Chinese paper dragon cut-out
It’s best to start with clean black-and-white artwork. The artwork should ideally be very high-contrast, with what you want to make in black, and everything else white. The cleaner the input, the easier it is to do. You can trace photographs, and messy color artwork and such also, but the results may not be so good, and probably will require more work on your part.
Following is the basic process:
- Take a picture of what you need (or scan it in with a scanner), as you will need the artwork in digital format . For this picture, I used a three megapixel camera.
- Load the picture into your image tracing software (sometimes called “raster to vector” software). In this example, I am using OMAX Intelli-TRACE®.
Image loaded in OMAX Intelli-Trace
- Crop the image so only the portion you want will be traced. This may not be necessary if you scanned in just the part of the image you want.
Crop the area you want to trace
- If necessary, adjust image and remove noise.
Adjust the image
- The software traces the edges of high contrast automatically for you.
There are a lot of third party image-tracing software packages out there such as Adobe Streamline, Cutting Shop from Arbor Images, and WinTopo. For the above example, I show OMAX Layout, since that’s software I’m involved in writing.
Another package that I found gives excellent results is a program called “Gems” from a company called CadCraft in Sweden. This is a $2500.00 package that includes CAD / CAM / Nesting / Image Tracing, and other nice tools useful for waterjet users. I have not had much of a chance to use Cutting Shop from Arbor Images, but I have heard good things about it as well. It’s also a little bit cheaper at around $900 or so.
Adobe Streamline is significantly cheaper at $150.00, but does not always produce such good results, and it is strictly for image scanning and tracing, and no longer supported by Adobe. There are also a few free packages out there on the Internet that give mixed results.
Some things to look for when shopping for raster to vector software:
- How easy are the results obtained
- How well does the software deal with noisy images, or low resolution images
- How good is the output? Does it contain “zillions of lines” and lots of garbage that will need to be cleaned up by hand, or does it give nice smooth and clean output suitable for a tool path?
- What file formats can it accept as input?
- Try before you buy. If they don’t give you a free trial where you can try it on your own files, then take that as a red flag.
Once the image was converted to vector format, I clicked on “Finished” to bring it into my CAD/CAM software, so that I could turn it into a tool path.
With nearly 1000 holes, it took the computer two to three minutes to calculate the above tool path sequence, considering things such as collision avoidance. That said, though, automatic tool path planning is rarely perfect, and it’s a good idea to check the results and make corrections “by hand”, if you see the that the computer decided to do anything stupid. Also, since this part started out as a photograph, it’s a good idea to spend some time making sure it’s doing exactly what you want.