3. Computer-controlled cutting¶
This week I learned about computer-controlled cutting technologies, mainly about vinylcutter and lasercutter.
3.0 Assignment of this week¶
3.0.1 Group assignment¶
Characterize the lasercutter’s focus, power, speed, rate, kerf, joint clearance and types.
3.0.2 Individual assignment¶
Cut something on the vinylcutter.
Design, lasercut, and document a parametric construction kit, accounting for the lasercutter kerf, which can be assembled in multiple ways.
Extra credit: Include elements that aren’t flat.
3.1 Characterize the lasercutter(as group assignment)¶
3.1.1 Facilities¶
3.1.1.1 Speedy 100¶
The primary lasercutter in our lab is ‘Speedy 100’.
Technical data of Speedy 100
| Working area (W x D) | 610 x 305 mm |
| Max. height of workpiece | 170 mm |
| Laser type | CO2 |
| Laser power | 30W |
| Laser class | 2 |
| Focal length | 2 inches (approx. 5cm) |
| Max. processing speed | 2.8 m/s |
| Max. acceleration | 40 m/s² |
Material suitabiity (Manufacturer information)
| Material | Engrave | Cut |
| Acrylics | ✔ | ✔ |
| Glass | ✔ | - |
| Plastic sheets | ✔ | ✔ |
| Leather | ✔ | ✔ |
| Metal | - | - |
| Paper | ✔ | ✔ |
| Plastics | ✔ | ✔ |
| Stone | ✔ | - |
| Textiles | ✔ | ✔ |
| Wood | ✔ | ✔ |
3.1.1.2 Snapmaker 2.0¶
We also have another machine ‘Snapmaker 2.0’ which has a smaller laser head.
Technical data of Snapmaker 2.0
| Working area (W x D) | 320 x 350 mm |
| Max. height of workpiece | 330 mm |
| Laser type | 450 nm blue laser diode |
| Laser power | 1.6W |
| Laser class | 4 |
| Focal length | 1 inch (approx. 2.5cm) |
Material suitabiity (Manufacturer information)
| Material | Engrave | Cut |
| Acrylics(opaque) | ✔ | ✔ |
| Glass | - | - |
| Plastic sheets | ✔ | ✔ |
| Leather | ✔ | ✔ |
| Metal | - | - |
| Paper | ✔ | ✔ |
| Plastics | ✔ | ✔ |
| Stone | - | - |
| Textiles | ✔ | ✔ |
| Wood | ✔ | ✔ |
3.1.2 Cutting tests¶
As I am an only student in my Lab this year, so I refered the previous students’ archives and recycled the cutting template.
3.1.2.1 Inspection of the original data¶
I opened the template data( parametric_slot.f3d ) used to laser-cut test pieces by Fusion 360 and checked the contraints and user parameter settings.
Original sketch:
Original parameters:
3.1.2.2 Improvement on the data¶
The original data seemed better to be improved and simplified by introducing more constraints(equal, parallel, etc.), so I revised the data and saved it as Version 2( parametric_slot_V2.f3d ).
Revised sketch:
Revised parameters:
Output data files:
parametric_slot.ai
parametric_slot.f3d
parametric_slot.dxf
.ai format data can be opened by Illustrator and sent to the cutting software of ‘Speedy 100’.
.f3d is a standard Fusion 360 file format. It is useful to add various parametric constraints to the data.
.dxf format data is neccessary for the cutting sotware of ‘Snapmaker 2.0’
3.1.2.3 Test by ‘Speedy 100’¶
I ran the cutter using the template data with settings below and got a pretty good result.
| Material | Cardboard |
| Thickness | Approx. 3mm | Power | 90% |
| Speed | 280 mm/s |
| Pass | 2 times |
I measured the cut piece and found that the slots were just in size as designed.
I also measured the cut remains and found that it was Approx. 0.15mm nallow per line compared with the original design. I guess that the value shows a diameter of the laser beam.
I tried the test fit using a couple of the test piece. They fit best at 2.8mm. It would indicate the actual thickness of the card board.
Troubles I encountered and solutions I found:
Trouble: Laser beam didn’t cut through the material
Solution: I checked ‘Cut job’ option in cutting software setting menu and it went well
3.2 Design and documentation of a parametric construction kit¶
3.2.1 Original design development¶
I am working on my own construction kit design(Pen stand). I tried to design the sketch with minimum model parameters and maximum constraints and user parameters.
Sketch:
Parameters:
Solid:
Troubles I encountered and solutions I found:
Trouble: Over constraint errors
Solution: Managed to fix errors by changing constraint locations
Output data files:
PenStand_v3.f3d
penStandV3_1.dxf
Laser cut parts:
Construction:
Laser cut parts were press-fitted into a final product. As fits were a little soft, so I will fine-tune the slot size by changing a single parameter in the next try…
3.3 Cut something on the vinylcutter¶
3.3.1 Facility¶
The vinylcutter in our lab is ‘Craft ROBO PRO’.
Technical data of Craft ROBO PRO
| Cutting area (W x D) | 375 mm x 50 m |
| Paper size (W x D) | 484 mm Max. / 50 mm Min. |
| Max. cutting speed | 600 m/s |
| Cutting pressure | 0.2-2.9 N（20-300 gf） |
3.3.2 Cutting test¶
I cut a chinese character(kanji) as my personal sign on my smart phone. The character means ‘wing of insects’.
At first, I created vector data of the character using Inkscape:
Then I imported the data to the cutting software named ‘Graphtec Studio’:
I set the appropriate film roll to the vinylcutter and ran the job:
Machine running:
Machine setting:
Cut result:
I transferred the cut letter to the transfer film.
Finally I applied the letter to the back of my smart phone. Isn’t it cool?:
Troubles I encountered and solutions I found:
Trouble1: .svg format data exported from Inkscape couldn’t be opened by the cutting software
Solution1: Converted .svg format data to .eps format which was OK for the cutting software
Trouble2: The letter couldn’t peel off from the base paper because the cutting blade went too deep and base paper was damaged
Solution2: Decreased the exposure of the blade slightly not to cut through the base paper
Data files:
character.svg
character.eps
