4. Computer controlled cutting¶
I wanted to build a geodesic dome. To do this, I have selected a construction on the following website and modified it according to my needs.
Construction¶
First I constructed the five and six corner pillars. I adapted this to the diameter that the geodesic dome constructor calculated for my example.
Afterwards I inserted a low circular column with the same distance to the ends. I tried to estimate how far an interlocking of 3mm MDF brings stability.
I set the parameters in order to be able to quickly adjust all dimensions in the event of dimensional changes. The most important parameter for me was the material thickness. I wanted to derive the connectors from these shapes later.
Next, I drew the bars with the angled faces on the ends that I wanted to dock onto the pentagonal and hexagonal columns. The circle should be intersected with.
Here, too, the most important parameter for me was the material thickness.
Then I connected the parts together so that they overlap. Here I made sure that I put together both a connector with five rods and a connector with 6 rods. Now I was able to pull off the bars from the original shape.
Next I added a smaller circle to the shape at the same height as the cutouts.
Now I was able to pull off the smaller circle at the right height and at the right angle in the material of the bars.
To check whether my strategy works, I put half the dome together so that it was clear that it would work.
I could now set exactly the material thickness that I need so that the parts hold together well with a little grip after they have been put together.
Now I still needed the DXF file to be able to continue working.
After saving the DXF files, I multiplied the parts with the MOI program and then opened them in Rhino. The data then went from Rhino to the laser cutter.
Lasern¶
I imported the file into Rhino for laser cutting.
I could make the required settings under properties.
The following window opened.
I only needed Vector because I just wanted to cut.
The following attitudes have worked best for me.
With Set I was able to set which one on the working surface of the laser should start with. To do this, move the white field as far as you need it.
I chose the upper left corner.
Print - the job goes to the machine¶
The first thing to do is to set the focus. This happens after a molded part, which is hooked in and is easy to adjust to the height of the workpiece.
Next, set Jog. To do this, it makes sense to switch on the small laser pointer, which shows you the exact starting point at which the cut will be made.
Before you start cutting, you have to switch on the suction so that the toxic fumes do not get into the work area and are instead filtered and directed outside.
Then I could start the job.
The chosen settings worked well.
The connections also had the necessary stability.
In the meantime I had thought about cutting out holes in the middle in order to be able to attach something later. For example, a paper that is cut to the shape to use the dome as a lamp.
To make the assembly a little easier, I made small notches at the larger angles on the hexagonal connector.
Assembling¶
Assembling something else¶
Here I oriented myself towards disney characters. It doesn’t look the same, but it goes in the same direction.
Cutting Plotter¶
Silhuette studio¶
Since we at silhuette have some cutting plotters in the FabLab, it makes sense for me to deal with the drawing software of this machine.
First I choose a pictogram that I could use for our new school fablab.
Here I am looking at “theounproject.com”.
But I won’t download the vector file because I want to test the tracing functions in Sihouette.
I take a detailed screenshot and copy the bild.jpg onto the workspace.
tracing¶
Now I choose the area to trace.
Now I click on trace and the edges of the pixel drawing are now vectors.
I can now click on the picture (.jpg) and drag it away.
I can also display the vector points and reduce them to the most necessary.
change Something¶
To clean them up or to change them, I have to break the linked path.
Now I could adapt the drawing to my needs and send it directly to the cutting plotter from this program.
To be able to send the job to the cutting plotter, I have to switch back to the send mode.
cut an adhesive film¶
Since I want to cut an adhesive film, I bring it to the size of the adhesive cutting pad and press it on.
Since the adhesive film is attached to a carrier that should not be cut through, I test the cutting depth. To do this, I insert the cutting mat with the foil into the cutting plotter and click on test.
Now that I see that everything is ok, I send the job to the machine.
The material is now removed that should not be glued on or used.
To stick the sticker on a door, for example, I use transfer paper, which sticks easily itself. With this I can pick up the finished product (the sticker) and
without anything shifting or sticking to another place in a distorted manner.
Here I should make sure that I spread the sticker so that no wrinkles can appear.
Last but not least, I can peel off the transfer paper and have attached the figure, the logo or whatever.
Silhuette PixScan¶
I downloaded a pdf papercraft file from the internet and found that I cannot use the vectors that were contained in the file without a great deal of effort.
Since the cutting plotter cameo 3 also has the pix scan substrate available to me, I would like to try it out.
First I printed out the pdf file on somewhat thicker paper.
Then I press the printed drawing onto the self-adhesive pix-scan film.
In order to be able to edit the file in the program, I take a picture of the pix-scan document with my mobile phone
and import it into silhuette studio.
Here I use the tracing function you test the threshold value. When the yellow edges are completely closed, you get a good vector drawing. I just want to trace the outer edge.
The result looks good so far.
I move the vector and zoom in closer to see the result. Then I’ll undo it.
In order to be able to send the work order (cut this part from the mat) to the machine, I first have to go into (Send) mode.
Depending on the material, I can choose what and how deep to cut.
I put the pixi scan cutting mat in the intended place and let the machine pull it in. I can then send the work order.
The machine first looks for the fitting markings in order to align itself so that the cut is made at the right point. Then she cuts out the papercraft part.
Unfortunately, the cut on the cutting mat is not as accurate as in the program. Still, it’s ok.
For further work, I run the back of the cutting tool over the dashed lines to be able to fold them more cleanly. Later I glue the parts together as neatly as possible.
group assignment - computer-controlled cutting¶
We measured the kerf with the group. It was 0.114mm. We also dealt with speed, power, frequency and focus.
This is the link to the page.
files for download¶
domeconnector5
domeconnector6
domepoleyellow
domepolered
