Online CNC guide: design, V-carving, 3D carving and PCB
Router Studio is free CNC software that designs shapes and text, V-carves and makes inlays, carves 3D models and photos, cuts DXF/SVG drawings, mills PCBs from Gerber files, simulates the job in 3D and streams it to your GRBL machine from the browser. No install; your files never leave your computer.
The interface at a glance
- Top menus. File: new project, open, save, add file, Gerber folder. View: layer panel, rulers, grid, rapid moves, zoom. Help: guide, assistant and version information (About).
- Left toolbar. Shapes, text, freehand drawing, nesting, apps and file import.
- Canvas. Millimetre rulers along the top and left edges. Drag a design to move it; right-click to duplicate, align or delete. Switch between Design, Preview and 3D.
- Right panel. The strip at the top holds material, work zero and bit settings. The selected design has two tabs: Cut (cut type, bit, depth) and Shape and position (size, angle, text, position).
- Machine tab. Three steps: 1 Connect, 2 Set the zero point, 3 Carve.
Supported files
| File | Used for |
|---|---|
| Built-in shapes and text | Rectangle, circle, polygon, star, heart, line; text in 6 fonts |
| DXF, SVG | On line, outside, inside, pocket and V-carve |
| STL, OBJ, 3MF | 3D carving: roughing and ball-nose finishing |
| PNG, JPG, WEBP, BMP | Relief from a photo or logo (light = high) |
Gerber (.gtl .gbl .gko .gm1 .gbr) | Copper isolation milling, board outline |
Excellon (.drl .xln) | Drilling; larger holes are milled around |
Folder or .zip | KiCad / EasyEDA Gerber output in one go |
Cut types
| Cut type | What it does | Bit |
|---|---|---|
| On line | The bit centre follows the line; for engraving and line art such as mazes. | V-bit or small end mill |
| Outside | Cuts a part out around its edge, keeping its size. Tabs hold it in place. | End mill |
| Inside | Cuts a hole from the inside, keeping the hole size. | End mill |
| Clears the inside of a shape to a flat floor. Offset or raster fill, optional floor texture. | End mill, ball nose for texture | |
| V-carve | Depth follows the width, giving sharp corners in lettering. Wide areas get a flat floor. | V-bit (+ optional end mill) |
| 3D carving | Carves a model surface with roughing and finishing passes. | End mill + ball nose |
| Isolation, drill, outline | PCBs from Gerber/Excellon files. | V-bit, drill, 1 mm end mill |
Designing shapes and text
- Add. Pick a shape or text in the left toolbar. The new design lands in free space on the stock and the Shape and position tab opens.
- Size it. Enter width, height and angle; "Keep proportions" scales evenly. Set the corner radius, number of corners, font and letter height.
- Edit. "Advanced vector editing" offers offset copies, simplify, point editing and union, subtract or intersect with a second shape. The freehand tool draws by hand.
- Arrange. Use the align buttons, "Center on material", the right-click menu and Nest in the toolbar. Ctrl+Z / Ctrl+Y undo and redo.
Overlapping parts of letters are merged into one outline, so every cut follows only the visible edge. If the bit does not fit a thin part of a letter, the app tells you how much of the area will stay uncut.
V-carving and inlays: step by step
- Select the shape and set the cut type to V-carve in the Cut tab. A suitable V-bit is assigned.
- Enter the depth. This is the maximum depth; wider areas get a flat floor. Pick a "Flat-floor bit" to clear them quickly.
- For an inlay press "Add V-inlay plug". A mirrored plug is created; the "Start depth" leaves a glue gap between plug and pocket.
- Cut separately. Cut the pocket in one board and the plug in a second board of another colour; hide the one you are not cutting. Glue the plug in and sand flush. Try it on scrap first.
3D carving: step by step
- Add the model. Use File → Add file to choose an STL, OBJ, 3MF or a photo. The model shows in 3D; orbit it with the mouse.
- Set size and orientation. Choose the width, depth and the face that points up. Tick "Invert" for a mould.
- Choose the bits. An end mill (e.g. 3.175 mm) for roughing and a ball nose for finishing. Set the raster to "X + Y" for a smoother surface.
- Simulate and carve. Check the carved surface in 3D. Optionally cut the part free along its outline.
PCB from Gerber: step by step
- Open the folder. Use File → Open Gerber folder. Copper, outline and drill layers are recognised; mask and silkscreen are skipped.
- Enter the material. In the Material item of the strip, type the size of the copper board and place the PCB on it.
- Choose the bits. A V-bit for isolation (e.g. 30° · 0.2 mm), a 0.8 mm end mill for holes and a 1 mm end mill for the outline. The app works out the V-bit groove width from the depth.
- Simulate and carve. Jobs run by bit: isolation, drilling, outline. After each job the machine parks and guides you through the bit change.
Nesting, fill and apps
- Nest. Arranges every part on the stock, largest first; parts that do not fit are left to the right of the stock.
- Fill the stock with this. From the right-click menu, fills the stock with copies of the selected part around the other parts.
- Apps. Box maker (5 finger-jointed panels), gear, maze, honeycomb, hole grid, radial array and dog-bone corners. Dog-bones add bit-radius reliefs to inner corners so joints fit fully.
Carving: three steps at the machine
- Connect. Press Connect in the Machine tab and pick your GRBL board's port. Set the work area and the park position in the machine profile.
- Set the zero point. Jog the bit to the start point, set the XY zero, then the Z zero with the paper method. "Trace frame" checks the position without cutting.
- Carve. Start the jobs in order; a checklist opens first. While cutting, change feed and spindle speed in 10% steps. If a bit breaks or the job stops, use "Resume from line".
For stock longer than your machine, turn on tiling in the Work zero panel: the job is split into bands along Y and you move the stock by the given length after each band.
Connecting a machine
Router Studio works with machines running GRBL 1.1: Arduino Uno + CNC Shield V3, 3018-style desktop routers and similar. It connects through the browser's Web Serial API, so use Chrome or Edge. You can also download the G-code as an .nc file and send it with Candle or UGS.
Frequently asked questions
How do I carve text or a logo?
Add Text from the left toolbar or open your SVG/DXF logo. Use V-carve for sharp corners, Pocket for flat-bottomed lettering or Outside to cut the letters out as parts.
Can I use it without a Z probe?
Yes. Lower the bit onto a sheet of paper and press "Set Z zero here". With a probe you can also use automatic Z probing and a height map (auto-level).
Can I open DWG files?
DWG is a closed format. Save the drawing as DXF in AutoCAD, LibreCAD or ODA File Converter and import that.
Are my files uploaded to a server?
No. Everything runs in your browser; your files never leave your computer.
How is it different from Easel?
Router Studio is free with no carve limit, and V-carving, V-inlays, 3D carving, textured pockets, nesting and tiling are open to everyone. It also reads Gerber and Excellon files directly, mills PCB isolation paths and offers height maps (auto-level).