Engraving Dog Tags with SVG Files
This tutorial shows you how to use Inkscape to turn a hand drawing, clipart, or typed text into an SVG file you can engrave onto a dog tag. We’ll be using Inkscape, a free graphics application. If you have access to Adobe Illustrator, you can use a similar workflow.
Engraving anodized aluminum dog tags is a fun and fast project. By milling away the colored anodized coating on the metal, the shiny raw aluminum underneath is revealed. The contrast between the colored coating and the raw metal looks great, and this project requires very little setup and milling time to achieve a finished product.
Tools, Materials, and Files
- Othermill or Othermill Pro
- Engraving tool, 80° A 30° engraving tool would also work.
- Computer with our software installed
- Nitto tape, high-strength, double-sided Double-sided Scotch tape is not strong enough to reliably hold the dog tag in place.
- Digital calipers
Files to Download
- SVG file of dog tag template
- Printable PDF of dog tag template
- SVG file of finished file used in this example
Step 1: Create Your Design
As mentioned, we’ll be using Inkscape throughout this tutorial. If you’re new to Inkscape, check out their online tutorials.
Inkscape Tips: Inkscape is free and can be downloaded here. If you’re a Mac user, all keyboard shortcuts on Inkscape use Ctrl instead of the CMD button. For example, Ctrl+S saves your file, not CMD+S. To learn more about the nuances of turning an image into a vector path, check out Inkscape’s tutorial on tracing bitmaps.
Now let’s start creating the design to etch onto our dog tags. There are three ways you can create your artwork:
1. Find clipart online.
Search for black and white clipart. Simple designs are the best. Avoid thin lines. Keep in mind that engraving tools will slightly round out any sharp inner corners. The slight rounding is not a problem, as it will usually look fine, but it’s worth keeping in mind that sharp inner corners in your design won’t come out exactly as drawn.
2. Design in Inkscape.
Type text or draw shapes.
3. Draw your design by hand.
Use a thick black marker, like a Sharpie, on white paper. Keep your design simple and bold. Take a photo of your drawing and transfer it to your computer.
Below is an example that includes designs from each of these methods. Instead of finding clipart online, we found an image on a website and took a screenshot of it.
Step 2: Lay Out your Design in Inkscape
Now it’s time to open Inkscape on your computer. When Inkscape opens, it automatically creates a new document. When you save this document, Inkscape’s default is to save it as an SVG file. This is great, since an SVG is the file type we want!
Even easier than creating your own document, you can download and use this template. This template is an SVG we created that is all set up for your dog tag design. To use this template, download it, open Inkscape, click File > Open, and select the file. Now you should see the template open and ready for you to add your design!
Set the Canvas Dimensions
If you’re using the SVG template mentioned previously, you don’t need to set the dimensions of your Inkscape canvas. If you start out with a blank document in Inkscape, here are the steps to make it ready for your dog tag design.
Change the Canvas size to match the size of the dog tag. Go to File > Document Properties, and in the Custom Size window, change the units to inches (in). Set the width to 1.950” and the height to 1.125”. When you save the file, make sure it’s saved as an SVG.
Another option is to print out the PDF template onto a 8.5x11” piece of paper, grab a marker, and draw your design directly onto the paper.
Import the Design
- If you’re using a photo of a drawing or clipart you found online, bring your design into Inkscape by clicking File > Import.
- Use the Select and Transform tool to select, move, and scale objects.
- Use the Text Tool to add text.
- The dog tag has a hole on the left. Make sure your design isn’t located over this hole.
Step 3: Turn Your Bitmap Design into Vector Paths
The next step is to turn your bitmap designs into vector paths that the milling machine can then follow to mill your design.
Convert Photos of Drawings or Clipart into Paths
Click on the image, then select Path > Trace Bitmap.
Click the box next to Live Preview, and adjust the Threshold settings until the preview looks best and contains the level of detail you’d like. Click OK. Then click the red circle in the upper left of the window to close the window. You can always try again if you don’t like the first results.
The new vector path you just created with the Trace Bitmap feature will now be in front of the original image. Next, delete the original image: Click on the vector image and move it to the side, and then click on the original image and click the delete key on your keyboard. Now you’re left with just the vector path. Using the Edit Paths By Nodes tool, click on the vector path to confirm it’s now a collection of vector paths.
You should see lots of little gray squares that represent nodes of the vector. If you don’t see these little gray squares, something went wrong, and you should go back and try using the Trace Bitmap option again.
Convert Typed Text into Paths
Select the text, click Path > Object To Path. That’s it! Now your text has been turned into paths that the milling machine can follow.
Convert Shapes Made in Inkscape into Paths
If you create shapes, like a square or circle, there’s nothing else you need to do in order to turn those shapes into paths the milling machine can follow. Just save your file, and it’s ready to open in the mill’s operating software.
Step 4: Fine-Tune Your Layout
Adjust the size and layout of your design until you like the way it looks. To adjust the size, click on the Select and Transform tool (it looks like a black arrow), then click on one of the arrows that surround the object you want to shrink or enlarge. If you hold the control key, the proportions will stay locked as you change the object’s size.
If you’re using our Inkscape template, the lines that show you the shape of the dog tag are only 0.001” wide. When the file is loaded into the software that runs your machine, a preview will show the 0.001” lines with red warnings. These red warnings mean the end mill you’ve selected (the 80° engraving tool, in this case) is too large to mill the line, and it won’t be milled.
In some instances, the red warnings are covering something you actually want to be milled. However, for the purposes of this tutorial, we’re okay with the red lines covering the dog tag shape because we don’t want these lines to be milled.
Make sure that everything showing in the software preview is something you want to be milled. Any shapes inside the outermost shape of your SVG will be engraved. Engraving means that the engraving tool will etch a small amount off the top of your material. Click Files > Save As, name your file, and save as an SVG file.
Step 5: Set Up Your Material
Plug the USB cable into the back of the machine and to the USB port on your computer. Turn on the machine.
The first thing our software will do is prompt you to “home” the machine. Homing the machine means the moving parts of the mill, called the carriages, will go to their starting point. Homing the machine moves all the carriages to the origin and tells the software where the parts of the machine are located in space. Without homing, the software wouldn’t know where the parts of the mill are located, and therefore, it wouldn’t be able to start milling your dog tag.
Physically load your 80° engraving tool into the mill. The engraving tool is sometimes referred to as an engraving bit or end mill. Read this post for a primer on cutting tools and to learn the difference between end mills and bits. If you haven’t done this before, refer to the Inserting and Locating a Tool guide.
Next to Tool, click the Change button, select “80° Engraving Tool,” click Continue, verify tool position (it should be above an empty area of the spoilboard of the machine), and click Locate Tool. The tool will lower until it touches the spoilboard, pause, then retract upwards. Now the software knows where the engraving tool is located in space.
Using digital calipers, measure the dimensions of your dog tag. Width is X, height is Y, and thickness is Z. Enter these values for the Material Size.
You’ll be using double-sided tape to attach the dog tag to the spoilboard of your machine. Use digital calipers to measure the thickness (Z) of the tape. Enter this measurement as the value for Material Placement (Z).
Note: Most of the time when errors occur in this project, it’s due to the thickness measurements being incorrect, so take your time with this step!
Apply a single layer of tape to the bottom of the dog tag. Cover as much surface area as you can, but make sure not to let the tape overlap or wrinkle. If tape overlaps, it will make the dog tag stick up higher than the software expects, which can cause rough cuts or even damage the engraving tool.
Place the dog tag on the spoilboard as shown in the photo below. Be careful to align it as closely as possible with the front left corner of the spoilboard.
Note: Spoilboards are often considered to be “sacrificial,” meaning it’s okay if the end mill accidentally mills into it because it can always be made smooth again in the future. You can read more about the spoilboard in our Dimensions and Diagrams Guide.
Step 6: Set Up the SVG File in the Mill’s Software
Now we’re ready to bring our SVG file into the software.
- In the software, under Plans, Click “Open Files,” and select the SVG you just saved in Inkscape.
When your file is opened, both Engraving and Cutout will automatically be selected. (When selected, they’re darker gray. When deselected, they’re lighter gray.) Click Cutout to deselect it. Now only Engraving is selected, which is exactly what we want.
Set the Engraving Depth to 0.003 inches. This means that the engraving tool will remove three thousandths of an inch of material off the surface of the dog tag.
Under Milling Tools, select “80° Engraving Tool.”
Next, in the Advanced settings section, change the “Scale From” value from Document Content to Document Bounds. The Document Bounds option aligns your SVG design as it was on the Inkscape Canvas. You’ll now see a box outline appear in the preview, which is the outline of the Canvas from your Inkscape design file.
The software will now render a preview. Anything covered in red will not be milled, as the red warnings indicate that the end mill selected is too large to mill that area. Everything else visible will be milled. If something looks wrong, go back through steps 5 and 6, and verify your settings.
The image below shows what your completed setup should look like. Check each setting and make sure this image matches what your milling software screen looks like. The only things that might be different are the Material Size and Material Placement sections because you’ve entered specific values for the dog tag you measured with digital calipers.
If you’d like to print this diagram, download the PDF version here!
Step 7: Mill Your Design
At this point, we’ve loaded the 80° engraving tool, entered dog tag and tape measurement values, attached the dog tag to the spoilboard, opened the SVG file, deselected Cutout, set the engraving depth to 0.003”, selected the 80° engraving tool, changed the “Scale From” value to Document Bounds, and looked at the preview to verify the settings.
When you’re happy with how everything looks, place all four windows on the mill. Now you’re ready to click “Start Milling” and watch the milling machine cut your dog tag!
Troubleshooting: What Usually Goes Wrong
To help with troubleshooting, here are a few simple rules explaining how our software treats SVG files.
The mill engraved too deeply or too shallow.
Most of the time when errors occur in this project, it’s due to the thickness measurements being off. So take your time measuring. Read more in our Setting Up Your Material Guide. You also might want to try reducing or increasing the Engraving Depth value.
The machine will turn on, but the “Start Milling” is grayed out.
All of our milling machines come with the Emergency Stop button engaged. If you’re firing up your machine for the first time, look for the warning box in the software indicating that your E-Stop is on. If your E-Stop is engaged, push in and twist the red button on the side of the machine. Once the E-stop is off, make sure that all four windows are in place. With the E-stop off and windows in place, the machine should make a few start-up beeps, and then you’ll be able to press “Start Milling.”
The software preview doesn’t look like my design.
Our software will render the last saved version of the SVG, so if the preview doesn’t look quite right, try going to back to Inkscape and saving the file again. Then refresh or reload the file into the software.
It cut a hole through my dog tag outside my design.
The outermost shape on your SVG file will be considered as the outline of your file, and you’re given a “Cutout” option if you want to mill all the way through your material and give your engraving a unique shape. (In the advanced settings, you can choose to cut out your design outside of this outline, inside the outline, or in the middle of the outline.) The end mill will cut through the entire thickness of the material during a cutout, so cutouts require a flat end mill. An engraving tool won’t work for cutouts.
It won’t mill my line.
Strokes are milled as lines, but only if the strokes are as wide as the width of your engraving tool or end mill. For instance, the 80° engraving tool used in this tutorial has a cutting diameter of 0.005”, and can therefore mill lines that have a stroke of 0.005” or wider. If your line isn’t being milled, the software will alert you in the preview by making the lines red. To enable the line to be milled, either make the stroke wider or try using a smaller end mill.Once you make this change, look at the preview again. If the stroke is now wide enough for the engraving tool to mill, then there will be no red lines in the preview.