We're happy to work from whatever you send us - scans of paper drawings, full-size cardboard templates, napkin sketches, "paint" sketches - we'll do whatever is needed, perhaps at some additional cost.
Your best value for waterjet parts is had by sending us clean vector art satisfying the CAD guidelines laid out below, as well as the general waterjet design guidelines.
Clean vector CAD:
Clean vector art means the perimeter of each part, and the outline of each hole or other interior cutout, is represented as a single closed path consisting of lines and arcs, with no gaps, no unconnected loose ends, no 3-way intersections, no hidden duplicates. Each feature starts at a point and follows a sequence of connected lines and arcs that return to the starting point. Endpoints have to actually touch - not just appear to.
With certain entry-level CAD (Google Sketchup is one), when you save a DXF or other industry CAD format, polylines are output instead of arcs - circles represented as many-sided polygons, drawn as dozens or hundreds of short straight lines. This is a common limitation of certain software intended more for creating drawings for print than CAD files for computer-driven manufacturing. We can draw over the polylines with arcs and circles, but it's not automatic, and may add to your cost.
Drawings files can be Solidworks, DXF, IGES, STEP, PDF, AI, EPS - almost any standard format so long as it actually contains clean vector information.
For waterjet parts, it doesn't matter whether it's a 2D or 3D model - if 3D, we'll check features and extract a flat pattern for cutting.
In general if you're modeling in 3D CAD, please send us your raw CAD in its native format - not a "print" or an interchange format. It's always helpful to include a PDF print with your CAD however, as the print may answer questions about material, tolerances, finish, 2nd operations and such.
If we're bending sheet metal, it's particularly helpful to send parts modeled using sheet metal CAD features such as in Solidworks, as this enables us to verify and/or adjust bend geometry to match our tooling.
Raster to vector/scan conversion:
Waterjet cutting is inherently a vector process - lines and arcs describing part features. If your art started as a hand drawing, photo, a scan of a template etc., its first digital representation is as a raster bitmap - pixels suitable for screen display and printing, but not for cutting. Something must analyze the scan and extract usable vector information.
Unfortunately most scan conversion software, even in the best packages, fall far short of being "automatic". Free-form curves with varying radii become a mix of smooth curves and jaggies. Round features become sharp points. Projects with complex designs in some cases require hours to trace over with smooth features. Often it works best for us to do this for you - it's what we do. This is mentioned here because some would prefer to do this themselves.
Drawings originating as scan conversions, and drawings that have been significantly scaled up or down in size, often have features too small, or with detail too fine to cut. With the .03" kerf, your scaled-down or autotraced drawing may show a cutout only .015" wide, that simply can't be cut as drawn. Drawings are examined for detail that needs to be smoothed or removed.
Many fonts rendered in design software, such as Illustrator, while vector fonts strictly speaking, are engineered for print and screen display and fall far short of the "clean vector CAD" requirement. Fonts often have duplicate or overstruck components, that blend invisibly in print, but are not directly usable for waterjet or other machining.