Send a drawing to a laser

The Laser panel turns the layers of a drawing into a program for a laser that runs GRBL (most hobby and small-shop diode and CO2 controllers). Type LASER (or LASERCUT) and press ReturnEnter, or choose Laser… in the More menu of the View group. In the ribbon styles it is in the File menu and beside Plot. The panel opens over the drawing and stays open while you draw: the preview follows every change.

What is sent

The panel reads the model (not the sheets), on layers that are on and thawed:

• Lines, arcs, circles, polylines (arc segments stay arcs), ellipses and splines. A shape that ends where it starts counts as closed.
• Blocks are taken apart: an object on layer 0 inside a block goes with the layer of the block reference.
• A hatch sends its boundary, so a hatched logo on a Fill layer is filled.
• A picture (IMAGEATTACH) is engraved on a layer set to Engrave picture, when it lies square (not turned or slanted) and its file is open in CadCraft.
• Text, dimensions, leaders, points and construction lines are not sent; the panel says how many it left out. To burn text, draw the letters as shapes or hatch them.

Sizes go out in millimetres from the drawing's units (UNITS): a drawing in inches is multiplied by 25.4. A drawing with no units set is sent one unit to one millimetre. Tick Only the selected objects to send part of the drawing.

Choose what each layer does

Every layer with something on it is a row. Does sets it to Cut, Score, Engrave lines, Fill shapes, Engrave picture or Not sent, with a Power %, a Speed mm/min and a number of Passes. Each change is one undo step and is saved in the drawing: DWG (every version CadCraft saves) and DXF keep the settings, so the drawing opens with them next time. Other programs open the file as before; they see one unused block named CADCRAFT_LASER (purging it there removes the settings).

• Fill burns the inside of closed shapes in lines, Line spacing apart, at an Angle, both directions or one, with an overscan so the head is at speed when the laser comes on; cross-hatch adds a second pass at 90°. A shape with a hole stays open at the hole.
• Engrave picture turns a picture into dots (Floyd–Steinberg, Atkinson, ordered, or plain black and white at a threshold) or, with Grey levels, into variable power.
• Order: pictures and fills first, then line engraving, then scores, then cuts, so a cut-out part does not move while it is engraved. Within one layer the paths run inside-first (a hole before the plate it is in), nearest next.

Preview, then save

The preview draws what the head does: burning lines in colour, fast moves in grey, and a green box round everything that burns. Below it are the size, the length of burn and a time estimate (without acceleration; a real machine takes longer). Save G-code… writes GRBL laser-mode G-code: $32=1, M4 (or M3) with S values, G0 and G1 moves, M5 at the end. X0 Y0 is the job's lower left corner unless you choose the drawing's origin: set your machine's work zero there.

Send from the browser

In Chrome and Edge, Connect… asks you to choose the laser's USB port. Nothing connects or sends until you press a button. Press Frame the job first: the head traces the box of the job with the laser off (or at the low power you set for a pointer) so you can see where it will burn. Only then does Send job come on, and it goes off again if you change anything. Pause holds the head, Stop holds it, resets the controller (the laser goes off) and sends M5. Where Web Serial is missing (Firefox, Safari, and CadCraft Studio, which has no Web Serial yet) the panel offers saving only: save the G-code and send it with your laser's own program.

Not built yet

Not built yet: other controllers' formats (Ruida, Marlin lasers, vendor files), tabs and lead-ins, kerf offset, material libraries, rotary and Z axes, camera alignment, text as outlines.