Full Spectrum Hobby Laser
Harold is the laser closest to the door. Washington is the laser closest to the projection screen.
File Formats
We recommend SVGs because we use Inkscape in the lab. An SVG is a scalable vector graphic, and the vector is where the laser will cut or engrave. You can have a JPG, GIF, PNG, or BMP etched onto something, but the laser does not produce color, and the image will be reduced to a binary black or white, as in the picture below:
Warnings
From the Manual: Never cut any PVC or vinyl on the Full Spectrum 40W/45W CO2 Hobby Laser (5th gen).
About
New 40W/45W CO2 Hobby Laser (5th gen: 20"x12"+Removable Floor) product page
Tips
Keychain keyhole size: .180"
For mirrored acrylic, place mirror face down (laser will reflect otherwise) and reverse image (so it shows up correctly).
Depending on the material, you may need an additional vector pass (vector = cut). If it looks like the cut object is not loose, raise the lid and apply pressure to the object. Try not to slide it on the honeycomb. If it's not loose, repeat the vector pass. Your project is saved!
Templates
CPL Keychain
"Your Name" Tab
"Your Name" Dogtag
Settings
This spreadsheet is linked from a thread in the Full Spectrum Forums: Spreadsheet. Consider this a point for comparison only.
The spreadsheet below is what we have done in the lab. You can add to it by clicking here.
Examples
This is white acrylic with a layer of green. There are two problems here: scorch marks around the attempted vector, and the fact that the vectoring was unsuccessful -- meaning the keychains aren't removable and wouldn't pop out of the acrylic sheet.
That experience led to experimenting with different settings, and recording the settings on unsuccessful vectors (you can tell we were experimenting because we skipped the rastering and just vectored smaller shapes). A successful cut was about 20% Speed and 80% Power, though the perimeter was a little sticky feeling. Also note that during the rastering process in the photo below, the image is not aligned! How does that happen? The head of the laser has a cord that we suspect slid onto the acrylic; the ensuing friction shifted the acrylic during the process.
The object on the left was the first attempt with the mirrored acrylic. Inventable's Edward suggested turning down the raster and the result is the object on the right. Much cleaner! When using the mirrored acrylic, you must cut on the "back side", that is, not the reflective side. So you'll put it mirror-side or face-side down. That requires you to mirror your image. Both Inkscape and Retina Engrave (the laser cutter print dialog) make this easy to do. You may want to do it in Inkscape, however. I had a mishap where I mirrored the image in Retina Engrave, but it did not mirror the keychain's position, so it was off center.
This was a really simple, fun attempt inspired by a design one of our staff members wanted to try. Although this is close, it's not identical, so experiments will continue on the 3D printer.
Rastering Mayor Harold Washington:
Other Resources
Pololu, an online delivery service, has an exceptionally informative set of instructions that may also be useful to new makerspaces.
Videos & Tutorials
2007 Laser Cutter Contest, Instructables, robot
Christmas Snowflakes Decorations with laser cutter!, Instructables
cutting a stencil on the laser cutter, Instructables