Week5 : 3D Scanning and Printing


This week has three assignments:
1.Test the design rules for our printer.
2.Design and 3D print an object (small, few cm) that could not be made subtractively.
3.3D scan an object (and optionally print it).

● Test the design rules for our printer

The 3D printer I used is MakerBot Replicator Mini, and this printer was used for the first time. I used the default setting to print the test object which was downloaded from http://www.thingiverse.com/thing:704409. After finishing the first print, it had a problem of stringing or oozing. According to past experience, it might be the setting problem about extruder temperature, Z-axis travel speed, fan speed, retraction distance and retraction speed. So I draw two cones as test object for adjusting the setting parameter. After a series of tests, I found a set of setting for better quality of printting. The set of setting was below:

Extruder temperature : 185 degrees Celsius
Z-axis travel speed : 30 mm/s
Fan speed : 70% max power
Retraction distance : 4.5 mm
Retraction speed : 35 mm/s

Makerbot mini test object

figure 1 : Makerbot Replicator Mini and the test object.


first print Testing cones

figure 2 : First print and Testing cones.


test cones second print

figure 3 : Compareing three printtings with different setting.


setting vlue

figure 4 : The sheet of adjusting setting.


After adjusting the printting parameters, it was time to test the limit of this printer. I focused on testing the printting speed. This printer had advance setting of printting speed. The printting speed could be divided into Bridges, First layer, First layer raft, etc. So I designed three tests, which the all speeds of setting were default, decreasing 50% and increasing 50% of default setting. The layer height setted to 0.1 mm. The results of the these three test prints. I observed the printed object with increasing 50% default speeds setting had better quality than others.


The sheet of three defferent speed settings

figure 5 : The sheet of three defferent speed settings.


default speed default speed default speed default speed

figure 6 : The printting result with default speed setting. It looked had some gaps.


decrease 50% speed decrease 50% speed decrease 50% speed decrease 50% speed

figure 7 : The printting result with decreasing 50% default speed setting. It looked had some gaps and stringing or oozing.


increase 50% speed increase 50% speed increase 50% speed increase 50% speed

figure 8 : The printting result with increasing 50% default speed setting. It looked better than others.


● Design and 3D print an object (small, few cm) that could not be made subtractively.

I used Rhino to design a positive cube with a ball in it. Arrording to the limit test above, I used the better parameters setting to print my object. I still printed the object with original default setting for comparing. The result showed that the object with fixed parameters had better quality than using default parameters.

positive cube positive cube

figure 9 : Using Rhino to design a positive cube with a ball in it.


positive cube positive cube

figure 10 : Left picture shows the result of printting with default setting, and right picture shows printting with fixed setting.


positive cube positive cube

figure 11 : Left picture shows the result of printting with default setting, and right picture shows printting with fixed setting.


● 3D scan an object (and optionally print it).

I tried two types of 3D scanner, one was Sense, and the other was MakerBot Digitizer. Sense was a handheld scanner, I tried to scanner an little object which size was 11x4x6 cm. The scanning result was not good, and I failed many times because of the changging in focal length. So I cahnged to scan a bigger object, an toy bear head. I obtained the good scaned result just only one time. Then I used MakerBot Digitizer, an desktop scanner. It only could scan the small objects, so I choose an little toy sheep to scan. It needed to run the calibration process during the first used. Then I just only had to put the sheep on the center of the flat, the flat automatic turned 360 degrees to finish scanning. I could put the sheep with different angle and ran the process again to obtain the better resolution.

Sense bear head scanning result scanning result

figure 12 : Sense and sacnned an object.


MakerBot Digitizer calibration calibration scanning sheep

figure 13 : MakerBot Digitizer and sacnned an object.


● Source file

1.STL file of test object from "Thingiverse"
 2.STL file of test object I designed with Rhino.
 3.3D object I design with Rhino.
 4.STL file of 3D object I design with Rhino.
 5.STL file of scanning a toy sheep.