top wing and knuckle, change the start from "profile plane" to "offset" of 10mm. Distance will be 30mm.

11. To inspect add section analysis.

12. To create a snap fit at the bottom, create a two-point rectangle of 2mm x6mm. Use the midpoint constraints to center the rectangle.

13. Extrude the rectangle into the body for 2mm with a taper angle of 45 degree, chamfer top edge of 0.5mm.

14. For the top part, extrude out the two-point rectangle of 2mm. Verify option to new body.

15. To create an attachment of the rectangle to the top part, use draft. For pull direction select face towards the center of the box, for the faces select the top. change the angle to 60 degree.

16. Combine the two bodies with the combine tool.

17. To create the snap fit part, extrude the two-point rectangle of 0.2mm using cut operation.

18. Extrude the two-point rectangle of 2mm with a taper angle of 45 degree, change the start from "profile plane" to "object".

19. Fillet the catch point of 0.3mm to ensure a smooth operation.

20. To animate the rotation of the lid, select new component, select from bodies and select top and bottom.

21. Use joint tool and select the knuckle and the pin. Rotate the lid around.


Printing

1. Select file and export as STL file.

2. Open STL file using Cura slicer software.
3. Verify settings.
  • Changed scale to 55%
  • Changed infill to 10%
  • Changed speed to 75mm/s

4. Save in SD card.
5. Print.
  • Insert SD card in the 3D printer
  • Select print
  • Select the correct file


Embed design



Hero shot



Reflection

In order to come up with an idea of what I should construct, I first looked up several festinating designs on Google. For examples, moving animals and movable gear shaped cubes or iris boxes . I couldn't find any tutorials on how to create that particular design. I tried multiple sketching and replicating the design, experimenting with various tools, but I was still unable to "make it perfect." I abandoned that idea and decided to create a hinge. A hinge is a component that allows the sides of an object to move, such as a battery door or a compartment door. As a result, I wanted to learn how to make a box that opens and closes using a hinge. The hinge is simple to construct because it is circular rather than irregular in shape. I have a better grasp of how different tools work and how to use them after watching a tutorial video.

Tweaking the setting on Crua is quite tricky. The quality of products is affected by the printing speed. Since my box is relatively small and does not have much details, I increased the speed from 50mm/s to 75mm/s with an infill of 10%. I have to changed the settings to meet the time requirement. Since 3D printing takes a long time to print, choosing the appropriate parameters is critical to minimizing material and time waste.


Reference

youtube. (n.d.). Fast Fusion 360 - 3D Print Hinges from a Single Sketch (and Snap Fit Lids!). [online] Available at: https://www.youtube.com/watch?v=KL1aj16ynf4 [Accessed 18 Dec 2021].