Using Rhino with Epilog Laser Cutters

With an Epilog laser driver, Rhino can directly control the Epilog laser functions: vector and raster modes and laser speeds and feeds. The laser driver is like a Windows printer driver. Once installed, it will appear in the list of printers available in Rhino and Windows in general.

The Epilog can print in a raster, vector, or combined mode. The Epilog Owner's Manual covers the reasons you may want to run projects in a raster or vector cutting mode. Normally the printer driver should be set to Combined mode, which allows control of both vector and raster operations.

Some Rhino objects (text, solid hatches, bitmap backgrounds, and shaded views) will automatically cut in Raster mode.

Other objects (curves, wireframes, and all non-solid hatch patterns) can be printed in either Vector or Raster modes.

To cut text in Vector mode, create the text as curves or reduce text to curves with the Explode command.

Once set up, control raster or vector cutting of lines by setting their lineweight. Set lineweight in Rhino as a layer or object property. This example shows lineweights assigned to layers.

The Default lineweight in Rhino will plot as a vector line on the cutter.

• In the Printer Properties, set the Piece Size.

1. Draw a rectangle the size of the stock size.
2. Move the rectangle around your art work.
3. In the Print Setup dialog box, place the print window at one corner of the rectangle to locate the position on the stock.
4. Set the Scale to 1:1.
5. Under View, select Window.
6. Click the Move button.
7. Use object snaps to move the print window to the edge of the border rectangle.

Drawing the rectangle of the outside of the art work lets you consistently place the print in the same position on the stock.

This method practically guarantees a perfect placement of the file to be cut relative to the material.

1. Create a laser template in Rhino by opening a blank file and drawing a rectangle the exact size of the cutting table with the origin on the upper left corner. Set the print width of this rectangle to No Print and lock it. Place it on a Table layer and lock the layer as well. Then save this file as your laser template.
2. In the Epilog printer properties, be sure to enter the exact table size under Piece Size.
3. In the Rhino print dialog, make sure View is set to Extents. Scale is set 1:1. All margins set to 0. Position set to Offset from Upper Left (Centered unchecked) and Offset values both 0.

The effect of the above is to lock the print area to the same size and placement as the laser table itself. It will never accidentally move. You will never have to adjust the print window.

1. Now, when you draw or import your geometry, place it inside the rectangle in your laser template at the same location as it will be placed on the table of the machine. I recommend placing it in the upper left corner (machine origin), which corresponds to the edges of the guide rulers.
2. Place your piece of material at the same location in the machine (upper left corner against the guide rulers).
3. Press Print. Make sure your settings are as above and that you have also set the speed/power correctly for the material, then Go!

Rhino has a sophisticated order that it prints objects to the laser that is is programmed into Rhino. The normal draw order is:

1. LockedHatches
2. LockedCurves
3. LockedSurfaces
4. LockedWires
5. LockedPoints
6. LockedPointClouds
7. LockedAnnotations
8. LockedTextDots
9. NormalSurfaces
10. NormalWires
11. NormalHatches
12. NormalCurves
13. NormalPoints
14. NormalPointClouds
15. NormalAnnotations
16. Grips
17. TransparentObjects
18. NormalTextDots

Note: The Epilog driver will automatically print raster objects before any vector lines.

To control the strength and speed of the raster and vector lines of the laser, use the raster and vector controls on the general tab of the Legend printer driver controls in the Epilog driver.

Lines with lineweights thinner than .175mm (.007 inches) will plot as vector. Lines with lineweights over .175 mm (.007 inches) will plot as raster. In vector-only cutting modes, lineweights greater than the above threshold are ignored!

If you need more control of strength and speed of the laser, map individual colored lines in Rhino to different strength and speed of laser within a single print. See the Advanced Laser projects section under Color Mapping Strength and Speed of Laser.

Note: Be careful when switching between raster and vector modes. On many materials, switching an object from raster to vector can greatly effect the material. Simply changing a lineweight can change a vector cut to a raster cut.

Simple multipass printing may be necessary to cut completely through the material or to control the speed and raster/vector mode. Time constraints may also require you to stop a session and restart it later.

Use Epilog's advanced Color Mapping mode to set the order, strength, and speed of the job based on the color of the lines in the plot.

Color mapping works on vector lines only. This means only lineweights thinner than .175mm (.007 inches) can be controlled this way. Thicker lines are plotted before any of the color-mapped lines and are controlled by the general raster setting on the General tab.

When color mapping is used, the laser always cuts the colors in the color list first. If there are any other lines in the image, they aree cut after the assigned colors, and they use the Vector Settings from the General tab.

The Epilog manual mentions the difficulty of using the 3D Engraving mode on the Advanced tab, “Creating a 3D image that will look good after engraving can be very difficult to achieve because most software packages do not provide the necessary tools to take complex objects and blend them in more than one direction from dark to light (or, visa versa).” Rhino, however, can create these models without resorting to the 3D Engraving Raster mode.