hardware

Casing

The laser-cut-case.ps PostScript file is a somewhat parametrized source for making an acrylic case for LDGraphy.

Use black or dark-red acrylic for all parts except the sled to prevent the 405nm laser to escape in eye-damaging levels. The sled should be cut from fluorescing material.

Do not use glass-clear transparent acrylic for the real machine, a 500mW laser can blind you!

How to cut

The file covers several parts, and depending on which you can fit on your acrylic sheet and/or which you have to re-do, you can choose the ones to be output in the first section that defines the /print-... boolean variables.

The Makefile can create a dxf file that is then usable in any laser cutter, just call make.

There are several colored output layers that have different meaning for your set-up in the laser cutter:

• the 'green layer'. Set to scan engraving.
• the 'blue layer'. Set to vector engraving.

Do the engravings first. Then:

• the 'black layer'. Cut with outward kerf correction (laser cuts outside).
• the 'red layer'. Cut with inside kerf correction (laser cuts inside).
• the 'yellow layer': Set to straight cut, no kerf correction.

Don't cut

• the 'gray layer' (if /print-measures true). Don't cut. Just FYI with measurements and help-lines.

Customization

If you have a different size PCB that you want to expose, you can customize the values in the PostScript file an generate a new DXF that should fit your use-case. Be aware that wider boards means wider exposure angle which in turn means more variation in focus distance (i.e. on average less sharp image).

Start with modifying /pcb-w-mm and /pcb-h-mm, watch the PostScript file in a viewer (e.g. okular). It helps to switch on /print-measures while doing these modifications for more information. Now, modify the /scan-angle so that the polygon mirror fits on the top panel. You might also need to change /scan-redirect-mirror-distance to have the redirect mirror or its reflected beam not conflict with any object.

Note

Nearing final state, ready to be used. This is fully parametrized, but PostScript is not the very best 2D CAD software and updating things is not so easy. I'd be happy if someone could translate that into e.g. Solvespace CAD. Pull requests welcome :)

Cut pattern