Using the Vinyl Cutter
Tip: the vinyl cutter will rotate your image before printing. If you were to print an arrow which appeared on the screen as pointing to the right, it would be reproduced pointing not the right in the cutter, but towards the back (inside) of the cutter.
Tip: If you want to print text used in an sdraw file, you must right click on the text and convert it to an object (e.g. a curve). Otherwise cam.py will not recognize the text in the .svg files (objects from the .svg file will appear, but the text items are initially treated as something different). Also, you will not be about to perform the logic operations on text items until you convert them to objects.
Loading your Material
Sending the File
- Cut off a large piece of material from the roll. This works better than feeding directly from the roll.
- Lift the rollers using the lever to the back right of the machine (seen in photo). Then move the rollers by hand to where you want them, i.e. the edges of your piece. If the blade is in the way, press enter and I believe it will move out of the way. If the rollers seem hard to move, girp them further back and they will move easily. Move the rollers to places marked in white so that they can catch the moving ridges, which you will see.
- Then put your piece under the rollers and use the lever to put the rollers down, holding the piece in place.
- Now there will probably be a message about sheet unloaded. Even if you're using a sheet, press enter and select "Roll." The machine will measure the width of your piece, but if you selected piece, it would measure other dimensions as well.
- Use the arrow keys to get to where you want your origin to be (remember, the origin will be the bottom left corner of the cam.py window, but the bottom right corner of your cutting due to a rotation). Press and hold the origin button until the message appears in the display that origin is set.
Force and Velocity
- To login to the computer, use the username and password written on the monitor. Then open a Konsole shell (there is a shortcut on the toolbar). From here, type "sdraw" to start drawing. When you are done, export your drawing as a .svg file (for example, test.svg).
- Next, run cam.py by typing "cam test.svg" (using your own filename). Within cam.py, write in a name for the toolpath that ends in .camm (for the sake of example, out.camm). Set the desired force and velocity in cam.py (more on this below). Then write the toolpath.
- Finally, to print to the vinyl cutter, type "cat out.camm > /dev/lp0" (again using your own filename).
Cutting A Circuitboard
- When you begin to use the vinyl cutter, the source of greatest potential frustration will probably be finding the proper settings for the force and velocity of the blade. Don't worry, you can do it.
- I have found that the far more important of these two variables is force. I have left velocity set to 2 units for all of my cutting.
- If you cannot separate your material from its backing, then your force is too low. If your piece is mangled, then your force is probably too high (or the blade might be dull). What you want to see is slight lifting of the material around corners.
- I have found that the force value must be within about 2 or 3 units. Fortunately, you can tell when the force is too high or too low, so the narrowing process is straightforward. If anyone finds good values for new materials, please let me know.
- You can also use the "Test" button on the vinyl cutter to make a test cut of a circle and a square.
- If it turns out that the blade is in fact dull, you can get another one from John or Professor Gershenfeld.
- The material to use is the roll of copper found by the vinyl cutter. Load as sheet of it as you would any other material.
- Make sure that your file in cam.py includes a box around your circuitboard for easier removal from the copper. Then print your file as above. I found the process to work with a force of 53 and a velocity of 2 with a new blade. Of course, as the blade dulls, these values might shift slightly. Mine should at least give you a starting point.
- Once you have your design cut, use the tweezers to lift the corner of your design a little bit off of the backing. The put the transfer tape on the copper. Don't press it too hard--you don't need to and you don't want to set the pressure-sensitive adhesive. Starting from the corner that you lifted with the tweezers, pull off the copper. Pull vertically, as you want to get everything. Weeding comes later.
- Now transfer the copper to the glossy side of the epoxy film, also found near the vinyl cutter. This is where your set the pressure-sensitive adhesive. The tweezers work well for this part. Use the long flat section to really press the transfer tape, copper, and epoxy film. Press really, really hard, and make sure to get the whole surface. When you pull off the transfer tape, the copper will stick to the epoxy film.
- At this point, you should have the copper rectangle, with your circuitboard cut in it, stuck to the epoxy film. Using the tweezers, carefully remove the excess copper. It is at this point that you pull horizontally, within the plane of the board, to keep everything from coming up. If you are patient, you will end up with a circuitboard on a piece of epoxy film without a lot of difficulty. I got my hello board on the first try, so if you are having trouble at some step, let me know and I will see what is going wrong.
- An easy and convenient substrate is phenolic, which can be found beside the vinyl cutter and can be cut with scissors. The epoxy film can be soldered on, and since it has a sticky backing, you can apply it to whatever you choose.