3D Scanning & Printing

Task

I have this week worked with 3D scanning and printing and completed the following:

• Tested our 3D-printes ability/limits to print semi-circular arcs.
• Designed and 3D-printed an assembly part for my final project.
• Used photometry to convert pictures to a printable moddel.

3D print for final design

3D-printers allows for construction of elements which would other wise require assembling of multiple parts. I identified a structural weak point in my revised idea for the final project - and developed a design of a structural assembling part. The purpose of the design is to fasten 2 layers of wood to each by using predrilled holes. I created a parametric design in Fusion 360, which I exported as an STL, imported in Cura and 3D-printed.

Arc test

I have this week worked with 3D scanning and printing and completed the following:

• Printed a semi-circular arch
• Increased it's size to identify a upper limit

It was my hypotesis that the 3D-printer would increasingly be challenged in printing the over hang as the width of the arc was increased.

Conclusions

I discovered that a 3D-printers ability to create a simi-circular arc might be a matter of the relation between arc thickness and span of the arc.

• Thinner arch = smaller possible span of the arc

I will in the future make further tests in order to identify the critical ratio of a range of materials.

3D-printers allows for construction of elements which would other wise require assembling of multiple parts.

I have identified a structural weak point in my revised idea for the final project - and developed a design of a structural assembly part. The purpose of the design is to fasten 2 layers of wood to each by using predrilled (machined) holes.

I created a (yet quasi) parametric design in Fusion 360, which I exported as an STL, imported in Cura and 3D-printed.

Reflections & Iterations of the Assembly Part

I intend to make revisions to the first prototype of the assembly part. Revisions might include:

• Addition of a screwdriver slot.
• Improved aestics in the head.
• Addition of something that makes the outer fit tight.
• Slimmer buttom.
• Printing wih less support.

I used the VisualSFM_OS_X_Mavericks_Installer created by Dan Monaghan and followed the instructions on GitHub with the following modifications:

Step 4: The command should be without "_mavericks":

$ sh vsfm_os_x_installer.sh

Step 8: I received the following error message:

libsiftgpu.so failed to build. Halting

I found an Issue dealing with that error message on GitHub, I downloaded SiftGPU, unzipped, renamed and moved it into the folder. I then disables line 250 to 258 in the above mentioned installer and replaced every sed -i with 'sed -i'. I then ran installer again and this time accepted the prompted installation of version 2.7.6 of X11.

ERROR: unable to load libsiftgpu.so

ERROR: unable to Load libpba.so (Multicore Bundle Adjustment). Make sure you have libpba.so in the VisualSFM

Workflow for Photometric 3D Scanning

I followed this instruction from Hackaday and did the following to transform a range of photos to a 3D printable model:

• Set the scene (right object, light, turn table)
• Took pictures
• Created point cloud and dense point cloud in VisualSFM
• Opened and cleaned the dense point cloud using Meshlab
• Merged Dense point cloud with the OptionXXXX.ply file.
• Generated a Mesh using the Screened Poisson Surface Reconstruction command.
• Exported the Mesh as a .OBJ-fil.
• Opened the .OBJ-file in Meshmixer and made it solid.
• Exported the solid model as .STL.

Design Files

• Simple Bridging Test Arc (.STL, Online)
  by AFS170580 CC BY-NC-SA 3.0
• Assembly Part in Fusion 360 (Online)
• 3D scan of Jelling Stone (18 mB, .MIX, Online)
• 3D scan of Jelling Stone (52 mB, .STL, Online)

See more

Visit my project development site and see further about 3D-printed assemble Part.