week3 group assignment

docs/Weekly_Group_Assignments/week03.md

 # 3. Computer controlled cutting
 
+## Instruction
 
-TEST 02/12
+characterize your lasercutter's focus, power, speed, rate, kerf, joint clearance and types
 
-This week I worked on defining my final project idea and started to getting used to the documentation process.
+## Lesercutter we used
 
-## Research
+The following is information of the Lasercutter used at Fablab Kannai.
 
-"Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
+![](../images/week03/lasercutter.jpeg)
 
-> "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
+Universal VLS 2.3
 
-## Useful links
+- Work area is 406x305x102mm(16"x12"x4")
 
-- [Jekyll](http://jekyll.org)
-- [Google](http://google.com)
-- [Markdown](https://en.wikipedia.org/wiki/Markdown)
+- 30W CO2
 
-## Code Example
 
-Use the three backticks to separate code.
+## focus
 
-```
-// the setup function runs once when you press reset or power the board
-void setup() {
-  // initialize digital pin LED_BUILTIN as an output.
-  pinMode(LED_BUILTIN, OUTPUT);
-}
+![](../images/week03/focus.png)
 
-// the loop function runs over and over again forever
-void loop() {
-  digitalWrite(LED_BUILTIN, HIGH);   // turn the LED on (HIGH is the voltage level)
-  delay(1000);                       // wait for a second
-  digitalWrite(LED_BUILTIN, LOW);    // turn the LED off by making the voltage LOW
-  delay(1000);                       // wait for a second
-}
-```
+- Lens: 2.0 inch (2.54 x 2 mm)
+- Z Axis resolution 0.1mm
+- Defocus +5.0, +4.5, +4.0, +3.5, +3.0, +2.5, +2.0 +1.5, +1.0, +0.5, 0, -0.5, -1.0, -1.5
+- material we used : card board
 
-## Gallery
+![](../images/week03/laser_1.png)
 
-![](../images/sample-photo.jpg)
+set Z=0.6 as starting point(zero) and change z parameter by 5mm
+Unexpectedly, there is not a significant difference from the front viewpoint
 
-## Video
+![](../images/week03/focus_board.jpg)
 
-### From Vimeo
+However, looking at the back we find the board is not cut enough above 3.5mm
+![](../images/week03/focus_result.jpg)
 
-<iframe src="https://player.vimeo.com/video/10048961" width="640" height="480" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
-<p><a href="https://vimeo.com/10048961">Sound Waves</a> from <a href="https://vimeo.com/radarboy">George Gally (Radarboy)</a> on <a href="https://vimeo.com">Vimeo</a>.</p>
+## Power, Speed, Rate
 
-### From Youtube
+The data we used for power, speed, rate test
 
-<iframe width="560" height="315" src="https://www.youtube.com/embed/jjNgJFemlC4" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>
+ - Power is laser output strength
+ - Speed is speed of advancing laser
+ - rate is PPI = pulses per inch
 
-## 3D Models
+![](../images/week03/psr.svg)
 
-<div class="sketchfab-embed-wrapper"><iframe width="640" height="480" src="https://sketchfab.com/models/658c8f8a2f3042c3ad7bdedd83f1c915/embed" frameborder="0" allow="autoplay; fullscreen; vr" mozallowfullscreen="true" webkitallowfullscreen="true"></iframe>
 
-<p style="font-size: 13px; font-weight: normal; margin: 5px; color: #4A4A4A;">
-    <a href="https://sketchfab.com/models/658c8f8a2f3042c3ad7bdedd83f1c915?utm_medium=embed&utm_source=website&utm_campaign=share-popup" target="_blank" style="font-weight: bold; color: #1CAAD9;">Dita&#39;s Gown</a>
-    by <a href="https://sketchfab.com/francisbitontistudio?utm_medium=embed&utm_source=website&utm_campaign=share-popup" target="_blank" style="font-weight: bold; color: #1CAAD9;">Francis Bitonti Studio</a>
-    on <a href="https://sketchfab.com?utm_medium=embed&utm_source=website&utm_campaign=share-popup" target="_blank" style="font-weight: bold; color: #1CAAD9;">Sketchfab</a>
-</p>
-</div>
+Only the column of power=40 is displayed and Command +P
+
+![](../images/week03/laser_1.png)
+
+launch UCP software and select Medium Density Fiberboard at material database
+
+![](../images/week03/laser_2.png)
+
+cut the cardboard in each setting
+
+![](../images/week03/laser_5.jpg)
+
+we found that the best setting for this cardboard is here
+**Power=70, Speed=20, PPI=250**
+
+![](../images/week03/laser_5.5.jpg)
+
+
+## kerf
+
+in order to measure kerf, we use the data below.
+- 10 sticks (11 cuts)
+- 1/2 + 9 + 1/2 = 10 Kerf
+
+![](../images/week03/kerf_test.png)
+
+cut the cardboard in the setting below
+**Power=70, Speed=20, PPI=250**
+
+![](../images/week03/laser_6.jpeg)
+
+but the part of cardboard was not cut completely
+
+![](../images/week03/laser_7.jpeg)
+
+
+So we try again to cut it under a little stronger setting :
+**Power=70, Speed=10, PPI=250**
+This time I was able to cut it off completely.
+
+lay them side by side and measure the total lengry by digital caliper
+
+![](../images/week03/laser_8.jpeg)
+
+
+10 Kerf = 100 - 97.55 = 2.45 mm
+
+**kerf = 0.245 mm**
+
+## Joint Clearance for pressfit
+
+Measure thickness of the cardboard 5 times and calculate the average for them
+
+2.9
+2.83
+2.85
+2.88
+2.79
+
+ave.
+**thickness = 2.85**
+
+we use the data for joint clearance test
+![](../images/week03/comb-test.png)
+
+set the result of experiment as parameter of thickness and kerf
+![](../images/week03/laser_8.5.png)
+
+cut the comb
+![](../images/week03/laser_9.jpeg)
+
+and we test which slit is the best fit
+
+![](../images/week03/laser_10.jpeg)
+
+As a result, we get the final answer of the joint clearance as 0.1
+
+so I found value of the best slit width below
+
+Thickness 2.85
+-Kerf 0.245
+-Joint Clearance 0.1
+=2.505
+
+
+## Files we used
+- [Power, Speed, Rate test](https://fabacademy.org/2022/labs/kannai/Instruction/images/week02/fa2021-group-assignment-power-speed-ppi.svg)
+
+- [Kerf test](https://fabacademy.org/2022/labs/kannai/Instruction/images/week02/fa2022-group-assignment-laser_kerf_x10%20.f3d)
+
+- [joint clearance test](https://fabacademy.org/2022/labs/kannai/Instruction/images/week02/fa2022-group-assignment-comb-test.f3d)