The Othermill is an easy-to-use desktop CNC mill that can fabricate amazing things out a variety of materials, including wood and metal. Etching printed circuit boards (PCBs) for electronics is one task it handles particularly well. In this tutorial, we show you how to make a light-up circuit board that displays the famous "Hello World" message. It's designed for Othermill beginners, and we walk you through all the steps.
The rack that extends from the side of the finished project even gives you a charming yet handy way to store the hardware included with your Othermill. It's adorable and functional!
This tutorial covers:
- Using Otherplan with EAGLE circuit board files
- Making single-sided circuit boards out of FR-1 PCB blanks
- Using FR-1 as a structural building material
The Othermill comes with all the materials needed to complete this project — the only additional thing you'll need is a soldering iron and diagonal cutters.
Step 1: Materials, Tools, Files, and Skills
- Othermillincludes handy accessories like spindle wrenches and end mills
- Computer running Mac OS X, with Otherplan installed
- Soldering iron and solder
- Diagonal cutters for clipping wires
- Calipers to measure your board (optional). Calipers are available at most hardware stores, are easy to use, and can range in price from inexpensive to absolutely shocking. They're useful for very tiny, accurate measurements, more so than a ruler or by eyeball.
- Helping hands tool aka "third hand," to hold your circuit board in place while soldering (optional)
MATERIALS (all included in the Othermill's Hello World Kit, which comes with the mill)
- Single-sided FR-1 printed circuit board blank
- 47-ohm resistors (2)
- LEDs (2)
- Coin cell battery, 3-volt, CR2032
- Coin cell battery holder
- Double-sided sticky tape
- Hello_World_V3.brd attached in this step
- Basic understanding of how a simple electrical circuit works
- Basic soldering skills
- Basic understanding of what milling is
- OR the willingness to pick these skills up while you make this project. It might take a little longer, but if you've never done it before, you'll feel like you just invented fire!
Step 2: Set Up Otherplan and Your Othermill
Follow these steps to set up your mill. For a complete walkthrough of unboxing and setting up your mill for its first use, see our Getting Started guide.
- Make sure your mill is plugged in to a grounded electrical outlet.
- Connect the USB cable to the back of the Othermill and to your computer.
- Download and install Otherplan. To do this, click Download on the Otherplan webpage, double-click the .dmg file, and drag Otherplan to your Applications folder.
- Open Otherplan by double-clicking the icon in your computer's Applications folder.
- Turn on your Othermill by pushing the power button on the back of the machine and by twisting the red Emergency Stop button on the right side of the machine. The E-Stop button should be sticking out.
- Enjoy the mill's cheerful beeps that play during its startup sequence.
- In Otherplan, a dialogue will pop up that will ask you to "Start Homing" the machine. Homing tells the machine where it is in space and makes sure the position of the tool in the machine matches the position of the tool in the software. This ensures that all your cuts are exactly where you want them to be.
- Click theStart Homingbutton.
- The Othermill will go through its homing procedure, which will take a few seconds.
Step 3: Set Up Your File
- In Otherplan, clickImport Files and select the Hello_World_V3.brd file that you downloaded.
- You'll see a rendered version of the file appear on the machining bed in Otherplan, and the file name should appear on the right side of the screen with some options and buttons below.
- Click the Setup Material button and choose "Single Sided FR-1." "Standard" should be pre-selected from the Size pull-down menu, but if not, select it now.
- Click Continue to "Set Material Properties." Leave all the default values as they are, and click Done.
- On the right side of the screen, under Hello_World_V3.brd, there are options for selecting the Traces, Holes, and Outline.
- Click these buttons and notice how the rendering in Otherplan changes to show what parts of the file will be cut into the FR-1 board. Make sure all three buttons are selected (i.e., you are cutting all three: Traces, Holes and Outline).
- Right below this, there is a place to choose which tool you'll be cutting the board with. Select a 1/32" flat end mill (this should already be selected by default).
Your file is ready! Next comes the tool setup.
Step 4: Set Up Your Tool
- In the upper-right corner of the Otherplan window, click Set to set your tool. This will lower the z-carriage, making it easier to install an end mill, and it will also bring up a dialogue box to walk you through the tool-changing process.
In the dialogue box in Otherplan, select the tool you want to use (a 1/32'' flat end mill) and click Continue.
Remove the collet from your accessories kit if you haven't already installed it. The collet is the round device with a hole through it that holds your tool in the machine. Make sure the collet is snapped with the wide end in to the collet nut. Then screw the nut loosely back onto the spindle shaft.
Slide a 1/32" flat end mill into the collet all the way, and then use the two wrenches to tighten the collet nut onto the spindle. It doesn't have to be super tight, just snug plus a little bit.
Click Continue and the mill will position the tool over the bed. The tool should be in an unobstructed area, but if it isn't, use the x and y arrows to position it so it is.
You'll be instructed to make sure the tip of the tool is in the "safe zone," which is the area in front of the white piece of plastic that makes up the bottom of the x-carriage. The green rectangle in the Otherplan dialogue box illustrates this as well.
Click Locate. The mill will perform a tool touch-off, which sets the z position of the tool. After a successful touch-off, the mill will re-home itself. For an in-depth description of the tool touch-off sequence, see our Tool Location tutorial.
Step 5: Set Up Your Board on the Mill
Now it's time to position your FR-1 in the machine!
- Click the Loading button in the main Otherplan window. This will bring the bed of the mill forward.
- Cover the non-copper side of a single-sided FR-1 PCB blank with one layer of double-sided tape.
- Stick the board down to the bed of the mill so that the bottom left corner of the board just hangs over the edges of the bottom left corner of the aluminum bed.
- Click on the Home button to retract the bed to the home position.
Step 6: Cut Your Board
It's a good idea to stay close by your mill while it's cutting. Never leave a working mill unattended.
Grab whatever you need to get cozy with your Othermill for the next hour or so.
- Click the Start Cutting button inside the "Hello_World_V3" panel on the main screen of Otherplan. Watch as the mill cuts the traces, holes, and then outline of the file into the board.
- When the mill is finished, vacuum all the chips out and click the Loading button. Grab a cheese knife or a putty scraper and gently pry up the FR-1 board as well as the separated pieces that were cut from it.
- Clean the edges of your board with a Scotch-Brite pad and use a knife or engraving bit to clear out the slots.
Step 7: Add the Electronics
It's easier to solder on the electronic components before you assemble the pieces together, but it's helpful to understand how the structure fits together before you start soldering on the components. So fit the pieces together using the instructions in the photo below.
Use this to get a sense of where the LEDs, resistors, and battery holder go, and on which side they're mounted. Once you understand where they go, take apart the model and follow these photos to solder them:
The photo of the EAGLE board at the top of this step is also helpful for locating where the components should be attached.
Step 8: Assemble
Now that your parts are soldered, assemble your bit rack once more and solder it all together following these steps.
- Press-fit the sides onto the front piece just like you did before.
- Solder the copper tabs that overlap in the joints. There are two tabs to be soldered on each side. These joints not only hold the pieces together, but they also complete the circuit. This allows current to flow from the battery on the left side, through the text on the front, all the way to the LEDs on the right side.
- Next, slide the bottom piece of the rack into the bottom slot on the right side and solder the joint.
- Do the same for the top piece of the rack.
- Use a piece of double-sided tape to stick the rack base underneath the bottom of the rack.
- Now that the structure is complete, gently bend the LEDs so they point towards the back of the front piece.
Continue on to the next step to see if the circuit works!
Step 9: Use It!
Slip the battery into the holder so that the flat top of the battery (with the text on it) faces inside. The LEDs should now be on. Fill up the rack with the hardware and tools you got in your accessories kit and use it all day every day!
Congratulations, you've just made your first project on the Othermill!
Have questions? Email us at firstname.lastname@example.org and we'll be happy to help!
And as always, for more information about new kits, store goodies, stories we tell, and machine updates, check us out at othermachine.co!