CNC Laser Engraver

I have set out to design and manufacture my own CNC laser engraver. I plan on doing the mechanical, optical, electrical and thermal design and using open source CNC laser software to run it. As it stands, I am done with the first revision of the Frame CAD and optical design and working on integrating electronics and motion (motors, belts and pulleys).

Laser Engraver Specifications

I have completed the first revision of CAD and am happy to present it to you. The features include/will include:

• 32.5in x 24.3in work bed

• 0mm - 36mm part thickness allowance (i.e. how thick the material you are engraving is allowed to be given the focal length of the lens)

• Motorized CNC X and Y axes.

• Water cooling

• 5W, 447nm laser diode

I intend to 3D-print anything that is not 80-20 aluminum extrusion or laser diode housing. I plan on buying aluminum and brass stock and manufacturing the laser diode housing myself. The collimation optics are likely going to be purchased from Edmund Optics.

Future Improvements

I already have several improvements that I hope to apply to future revisions. As I find time I will add these to the model.

• Overall form will likely change. Based on some market research that has been done since the first design, I have come to find a better design than what I had initially thought of. One benefit to keeping the current design form is that there is potential for this design to be a modular CNC laser engraver/router down the line, but these are desicisions that I will make in the coming months.

• Motor mount assemblies for the X and Y axes. I intend on having these be CNC operated, so the first step in this process is having means of attaching the motor to the frame. This should be a simple addition.

• Bearing blocks for the X and Y axis. The current design uses sliding blocks instead of bearing blocks. These sliding blocks slot into the interior of the 80-20. I can potentially see binding and wear/tear issues with this model so two things need to be done about this:

  • I need to source bearings that are small enough to fit inside of the 80-20 canals. This has been a challenge but I am sure they are out there

  • Once I have those bearings, I need to design bearing blocks and apply them to the design

• The Z-axis is not currently motorized. As it stands it is just a set screw that The module for motorizing it is my first priority for future revisions.

• The work bed is currently quite large and only supported in its central region. I plan on using MDF for the bed of the engraver, which will weigh about 20 lbs. Solutions to this include

  • Using a lighter material for the work bed

and/or

• • Designing a larger structure to support the bed. I expect this to involve multiple pieces and some assembly, but will likely improve the function and rigidity of the design

• I have designed using the thinnest (cheapest) 80-20 aluminum extrusion available. During building/testing, if this proves to not be strong enough, I will have to do some light remodeling in order to bulk up the structure

• I need to look into the specification sheet for the laser diode that I am purchasing to see if it has a Gaussian Beam Profile. If it does, that could affect the layout of the collimation optics

Below you can find the .STEP file for the main assembly and some of the sub-assemblies: