CD/DVD Data Destruction: Mariner’s Compass Coasters

Snap all the Mariner’s Compass inset layers together into a single LightBurn layout:

Scale it to 120 mm OD, delete the innermost circles under 15 mm diameter, then go wreck yourself some CDs and DVDs:

Those were test pieces to figure out speeds and powers starting from the polycarbonate settings used for the Guilloché DVD now serving as a coaster atop the laser.

When you’re looking to destroy the surface, then pretty doesn’t matter, but they come out surprisingly nice in a techie sort of way:

That’s burned into the clear side of the CD before I figured out how to control the power at the starting points.

This CD-R came out a nice silver, with the tracks burned into the data / label side:

The polycarb tends to scorch & discolor at the starting point of each polygon, where the laser dwells momentarily after lighting up. Avoiding that requires setting the minimum layer power 1% below the Ruida controller’s minimum firing power. In this case, running the layer at 7% minimum with the controller set to fire at 8% completely eliminates the scorches.

The maximum power is about 10% for the clear side. The data side requires only 10% for lightly coated CD-R / CD-RW and maybe 25% for the heavily inked labels of pressed CDs (like the Dell reinstallation CD in the first picture). It helps to start with a vast supply of unwanted discs.

Suiting action to words:

That’s a CD-R wrecked on the data side, stuck to an MDF disk with a cheap craft adhesive sheet and a cork disk wood-glued to the bottom. Carefully hidden here, the central hole sports a 15 mm chipboard disk contrasting horribly with the CD; it cannot be more than 1 mm thick to avoid having it stick up beyond the plastic surface and chipboard is what I have in that thickness.

The advantages of wrecking the data side:

• Leaving the clear side smooth, so crud won’t accumulate / grow in the grooves
• Absolutely, positively, utterly destroying the data track

The advantages of wrecking the clear side:

• Maybe breaking the seal formed by condensation under the mug / glass / cup
• Leaving the data side intact, so the coating won’t disintegrate and peel off the adhesive

In either case, however, I’m sure the data is gone.