Definitions and Basic Explanations
Vector vs Raster
If you need to cut or route something, be it on a vinyl cutter, CNC plasma cutter, laser cutter, or CNC mill/router, the first step is always having a valid vector artwork for your job. Just because you saved your file as a PDF, EPS, or whatever vector format we list here, that doesn't mean you've actually got valid vectors that we can use to cut your job. A scanned drawing, an artistic rendering, or any other representation of your designs in raster format (meaning it's made up of pixels) won't work for generating tool paths for the machines.
Your designs need to be made up of points and lines and they need to be created in software that can create vector based files, like CAD or vector based drawing software. These programs would include (but are definitely not limited to) Adobe Illustrator, AutoCAD, CorelDraw, LibreCAD, Inkscape. LibreCAD and Inkscape are both free programs that are compatible with Windows, Linux, and Mac OSes, so they're a good start if you're just getting started and don't want to spend money on a CAD or drawing program.
The one exception to requiring vector artwork is raster cutting with the laser cutter. Jump down to the end of this page for more info on that.
Kerf is the amount of material that the machine removes when cutting your design. For some machines it's virtually zero, like the vinyl cutter, which just cuts the material with a knife and doesn't remove anything. For the laser cutter and plasma cutter, material is vaporized away during cutting, removing a small amount of material in the cut line.
The plasma cutter and laser cutters cut on the lines of your artwork, so you must compensate for the kerf in your design if a high degree of mechanical accuracy is important. Kerf for the laser cutter is typically 0.007"-0.01" in plastics, wood, and other hard materials and 0.02"-0.05" in foam and other soft materials (sometimes more if cutting pieces in thicknesses over 1"). The plasma cutter's kerf is typically 0.05"-0.07" depending on material
For the CNC router or mill, the kerf is the size of the bit used and will be compensated for in software. These bits can't fit effectively into inside corners and other features of designs that might be too small, so tooling selection is important.
General File Preparation Tips
- Don't include hidden layers or any other geometry or features other than what you want cut or etched (even hidden ones).
- Use different colored lines to indicate cut versus etch lines (eg. blue for cut, red for etch) if needed.
- If your design includes text of any kind, make sure to embed the fonts, or better yet convert them to outlines. If you're using any type of CAD make sure the text is exploded into lines.
We have a number of materials in stock in the correct blanks sizes for our machines, so we generally prefer supplying materials for jobs but we're happy to use your material as well. If you are supplying the material for a job, verify with us first that the material will work for the process you choose. For instance, PVC plastic can not be cut on the laser cutter due to toxic fumes, galvanized metals aren't suitable for plasma cutting, soft aluminum doesn't machine well in the CNC router, etc. You are responsible for providing details on the materials you source so we can be sure that they will work for your application and that they will not damage the machine.
All supplied materials must be as flat as possible for proper machine operation.
Verify the blank size required for each machine before purchasing materials and let us know if we'll need to cut materials down.
Blank Sizes and Margins for Different Machines
Different machines have different cutting areas and different margin requirements.
Our smaller laser cutters have addressable cutting areas of 12"x24". They work very fast and are great for detailed etching and for cutting thin materials like paper. These machines generally require 1/8" margin around the border and 1/16" margin between parts (unless those parts are sharing lines).
Our larger laser cutters have an addressable cutting area of 34"x44". They're great for cutting thick materials and for deep etching jobs. These machines generally require 1/4" margin around the border and 1/8" margin between parts (unless those parts are sharing lines).
The plasma cutter has an addressable area of 24"x24" and generally requires a 1/2" margin and 1/8" between parts. There should also be sufficient free space on a sheet layout to allow for clamping of the sheet in at least 2 places. Small features need to be at least 1/16" apart to prevent melting. Tightly packed small features can cause warping of the material being cut, so care should be taken to distribute these parts throughout a layout if possible.
The large format CNC router has an addressable area of 78"x120". The margins and distance between parts is dependent on the tooling used and the hold down requirements for your work piece. Consult us when setting up a cutting layout for general guidance.
Large and Multi-material Jobs
If using multiple materials (or different thicknesses of materials) and multiple pages or material blank sizes, break up the job into individual files, one for each blank, material, and thickness of material. If certain sheets need to be cut multiple times, indicate that in the file name as well.
Specific File Type Tips
We use a variety of software tools to prepare your provided designs before they get cut by our machines. Many of them do not support bleeding edge features in the various drawing packages out there, but almost all support the common vector formats like DXF and EPS. Here's some tips for ensuring we can open and use your files.
DXF files are a common file format for mechanical drawings, mostly exported from CAD software.
- Please export DXF files in AutoCAD 2004 or older format to ensure compatibility with all our machines.
- In many cases this format will not preserve fills.
- If you have text in your designs, make sure it have been converted to outlines if you need to preserve the exact representations of the text.
- This is the preferred format for the CNC plasma cutter.
- Units need to be in inches or mm and please let us know which when sending us files.
Use postscript level 2 if the software you're exporting from supports it.
- Depending on the export options chosen, sometimes SVGs can lose a little bit of accuracy, so open your exported SVG and inspect it before submission.
- Scaling can also be affected when exporting, so verify scaling (preferably in a different software package from the one you created the artwork in) before submission.
- Inkscape SVGs do not import well unless you have saved them as plain SVGs, but if you generated your artwork in Inkscapse we generally like to work from the original Inkscape SVG (see Inkscape below).
PDF documents generally work well, but require us to do a few conversion steps to use in some cases and we sometimes need to verify scaling. They're great for proofs though (especially stuff with text), so if you want to send along a PDF with a copy of the design in another format that can be helpful for us.
If working in Illustrator, provide the original Illustrator files. Illustrator exports generally don't work well with non-Adobe software. We have the latest version of Illustrator CC and can open these files just fine and export what we need from there.
CorelDraw generally works well for prep for cutting and we use it to draft and preform pre-flight checks on a lot of our jobs. Export in version X5 (15, not 5) or older to make sure we can open your files.
If you send us an Inkscape SVG, please indicate that it was made in Inkscape. Inkscape SVGs don't import well, but we can open your file in Inkscape and export it as something we can import properly.
One thing that laser cutters can do that's a little unique to CNC machines is the ability to function a little like a printer and scan a surface, pulsing the laser as it goes, to burn an image into the surface.
Good Raster Images
Good images for laser rastering are high contrast, black and white only images (gray scale images do not work particularly well in a number of materials).
Lossy vs Lossless Compression
Images should be in a lossless format if possible. JPEGs are great, but compression artifacts will often show up in etchings. Use PNG or GIF formats if you don't want to introduce image artifacts when preparing raster graphics for etching.
Our smaller cutters can put down images at 1200, 600, and 300 DPI, while our large cutter is generally limited to about 250 DPI. The laser can raster images less than this DPI, but we don't suggest using images below 150 DPI.
Optimizing for Time
Raster etching can take a lot of time, which can make it expensive. The laser moves very fast in the direction that it's scanning (the x-axis in the case of both of our cutters) but slow in the other axis. If you can lay out the elements you need to etch in a straight line on the fast axis, you can substantially reduce the amount of time.