Goal this week is to cut some things using the lasercutter and vinyl cutter. Together with Heidi. I set on a quest to find the kerf of our laser. The rest of the week I worked on making something on the vinyl cutter and lasercutter.
I started on the vinyl cutter, a machine that I am already familiar with. When Emma saw me making some lame t-shirt stickers so she challenged me to make something that can move - and Cecilia challenged me to make something that can change color. So I accepted the challenge. Also I made a press fit kit on the lasercutter.
The lasercutter is such a fun machine, the cutting is great to look at, it gives quick results and it is easy to learn. Because this machine is so easy going it can easily be forgoten that it is a dangerous machine. Reasons why it's dangerous: 1) It uses a powerfull laser that cuts through (most) materials, 2) The machine doesn't stop by itself if there is a issue (think broken parts, fire, toxic materials).
So the basic rules that go with this machine are as follows:
USB drive BRM Lasercutter 1612 - CO2 100W - workarea 1200x1600 mm
Roland GS24 vinyl cutter - (55 degrees blade)
Corrugated cardboard 3mm
The laser tube can be found hidden somewhere in the machine, often in the back behind a closed door. The lasertube is a large glass tube that is filled with CO2 gass and has a water cooling system inside. If you run electricity through the tube a invisible light beam comes out of one end and hits into a small mirror that sends it to the next mirror that is moving on the Y-axis and on to a thirth mirror on the X-axis. The last mirror also bends the beam vertically into a lense. The lense converges the beam onto the material. Very similar to making a fire using a magnifiyingglass.
The lasercutter might be one of the most loved tools in the lab because it's so effective at making cool stuff in a super easy way. It only understands two file formats, bitmap and vectors and the most important settings are speed and power. So when you have your material, design and settings you have everything you need to make something cool.
The best settings are the fastest settings giving you a good result. It's different for each material and machine. Most labs offer a list of recommended settings. Speed is set in (roughly) milimeters per second (0 - 400) and power in a (relative) percentage (0% to 100%). In your design you can give different parts different colors. Each color represents different settings.
There are also different ways of cutting. There is cutting, light cutting, engraving and dot. Cutting is the most simple one, this is where the laserbeam cuts all the way through the material. Light cut is where we don't want the material to be cut but just for the laser to mark where the line is. This is very similar to engraving but much faster. Engraving can be done with both vector and bitmap files - the machine engraves between two lines to fill up the design or it switches the power on and off depending on the colors of the bits. Dot is not used that often, but this is when the laser creates a dotted line good for folding.
Step by step guide
When cutting things on the lasercutter it doesn't take into account the material being removed. Although in most cases this is not a issue it can be pretty annoying when you are making thinks that should perfectly fit. The slit made by the laser is called the kerf and it changes slightly depending on the machine, material and settings (but also hummidity, focus, age of the lasertube, place on the bed, etc.). So if you want to perfectly make something to fit you need to make a test - measure - and adjust to compensate for the kerf. The kerf should be around .2mm but it can easily be tested.
Our goal for the test was to make a special ruler that can quickly give you a indication of the kerf. By sliding a fixed object and seeing where it gets stuck on the ruler it should be possible to tell the kerf. Once you have a perfect ruler you can use it for different materials. But first we had to figure out the kerf for the material we wanted to make the ruler of (Black acrylic - 4mm). And... we also tried cardboard.
The first thing we cut was a simple squares (10x10mm) from both materials. This table was made with a markdown tables generator.
As you can see the square is not the size we actually intended. The kerf material removed from the acrylic is .36 mm - this is the kerf. To compensate for this we need to offset the square towards the outside by .18 mm (.36 mm/2).
To get a better average we quickly moved on to a better design that was more easy to measure. 10 small squares of 10 by 10 mm. I quickly drew this in Illustrator and made sure not to draw any overlapping lines.
By cutting them in a little frame the squares can be moved to one side and the space left behind (red) can be measured and used to calculate the kerf.
|+ 0.09 mm
|+ 0.11 mm
|+ 0.155 mm
Acrylic black - 2.39mm
Acrylic transparent - 2.76mm
Cardboard - 3.74mm
At this point we realised a flaw in our design - the squares we cut out can be turned when put together again. Rectangles would have been better. After checking with the results from other students we realised that the difference was negligible. So we decided not to redo our test.
Challenge: design, lasercut and document a parametric press-fit contruction kit. I have a lot of old cardboard from a previous project - so for this project I wanted to do something that had some size to it but also functionallity. My first thought was making something furniture like and I got really inspired by Bloxes. The next day I decided to make a system for storage or showcasing - 'boxes' that can be stacked together, stand alone or wall mounted. The perfect shape... hexagons.
I started with a quick sketch on paper to figure out what parameters I wanted to customise. This wasn't a complete list yet but it gave me a good starting point.
Next on I started with a small test (a basic part) to see how difficult it was to draw this way in Fusion360 but also to test my workflow for the lasercutter. A square with a negative space for the spacer to fit in and two spacers.
My simple test part turned out to be based on quite a few parameters. This part is probably the most complicated part. I drew everything true to size and added a final parameter to my list: kerf. By selecting everything and giving it an offset of 'kerf/2' towards the outside the design is now ready to cut. I used the kerf settings that me and Heidi calculated and it worked perfectly. There was only one big flaw in my workflow - Fusion exported all lines (including construction lines). In the lasercutter software I manually removed them.
After this I started to draw my other parts improved my workflow. Two things improved my workflow and made them more efficient. The first was not to use the kerf in Fusion but instead do this in Lasercut 5.3 (Tools > Offset polygons). The improvement was to get rid of all the construction lines.
From left to right you see the panels (width and height can be changed - tabs change depending on material thickness), the test square, a spacer tab (spacing height and width can be changed - slot and tabs change depending on material thickness) and the hexagon back (radius can be changed and the slots change depending on the tab settings and material thickness). Ideally the panels are made out of a single piece of cardboard but unfortunalty I ran out of time to figure out how to create a good workflow for creating folding lines within Fusion.
The kit can be assembled in different ways, boxes can be connected to each other and can be flipped to make a two sided cabinet. I made three different configurations - a wall display, a floor lamp and a house for my guinea pig. I will improve this design to make the panels connected to each other so it becomes structurally stronger. Also champfers would've been usefull. For now I solved this with some colourfull tape that also looks pretty nice. The holes in the back panel can be used for wall mounting. The boxes need at least one screw to hang from and I made a parametric design for a cover of the screw. The cover can be 3D printed.
vinyl cutters cut through materials using a tiny blade that follows the lines of your design (vector). There are a lot of materials that can be used to cut. The most simple ones are vinyl, flexfoil and flockfoil - these already have a backing adhesive and can be cut with a regular blade. Than there are thicker materials like masking vinyl for sandblasting or reflective foil with industrial quality. Using a cutting mat it is even possible to cut fabrics, rubber, thin metal sheets, cardboard or whatever you can think of that you would also be able to cut with scissors.
Roland GS24 vinyl cutter - (55 degrees blade)
Silhouette Cameo cutting mat Tweezers + weeding blade
White shiny cardboard
Transfer paper and/or foil
Vinyl (2 different colours)
There are only two important settings that can be adjusted for the vinyl cutter - speed and pressure (sometimes called force). Speed is calculated in cm per second and the force in grams of force. Intricate designs call for slower speeds while bulky designs can go at the highest speeds. Thin easy to cut materials need very little force but thicker stronger materials need more. The blade can also be replaced with different angled blades to improve performance or pens if you prefer to draw. Settings I used were 10cm/s at 150gf.
Step by step guide
In Illustrator go to File > Print. Click 'Setup'.
When the machine is done cutting remove the material by opening the lever again.
I made my design from last week during the computer aided design week is split up in three layers - top, middle and bottom. All layers are made from cardboard and the illustration on the middle one is made with two different layers of coloured vinyl.
It's a bit hard to see in the image but I made clipping masks for each 'scene' of the animation.
Here you can see two of the other scenes that are drawn without a clipping mask since these are really simple and made out of full circles.
The paper parts were definatly the easiest to make but scared me the most since I never tried it and the detail level of the grid pattern is quite high. I asked Jona from Oh Pop Up for some advise. She told me that she wouldn't make the holes smaller than 3mm and to cut at the highest speed (10 cm p/s) with semi high pressure (150gf) using multiple passes.
The cutting mat I used came with my vinylcutter (Silhoutte Cameo) and is 12 x 12 inch. The only cardboard I had at home was from the Hema, it weighs 210 g m2 and has bright patterns on one side and is white on the other. The cutting mat has a protective layer to keep it sticky that I had to take of. After this I used the grid on the cutting mat to position my material (right side up).
I made a test and started with 6 passes, this clearly cut through the material but also was clearly visible on the cutting mat. For the second test I only made 3 passes and this looked right - very little marking on the cutting mat and very sharp cuts. I cut all three parts and removed all the left overs from the cutting mat and put the protective layer back.
After this I had to cut the vinyl for the "image" on the middle layer. This is where I got a little bit worried because I forgot registration marks on the cardboard middle layer. Since the alignment needs to be really percice I needed a solution. If had known this beforehand I would've drawn some registration marks on the cardboard and both coloured layers. My solution was to cut the cutting line for the cardboard as well, this was a little bit more wastefull but worked really well. I cut both vinyl layers and peeled away everything that I didn't need. Using transfer paper I moved the first vinyl layer to the second. Since none of the colours overlap this was pretty simple. Using the surrounding shape it was also quite simple to align them. Using the backing paper with now both colours of vinyl I moved the stickers onto the cardboard. The aligning was a bit more tricky but with a set of extra hands it was quickly done.
I checked with the top cardboard if the image was visible and everything looked right. Than I glued the top and bottom layer in the corners together with the 'loose' middle layer inbetween. I think this project is pretty fun to make and I would love to make it out of wood with a string to hang it in four different orientations. If I were to make another paper one I would make some paper tabs to make the top and bottom cardboard in one piece and more profesionally glued together.