4. Computer controlled cutting¶
What should I learn this week?¶
Learning outcomes
- Demonstrate and describe parametric 2D modelling processes
- Identify and explain processes involved in using the laser cutter.
- Develop, evaluate and construct the parametric construction kit
- Identify and explain processes involved in using the vinyl cutter.
Have you? - linked to the group assignment page - Explained how you parametrically designed your files - Documented how you made your press-fit kit - Documented how you made your vinyl cutting - Included your original design files - Included your hero shots
Summary¶
This week I worked on getting to know the fab lab machines and learning how to cut vinyl and laser cutting.
At the group assignment we learned the tolerances and kerf of the Laser cutting machine, also we discovered the best cutting parameters for the material we were going to cut, in this case we cutted 3mm plywood.
You can find all the information of the group assignment on the link below.
Design Stage¶
For the vinyl Cutting I decided to cut my company Logo and paste it on my laptop. To create the vector I used fusion 360, started with a PDF I´ve already had and used inkscape to convert it to dxf format, than imported the file to fusion 360 to delete unwanted lines as you can see on the picture below.
The files of the logo are in the link below.
Vinyl cutting process¶
The software used in our Vinyl cutting machine is called Greatcut 4, wich we have a license at the lab machine but you can purchase it to control the vinyl cutter.
The following is the configuration we´ve used at the vinyl cutting machine.
- Cutting feedrate 30 cm/s = 300 mm/s
- Material width = 470.38 mm
- Material length = 30000 mm (this is just referential)
- Amount of cutting passes = 1
The first thing I had to do was to lift the lever on the back of the machine, after that I inserted the vinyl and put the lever back to the initial position, then I uploaded the DXF file to the software and started cutting.
I have chosen the yellow color because Yellow and black are my company colors. Since my computer is already black it complemented well.
the hardest part of the process was to remove the vynil to paste it in to the laptop, because in order to mantain the distances I had to remove it all at once.
I did my best and this was the result, I think it came out good enough.
Pressfit kit parametric design¶
As my daughter has this toy I thought about this being a practical an simple use of laser cutting and did an Hexagonal Puzzle kit.
For the parametric design I used fusion 360, the parameters I used were:
- kerf = 0.2mm (wich was found in the group assignment)
- Material thickness = 3mm
- The puzzle size = (50/3)*MaterialThickness
I used the tool regular polygon, the size of the radius of the polygon is puzzlesize/2.
for the slot of the puzzle I used the line tool, I draw a middle line with construction lines, later I made the distance on each side of half the material thickness minus half the kerf.
the depth of the slot is 4 times smaller than the material thickness.
after finishing the slot, I used circular pattern to reproduce the shape in the 6 places necessary.
For the last step I extruded the file using the material thickness parameter.
This parametric design will work proportionally for any laser machine or any thickness of the material and any kerf, the user just have to change the default kerf and material thickness and everything else will be automated.
In order to send the file to the laser cutter I projected and copied the design, 16 times usign the rectangular pattern tool.
The files of the dxf and the fusion 360 design are in the links below.
Cutting Process and Results¶
The laser cutter we have at the CIDI fablab is the JQ 1390 it is installed in a room with ventilation and fumes extraction.
The material I used was 3mm MDF, and the cutting parameters were the following:
- 20mm/s feedrate.
- 40% Laser power.
I decided to cut 18 pieces of the puzzle and got to the conclusion that it was enough to make good assembles.
The process took around 15 minutes, in no major issues happened
the first thing I build is kind of a flower, I think I came out pretty, the only thing missing were 2 extra pieces of the puzzle to make the leaves.
The last figure I made was just a picture of my imagination. I enjoyed this week assignment.