Making a Christmas Light Box with a laser cutter

Making a Christmas Light Box with a laser cutter

This is a project using a 50 watt Chinese laser cutter from E-bay. 

I started with a box of the dimensions I needed using https://makeabox.io/ or http://www.makercase.com/

Then I edited that to create the light box using Inkscape to make the SVG. Finally saving a copy as a DXF file to port it to RDworks (software that came with the laser cutter). In RDworks I set up the engraving and cutting routines and then moved it to the laser cutter.

In future I will be sanding the exterior of the box after assembly to smooth out the tabs. I found that after sanding you get a perfectly smooth finish that's ready for Danish oil or any paint colour of your choice. It's simply glorious to have a 'touch smooth' finish to the exterior.

A word on the laser cutter:
I found that the Chinese laser cutters work well straight out of the box. However, you need to tweak the setup of the mirrors and lens to ensure the beam is accurate no matter where on the cutting board it is. This can be complicated and there are many compromises to be made. You will find the so-called 'sweet spot' where the cutter works perfectly. Then with adjustment you can extend the sweet spot across most of the board.

I found the perfect way to test the focus in various parts of the board. Set the max power to 30% and the speed to your optimal cutting speed (7mm/sec). Then press the pulse button whilst using the arrow key to move the head. It performs a perfect cut. I just drew squares to see gauge the cutting quality across the board. I should say this is for 3mm thick MDF.

NB: I did cut 18mm pine board using the above method by using 4 passes. Going over the same cut 4 times did get me a vertical cut. You may need to adjust the height of the material between passes to get that optimal focal length.

With my cutter, the board itself is not level and to level it means a lot of dis-assembly to rectify it. So I opted to use blocks to raise the material above the board and level it. This also adds to the ventilation beneath the job to vent hot smoke away from the material being cut (reducing staining of the underside). I also leave the laser's lid slightly open leaving a 2cm gap in the front. This creates a 'pathway' for fresh air to enter the device from the front and the fan to blow the smokey air out from the back. You want the smoke drawn down away from the material as quick as possible.

Also make sure the laser head (the lens part) is vertically level. You want cuts that create that perfect vertical line. The height of the lens (gap between the lens and the final mirror) will get you that perfect focal length for cutting.

Also many YouTube channels will give you instructions for masking tape across the apertures for the mirrors to check the mirror angles. Please be careful because the ash from this process may fall into the tube containing your lens. A quick swab with alcohol on a cotton bud will  fix this asap. Just a reminder this should always be the last step after aligning your mirrors as a dusty lens will make all that work futile.

There's lots of adjustment and when you get it right HAPPINESS!