Laser

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You must be properly trained and membership-level qualified to use the laser!

About

Our members pitched in and bought a laser for the space! It's a 45W Full Spectrum H-Series 20x12Desktop CO2 Laser, and can do raster engraving and vector cutting. It has a honeycomb cutting table surface, exhaust vent, and a removable bottom for cutting larger things. The laser tube is water cooled from the blue bucket under the table. With the printer driver, anything that can be printed can be laser'd, but it a bit easier to laser things in PDF or dxf format

Lasering area: 20” x 12”

Design Software

The computer next to the laser cutter is configured for member use and lasering. Here's a list of the installed design software:

  • Inkscape
  • Draftsight
  • FSL RetinaEngrave 3D drivers

Basics of laser cutting

The laser cutter at Hive76 is a sophisticated CNC machine that use focused infrared lasers to vaporize materials based on your instructions. There are three operations that this vaporization can be described as: raster engraving, vector cutting, and third that has aspects those combined called vector scoring.

Raster engraving

In this operation, the laser beam travels over the entire area of your shape. Raster engraving is a marking operation used for decoration or information. The laser will quickly vaporize a thin debossing into the top surface of the material. The depth of this debossing can be adjusted roughly with different speeds. This operation requires the area to be filled with pure black color. If your design has fuzzy edges, or gray areas, those will be interpreted as a halftone in the laser software. This way it is possible to engrave grayscale images. Raster engraving is useful for marking text onto a design. It can also expose a different color in some specially designed layered materials. The time required for raster engraving is dependent on the overall area the laser must travel to reach your black-filled designs. Raster engraving is the only operation that can be used with bitmap images such as jpegs, pngs, gifs, or bmps. All color will be reduced to a black and white halftone in the software, so make your own grayscale first.

Vector cutting

Vector cutting is an operation that can cut your material all the way through. This operation is used for making specific shapes and cutting material to size. Here the laser slowly travels along a thin line in your design while vaporizing all the material along its path. This operation requires more than an image. We need to program the laser with vector lines. If you use CAD or Illustrator you are familiar with vectors. Instead of pixels describing an image, vectors are mathematical formulas that describe the shape of a line. This makes them perfectly scalable and allows us to program a robot to carefully follow such lines. For vector cutting your lines need to be very distinct from any raster engraving art. Vector cutting lines must be pure red in color and include a stroke that is as thin as possible; 0.1 pt will work in most cases. The laser software is programmed to recognize these lines and the laser will follow them exactly. Vector cutting is like cutting with a saw in that some material will be removed during the process. This is called the kerf and for lasers generally measures .005” but will vary based on your material thickness. If you need exact cuts that account for kerf, try a test cut with your material first and measure your results. In the sample above there are horizontal pylons connecting the counters in the middle of some letters. Keep in mind that vector cutting can completely separate your material into pieces, and some of those pieces (like the counter inside an “O”) you may want to retain. This operation adds time to your job based on the length of all your cut paths.

Vector scoring

This operation is halfway between raster engraving and vector scoring. Like raster engraving, it is used to mark your material, but it is programmed like vector scoring. In this operation, the laser travels along the vector line you designed, but does so quickly just removing a small amount of material from the surface. To design for this operation, use a thin line of 0.1 pt or less but with a pure blue stroke color. This color will differentiate your vector scoring designs in the laser software. Vector scoring is a faster way to make marks on your material that are less dense than raster engraving. A good example could be a grid of thin boxes denoting windows on a facade or building footprints. Like vector cutting, this operation adds time to your job based on the length of all your vector scoring paths.