How does dual- and tri-layer acrylic work?

Layered acrylic is a solid top color bonded over one color (dual-layer) or two colors (tri-layer) beneath it. Engraving cuts through the top to reveal a lower color, so one sheet produces two or three colors with no ink. The top layer is the bare, unengraved surface — negative space. By default every piece of your artwork engraves to the FIRST engrave layer (the second color), so a normal black cutout arrives ready to engrave with nothing sent to the surface. On a tri-layer you can then send individual pieces DEEPER to the third color for a second, deeper engrave: select a piece (Ungroup a grouped SVG first) and use the Top / Mid / Deep swatches in the selection toolbar or the Layers panel — Top returns a piece to the bare surface, Mid is the first engrave layer, Deep is the bottom layer. Layer order is top → mid → deep; if a sheet you own is stacked differently, contact support and we will correct that material.