GPath Laser

Set Up Sculpfun S9 with GPath Laser

Connect a Sculpfun S9 diode laser to GPath Laser on Mac or Windows — USB setup, machine profile, manual origin, first project, and troubleshooting.

Last updated Jul 26, 2026, 11:41 AM

Download GPath Laser

GPath Laser is desktop laser CAM software for macOS and Windows. This guide shows you how to connect a Sculpfun S9 (5 W / 5.5 W diode module) over USB, configure the built-in machine profile, create your first engraving project, and run a job from the app or export G-code.

The S9 runs GRBL firmware on a USB serial controller. GPath Laser supports live control — connect, jog, frame, and run — as well as G-code export for use with other senders.

Tested compatibility: The Sculpfun S9 has been tested with GPath Laser over USB using the workflow below. Many S9 units ship without limit switches, so homing is disabled in firmware — this guide covers that setup explicitly.

Table of contents

What you need

Item Notes
GPath Laser macOS or Windows. Download from gpathsoftware.com.
Sculpfun S9 Open-frame diode laser with a fixed-focus module and sliding Z adjustment.
USB cable Data-capable USB (not charge-only).
Computer macOS or Windows 10+. Close any other app that may hold the serial port.
Laser safety glasses Required — the S9 is an open-frame machine. Use laser-rated eyewear.
Material Plywood, MDF, cardboard, or dark acrylic for your first test engrave.

Sculpfun S9 specifications (for GPath setup)

Spec Value
Engraving area 410 × 415 mm (verify with $$ → $130 / $131 on your controller)
Laser module ~5.5 W optical output (often marketed as 5 W class)
Controller GRBL
Serial speed 115200 baud, 8N1
Max S-value 1000 (GRBL default)
Recommended post-processor GRBL 1.1 Laser
Limit switches Often not installed — homing usually disabled ($22=0)
Reference point / home Bottom-left (front-left of bed) when setting origin manually

1. Install GPath Laser

  1. Download and install GPath Laser for your platform from gpathsoftware.com.
  2. Launch the app and complete licence activation if prompted. Alternatively, a 30-day free trial is activated.
  3. On the welcome screen, click New Laser Project to open the drawing workspace.

2. Preparing the S9

  1. Position the laser head at the front-left corner of the bed (the usual work-zero corner on GRBL diode lasers). On many S9 units there is no automatic homing, so you set this position manually each session.
  2. Power on the machine (12 V adapter) and wait for the controller to finish booting.
  3. Connect USB from the S9 to your computer.
  4. Confirm the machine appears as a USB serial device:
    • macOS: /dev/cu.usbserial…, /dev/cu.wchusbserial…, or similar
    • Windows: COM3, COM4, etc. in Device Manager (install CH340 driver if the port is missing)
  5. Close other laser software that might lock the port.

Safety: The S9 has a protective shroud on the laser module, but the frame is open. Never look at the beam, and wear appropriate laser safety glasses whenever the machine is powered.

3. Add the Sculpfun S9 machine profile

You can add the machine in two ways.

Option A — Detect connected machine (when USB is plugged in)

If machine is not detected when first connected:

  1. Open Laser machine setup from either:
    • Laser operations → Laser machine setup… (top menu), or
    • The Setup button next to the machine selector in the right sidebar.
  2. Click Detect connected machine.
  3. GPath scans USB serial ports and probes the controller.
  4. If the firmware banner contains Sculpfun and S9, GPath applies the Sculpfun · S9 catalog preset automatically.
  5. If detection succeeds but the name is generic, you can rename the profile under Your machines (optional Name field).
  6. Click Save at the bottom of the setup window.

When matched, the preset includes:

  • Controller family: GRBL
  • Max S: 1000
  • Dynamic power: on (M4)
  • Air assist default (vector cuts): on (M8) — harmless if your machine has no air assist hardware

Use this if machine not detected, or you want to set up before connecting.

  1. In Laser machine setup, click Add new machine.

  2. Search or scroll to Sculpfun · S9.

  3. Adjust settings before adding:

    Setting Recommended value
    Name Optional label (e.g. Workshop S9)
    max S 1000
    Feed display mm/min
    Work area W×H 410 × 415 mm
    Reference point Bottom-left

  4. Click Add machine, then Save.

Set as default (optional)

In Laser machine setup, mark the S9 as your default machine for new projects. New laser projects will then use its work area and reference point automatically.

4. Disable auto-home (important)

Many Sculpfun S9 units do not have limit switches. Homing is disabled in GRBL ($22=0). If Auto-home when connected is on, GPath sends $H on USB connect and the controller responds with error:5 (homing not enabled).

  1. Open Laser machine setup.
  2. Turn Auto-home when connected off.
  3. Click Save.

You will set work zero manually each session (section 6) instead.

If your S9 has limit switches and homing enabled ($22=1), you may leave auto-home on and use the Home button on the Move tab. Check with $$ in the Console tab.

5. Finding your way around the right sidebar

In the right sidebar > laser operations > laser, you will find controls for setting up a job.

When connected, the status indicator turns green and shows the controller state. Useful tabs:

Tab Purpose
Connection Connect / disconnect, refresh probe
Position Origin mode
Move Jog pad, go-to XY, set origin
Console Console — send $I, $$, $X, etc.

The S9 has no built-in camera — the Cam tab is only relevant if you add a separate USB camera in GPath settings.

Console quick actions (GRBL)

On the Console tab, use quick buttons for Status (?), Info ($I), Settings ($$), and Unlock ($X after an alarm). Sending is blocked while a job is running.

6. Set up work origin (manual)

Without limit switches, treat every session like a manual alignment job.

Before you connect (good habit)

  1. With power off, slide the head to the front-left corner of the frame. Or, reposition inside the Move tab.
  2. Power on and connect USB.

Machine work zero (0, 0) matches the project reference origin (bottom-left of the canvas if you chose that reference point).

  1. Jog the laser head to where the project origin should be on your stock (usually the front-left corner of the material).
  2. On the Move tab, click Set origin (sends G92 X0 Y0 Z0 — work zero at the current head position).
  3. Use the Go to origin button to return to (0, 0) before a run.

Current origin (spot placement)

The job starts wherever the laser head is when you press Run or Frame.

  1. Select Current on the Position tab.
  2. Use the job origin selector to choose how the design anchors to the head (e.g. center of the job at the current spot).
  3. Jog to the desired position on the Move tab.
  4. Press Frame (outline at power 0) to verify placement, then Run.

Unlock after alarm

If the controller shows an alarm (e.g. after a reset or aborted job), open the Console tab and click Unlock before jogging or running again.

7. Create your first project (step-by-step)

This walkthrough engraves a simple text label on scrap material.

Step 1 — Start a new laser project

  1. From the welcome screen, click New Laser Project.
  2. Select the Sculpfun S9 machine and confirm work area 410 × 415 mm with Bottom-left reference in Laser machine setup.

Step 2 — Draw your design

Use the left toolbar Draw section:

Option A — Text

  1. Click the Text tool.
  2. Click the canvas to set text position.
  3. Enter your text (e.g. Hello S9) in the shape editor on the right.
  4. Set font size. For a first run, place text a few centimetres inset from the bottom-left corner of the canvas.
  5. Click Create.

Option B — Simple shape

  1. Click Square or Circle.
  2. Set dimensions (e.g. a 50 mm square).
  3. Click Create.

Step 3 — Add a laser operation

  1. Open the Toolpaths tab in the right sidebar.

  2. Click the Line button to create a vector engrave/cut operation.

  3. In the operation panel:

    • Operation type: Line
    • Power: start at 15–20% for a light engrave on scrap
    • Cut speed: 2000 mm/min
    • Passes: 1 for engraving
    • Dynamic power: leave on (M4)
    • Air assist: leave on if you use an air assist kit, otherwise it has no effect on most S9 devices

  4. Link the operation to your shape by clicking it on the canvas with the Line panel open.

  5. Save the toolpath.

For a filled area, use Fill instead of Line. For a photo, import a PNG/JPG and the photo engrave operation will automatically generate.

You can also right-click a vector on the canvas to quickly create a Line or Fill operation.

Step 4 — Preview the toolpath

  1. Confirm the toolpath overlay on the canvas.
  2. Open the Laser Simulator tab to step through the job.
  3. Check the design fits inside 410 × 415 mm.

Step 5 — Save your project

  1. File → Save Project (⌘S / Ctrl+S).
  2. Name the file (e.g. my-first-s9.gpath-laser).

Step 6 — Place material and set origin

  1. Secure scrap material on the bed.
  2. Move the head to the front-left corner of the bed.
  3. Jog to where the bottom-left of your design should land on the stock.
  4. On the Move tab, click Set origin.
  5. Set Position tab to Absolute.

Step 7 — Frame, then run

  1. Click Frame — the head traces the job boundary with the laser off to visually see the engrave/cut area. Adjust position if needed.
  2. Put on laser safety glasses, confirm ventilation, and click Run.
  3. Watch the first few lines, press Stop if placement or power looks wrong.

Tip: Always Frame before the first burn on new material. Start with low power and one pass, then increase power or passes for cuts.

8. Power and speed settings

For a new device or material, it is recommended to run a material test grid. You can find this in the top navigation bar > laser operations > material test grid.

This enables a grid of squares with a progressive range of speed and power settings.

gpath laser material test

Set the number of rows and columns, min and max power/speed, and GPath Laser will automatically create a grid using the supplied range.

Note: Laser operations are auto-generated for each speed and power combination. These are also removed if deleting the grid on the canvas.

Use the Transform tool to move or adjust size.

9. Save G-code (optional)

To run the file from another sender or SD workflow:

  1. File → Save G-code…
  2. Confirm the post-processor is GRBL 1.1 Laser.
  3. Select toolpaths and choose a save location.

The stock S9 is primarily used over USB streaming from GPath Laser, there is no built-in SD slot on the base S9 frame.

Troubleshooting

Homing failed: error:5

  • Your controller has homing disabled ($22=0) — normal on S9 units without limit switches.
  • Turn Auto-home when connected off in Laser machine setup and Save.
  • Do not send $H or press Home unless you have installed switches and enabled $22=1.

Port not listed or connect fails

  • Unplug and replug USB, try another cable or port.
  • Quit any other software which may be using the ports, and serial terminals.
  • On Windows, install the CH340 USB-serial driver if Device Manager shows an unknown device.
  • Click Refresh on the Connection tab after replugging.

"Unrecognized controller"

  • Ensure the machine finished booting before connecting.
  • Add the machine manually from the Sculpfun · S9 catalog.

Alarm / lock state

  • Send Unlock ($X) on the Terminal tab after clearing the fault.
  • Jog to your front-left reference and Set origin again before restarting.

Wrong scale or position

  • Confirm work area 410 × 415 mm in machine setup.
  • Re-check origin: jog to the correct corner and Set origin.
  • Use Frame before Run.

Power seems too weak or too strong

  • Check focus: the S9 uses fixed-focus with a sliding module. It may need to be moved up/down (s9 comes with a vertical spacer to position).
  • Adjust operation power % — start low on scrap.

FAQ

Does GPath Laser work with Sculpfun S9?

Yes. GPath includes a Sculpfun · S9 catalog profile and supports USB connect, jog, frame, run, and G-code export for GRBL-based S9 controllers.

My S9 has no limit switches — is that normal?

Yes. Many S9 machines ship without homing switches. Position the head manually at the front-left corner, disable auto-home in GPath, and use Set origin each session.

What G-code post-processor should I use?

GRBL 1.1 Laser — selected automatically for the Sculpfun S9 profile. It outputs M4 dynamic power, M8/M9 air assist commands, and standard GRBL laser G-code.

How do I engrave a photo on the S9?

Import a PNG or JPG via File → Import… to create an Image operation. Adjust power, speed, gamma, and white threshold, then frame and run.

Is the S9 5 W or 5.5 W?

Sculpfun specifies ~5.5 W optical output on the diode module, it is commonly referred to as a 5 W class engraver. GPath power is set as a percentage of max S (1000), e.g. 10% = 100.

Further reading