The goal of this project is to develop a laser head for 3D printing or PCB manufacturing which uses a scanning prism and is easy to assemble.
The open-hardware fast high resolution LASER is demonstrated by the manufacturing of PCBs. PCB is desirable from a technical point of view as it is 2D which makes exposure errors easily detectable. Cyanotype paper is used as it can be developed with water. The current electronics also provide the possibility to cut a PCB with a spindle.
Specifications were determined from the proof of concept model by exposure onto a camera without lens and OpenCV
- wavelength: 405 nm
- rotation frequency: up to 21000 RPM, current 2400 RPM
- line speed: up to 34 meters per min @ 21000 RPM
- spot size FWHM: circular, 25 micrometers diameter
- cross scanner error: 40 micrometers (error orthogonal to scanline)
- stabilization accuracy scanning direction : 2.2 micrometers (disabling/enabling scanhead)
- jitter: 35 microns (error parallel to scanline)
- laser driver frequency: 2.6 MHz
- maximum scan line length: 24 mm
- typical scan line length: 8 mm
- optical power: 500 mW
- facets: prism has 4 facets
If users desire an FPGA, they can extend the Beaglebone with for example the Beaglewire.
- Beaglebone green
- Firestarter cape (laser driver, 3x TMC2130 stepper drivers, PWM spindle and fan control)
An image can be uploaded to the scanner and exposed on a substrate.
An exposure result on cyanotype paper is shown below.
Resolution looks to be around 100 microns. Stitching still needs to be fixed, results in white lanes.
The idea is that throughholes are made with a spindle. There is a project on Hackaday where a PCB is cut with an EDM. There is quite a lot of documentation and code available but it does contain mistakes and can be hard to interpret as it is in development. The project has limited peer review. Readers are invited to step forward if they have objections or questions with the claims made.
An exposure goes as follows (for the result see above).
Hexastorm fork of LDGraphy
Hexastorm fork of BeagleG
old FPGA code
Cartesian frame was donated by FELIXprinters.
White paper @ Reprap