Carving maps on a CNC router

Difficulty: Intermediate (CAM setup). Time: 2–4 hours including toolpathing and a finishing pass. Best subjects: topography, lake and ocean depth, coastlines, and bold city outlines.

A CNC router and a laser want the same thing from this tool: clean vector layers with a clear depth order. Where a laser cuts each layer from a separate sheet and you glue the stack, a CNC carves the whole relief out of one solid board - each map layer becomes a pocket at a different depth, so the terrain steps down into the wood instead of building up off it.

The presets that shine on a laser as layered stacks are exactly the ones that shine on a router as carved relief: topography, lake and ocean depth charts, and land-and-sea basins. The per-layer SVG export gives you one closed outline per elevation or depth band, which is precisely what your CAM software needs to generate a pocketing toolpath at each step.

Open a relief preset to carve

What You'll Need

A CNC router (Shapeoko, Onefinity, X-Carve, or larger) and CAM software (Carbide Create, VCarve, Fusion 360, or similar)
A solid hardwood blank thick enough for your deepest pocket - basswood, maple, walnut, or a glued-up panel; MDF for a paint-grade carve
A downcut or compression end mill for clean pocket walls (3.175 mm / 1/8 inch is a good all-rounder) and a small V-bit for engraved coastlines and lettering
Optional: tinted acrylic for an inlay water layer, wood glue, finishing oil or paint

Step 1 - Start from a relief preset

Open a preset whose layers already represent depth steps. The best CNC candidates:

Topography - up to sixteen elevation bands, each a closed contour you can pocket at a stepped depth.
Lake Depth Chart and Coastal Depth Chart - bathymetric bands that carve into the board as a basin.
Land and Sea Relief Map - mountains and lake depth in one piece, ideal for a single carved block.
Country Borders Map or a bold City Map outline for a simpler two-level carve.

Fewer, well-chosen layers carve better than all sixteen: 8-10 elevation steps give a clean terrace without an unreasonable number of toolpaths. Delete empty bands (elevations above your peak) before exporting.

Step 2 - Plan your depth-per-step

On a CNC the layers do not stack up, they cut down. Decide your total relief depth and divide it by the number of layers:

Example: a 20 mm-deep carve across 10 elevation bands means each band sits 2 mm lower than the one above it.
The topmost map layer (highest elevation, or the shore plate on a depth chart) is the surface of the board - it is not pocketed. Every layer below it is a pocket cut to its step depth.
Keep the deepest pocket comfortably above your blank's thickness so you do not cut through into the spoilboard.
Steep terrain produces thin slivers between contours; on a router those become fragile walls. Widen your steps or simplify layers if the walls get thinner than your end mill diameter.

Step 3 - Export the layer SVGs

Export the per-layer SVG ZIP - you get one closed outline per band, named in order, which is exactly one pocket region per file.
Turn on small-polygon cleanup to drop tiny outlier islands that would become un-machinable nubs.
Keep the inversion / holes setting as the preset ships it so each depth band exports as a plate-with-hole (the region to leave standing), not a solid blob.
Note the layer order from the on-screen panel - you will assign deepest-to-shallowest pocket depths to match it in CAM.

Choose Your Build Method

From SVG layers to carved relief

Import all the layer SVGs into one CAM file at the same origin so they stay in register. Most software lets you import an SVG straight onto the canvas.
Assign each layer a pocket toolpath at its step depth: the highest band shallowest (or zero), the deepest band at full depth. A roughing pass with your end mill plus a finishing pass cleans the floors.
Use a downcut or compression bit to keep the top edges of each terrace crisp and tear-out free.
Add a V-carve pass for engraved coastlines, the lake name, or coordinates using the text and outline layers - the V-bit gives crisp lettering a flat end mill cannot.
Cut a profile pass last to release the panel from the blank, leaving small tabs so it does not shift on the final cut.
Sand the terraces lightly, then finish with oil for hardwood or paint the pockets for a hypsometric tint (greens low, tans mid, white on the peaks).

Feeds and speeds: treat this like any pocketing job for your material. Hardwoods and acrylic want a downcut bit, conservative depth-of-cut per pass, and chip clearance between passes; MDF carves fast but eats bits, so paint it to hide the fuzz. Always run a test carve of two or three bands on scrap to confirm your depth math before committing a good hardwood blank.

Water as an acrylic inlay

For depth charts, pocket the lake or ocean basin a few millimeters deep across its full outline.
Cut a matching shape from tinted blue acrylic (laser or CNC) and inlay it into the pocket for a glassy water surface.
Alternatively, flood the carved basin with tinted epoxy for a poured-water finish - mask the rim first.

Make It Yours

Carve a favorite mountain (Banff, the Tetons, your local ski hill) as a single hardwood relief block and oil it for a warm, tactile piece.
Paint each pocket a hypsometric tint before a light surface sanding so only the terrace tops stay bare wood.
V-carve the summit elevation and coordinates into the top face.
Glue up a walnut-and-maple striped blank so the carved terraces reveal contrasting wood bands as they step down.
Pour tinted epoxy into a carved lake basin for a bar-top-style water feature.
Mirror the file and carve a two-sided piece: terrain on the front, an engraved coastline map on the back.

Open a relief preset to carve

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