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 Oct 26, 2026, 7:48 PM

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GPath Laser is desktop laser software for macOS and Windows. This guide walks you through connecting a Sculpfun S9 (5 W / 5.5 W diode module) over USB, adding its built-in machine profile, and burning your first engraving — either straight from the app or by saving G-code.

The S9 runs GRBL firmware on a USB serial controller. GPath Laser can control it live — connect, jog, frame, and run — or save G-code for use with other software.

Tested compatibility: The Sculpfun S9 has been tested with GPath Laser over USB using the steps below. Many S9 units ship without limit switches, so the machine can't find its own home position. This guide shows you how to work with that.

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 A data cable — some cables only charge and won't connect.
Computer macOS or Windows 10+. Close any other app that might be using the laser's USB 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 × 400 mm (you can confirm yours with $$ → $130 / $131 in the Console tab)
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 is usually turned off ($22=0)
Reference point / home Bottom left (front-left of the bed)

What's max S? GRBL controls laser power with a number called S. On the S9, S1000 means 100% power, so GPath turns your power % into an S-value for you — 20% becomes S200.

1. Install GPath Laser

  1. Download and install GPath Laser for your platform from gpathsoftware.com.
  2. Open the app. If you have a licence key, enter it in the Licence section of the welcome screen and click Activate. Otherwise, your free trial starts automatically when you're online.
  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. Most S9 units can't home themselves, so you'll set this position manually at the start of each session.
  2. Power on the machine (12 V adapter) and wait a few seconds for the controller to start up.
  3. Connect USB from the S9 to your computer.
  4. Check that your computer can see the laser:
    • macOS: it appears as usbserial… or wchusbserial…
    • Windows: it appears as COM3, COM4, etc. in Device Manager. If no port shows up, install the CH340 USB driver.
  5. Close other laser software — only one app can use the USB port at a time.

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

3. Add the Sculpfun S9 machine profile

A machine profile tells GPath about your laser: its bed size, power range, and the kind of G-code it understands. There are two ways to add one.

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

GPath usually adds the S9 automatically the first time you connect it. If it doesn't:

  1. Open Laser machine setup from either:
    • Laser operations → Laser machine setup… (top menu), or
    • the Machine setup button on the Connect tab of the Laser panel.
  2. Click Detect connected machine.
  3. GPath scans your USB ports and asks the controller what it is.
  4. If the controller identifies itself as a Sculpfun S9, GPath applies the Sculpfun · S9 template automatically. If it shows a generic name like "GRBL 1.1f", that's fine too — you can rename it.
  5. Click Save at the bottom of the setup window.

The Sculpfun · S9 template includes:

  • Controller: GRBL
  • max S: 1000
  • M4 default (dynamic power): on
  • Air Cut (air assist for line operations): on — harmless if you don't have an air assist pump

Option B — Add from a template (if detection doesn't match)

Use this if the S9 isn't detected, or you'd like to set things up before plugging it in.

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

  2. In Search:, type S9, then choose Sculpfun · S9 from the Template: list.

  3. The form fills in the recommended values. Check them before adding:

    Setting Recommended value
    Name: Optional label (e.g. Workshop S9)
    Controller: GRBL
    Post-processor: GRBL 1.1 Laser (recommended)
    Feed display: mm/min
    Work area 410 × 400 mm
    Reference point: Bottom left
    max S: 1000

  4. Click Add machine, then Save.

Make it your default (optional)

In Your machines, click Make default next to the S9 (it gets a ★). New laser projects will then use the S9's work area and reference point automatically.

4. Turn off auto-home (important)

Homing is when the laser moves to its corner until it touches a small switch, so it knows exactly where it is. Many S9 units don't have these limit switches, so homing is turned off in the firmware ($22=0).

If Auto-home when connected is on, GPath tries to home ($H) as soon as you connect, and the S9 replies with error:5 (homing not enabled). To avoid this:

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

You'll set the start position each session instead (section 6).

Does your S9 have limit switches? If homing is turned on ($22=1), you can leave auto-home on and use the home button in the middle of the jog pad on the Move tab. To check, click Settings ($$) on the Console tab and look for $22.

5. Finding your way around the Laser panel

Everything you need to control the S9 lives in the Laser panel, in the right sidebar under Laser operations.

The top of the panel shows the connection status and machine name, e.g. ● Connected · Workshop S9. Below that are five tabs:

Tab What it's for
Move Jog the head, go to an X/Y position, and Set origin here
Origin Choose how the job is placed on the bed (Absolute or Current) — see Work origin
Camera Show a USB camera image on the canvas. The S9 has no built-in camera, so you only need this if you add your own — see Camera calibration.
Console Send commands straight to the controller
Connect Pick your machine, Connect / Disconnect, Re-detect, and open Machine setup

Under the tabs you'll find the main job buttons: Run, Go to origin, Frame, and Fire.

Moving the laser head

On the Move tab:

  • Pick a Move step size (e.g. 1 mm or 10 mm), then click the arrows to jog the head.
  • With your pointer over the jog pad, you can also use the arrow keys — hold Shift to move 10× further.
  • Type an X and Y position under Go to and click Go to move straight there.

Console quick actions

The Console tab has quick buttons for the most useful GRBL commands, so you don't need to remember them:

Button Sends What it does
Status ? Shows the current state and position
Info $I Shows the firmware version
Settings $$ Lists all the controller settings
Unlock $X Clears an alarm so you can move again

Sending is blocked while a job is running.

6. Set up work origin (manual)

The work origin is the point on your material that GPath treats as (0, 0). Without limit switches, you set it at the start of each session.

Before you connect (good habit)

  1. With the power off, gently slide the head to the front-left corner of the frame. You can also jog it there later from the Move tab.
  2. Power on and connect USB.

Absolute origin (best for repeat jobs)

Your canvas's reference corner (Bottom left for the S9) lines up with the point you set on the machine. Whatever you draw near the bottom-left of the canvas burns near that spot on the material.

  1. Jog the head to the front-left corner of your material.
  2. On the Move tab, click Set origin here. This tells the controller "this spot is X0 Y0" (it sends G92 X0 Y0).
  3. Before a run, click Go to origin to send the head back to that spot.
  4. On the Origin tab, make sure Absolute is selected.

Current origin (quick placement)

The job starts wherever the laser head is right now. This is handy for dropping a design onto a specific spot.

  1. On the Origin tab, select Current.
  2. Use the Job origin picker to choose which part of the design sits under the head — for example Center puts the middle of your design under the laser.
  3. Jog the head to the spot you want on the Move tab.
  4. Click Frame to check the placement, then Run.

Unlock after an alarm

If the controller goes into alarm (for example after a reset or a stopped job), the Connect tab shows Machine in alarm — home, or unlock if position is known and an Unlock button. On an S9 without limit switches:

  1. Click Unlock.
  2. Jog back to your corner and Set origin here again before restarting.

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 (see Creating a project).
  2. If the S9 is your default machine, the canvas opens at 410 × 400 mm with a Bottom left reference point. If not, choose the S9 from the machine picker on the Connect tab.

Step 2 — Draw your design

Use the Draw section of the left toolbar. The Drawing docs cover every tool in detail.

Option A — Text

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

Option B — Simple shape

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

Step 3 — Add a laser operation

A laser operation tells GPath how to burn a shape — how much power, how fast, and how many times.

  1. Open the Laser operations tab in the right sidebar.

  2. Under New operation, click Line. A Line follows the outline of your shape, which is great for engraving text outlines or cutting shapes out.

  3. Set up the operation:

    Setting Suggested start Why
    Max Power (%) 15–20 A light mark on scrap — you can always go darker
    Speed (mm/min) 2000 How fast the head moves while burning
    Passes 1 Use more passes to cut deeper
    Dynamic Power (M4) On Lowers power in corners so they don't over-burn
    Air Assist On if you have an air pump Blows away smoke; does nothing without a pump

  4. With the Line panel open, click your text or shape on the canvas to add it to the operation. Selected shapes are highlighted.

  5. Click Save.

For a solid filled area, use Fill instead of Line. To engrave a photo, import a PNG or JPG with File → Import… and GPath creates an Image operation for you.

Shortcut: right-click a shape on the canvas and choose New line operation from selection… or New fill operation from selection….

Step 4 — Preview the job

  1. Check the toolpath lines on the canvas.
  2. Open the Laser Simulator tab to watch the job play out before you burn anything.
  3. Make sure the design fits inside the 410 × 400 mm work area.

Step 5 — Save your project

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

Step 6 — Place material and set origin

  1. Secure your scrap material on the bed.
  2. Jog the head to where the bottom-left of your design should land on the material.
  3. On the Move tab, click Set origin here.
  4. On the Origin tab, check Absolute is selected.

Step 7 — Frame, then run

  1. Click Frame. The head traces the outline of your job so you can see exactly where it will burn. Turn on Low power next to Frame if you'd like a faint visible dot to follow. Adjust the material if needed.
  2. Put on your laser safety glasses, check your ventilation, and click Run.
  3. Watch the first few lines. If something looks wrong, click Stop.

While the job runs you'll see a progress bar with the time left. You can also:

  • Pause and Resume — the laser switches off while paused.
  • Nudge Speed and Power up or down by 10% without stopping the job.

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

Checking focus? The Fire button turns the laser on at very low power (1% by default) so you can see the dot. It switches itself off after 10 seconds.

8. Power and speed settings

Every material behaves differently, so for a new material it's worth running a material test grid. You'll find it under Laser operations → Material test grid… in the top menu.

It burns a grid of squares, each with a slightly different power and speed, so you can pick the one that looks best.

gpath laser material test

Set the number of rows and columns and the power and speed ranges, and GPath builds the grid for you.

Note: GPath creates a laser operation for each square automatically. Deleting the grid from the canvas removes these operations too.

Use the Transform tool to move or resize the grid.

9. Save G-code (optional)

G-code is the list of instructions the laser follows. GPath can send it to the S9 directly over USB, but you can also save it as a file to run in other software.

  1. Open the Laser operations tab in the right sidebar.
  2. In the Setup & output row, click the Save laser operations icon.
  3. Tick the operations you want to include (or click Select All).
  4. Check the Post-Processor is GRBL 1.1 Laser.
  5. Click Save and choose where to save the file.

The base S9 doesn't have an SD card slot, so most people run jobs over USB straight from GPath Laser.

Troubleshooting

Homing failed: error:5

  • Your controller has homing turned off ($22=0) — this is normal on S9 units without limit switches.
  • Turn Auto-home when connected off in Laser machine setup and click Save.
  • Don't send $H or use the home button unless you've fitted limit switches and set $22=1.

Port not listed or connect fails

  • Unplug and replug the USB cable, or try a different cable or port.
  • Quit any other laser software or serial terminal that might be using the port.
  • On Windows, install the CH340 USB driver if Device Manager shows an unknown device.
  • Click Re-detect on the Connect tab after replugging.

"Unrecognized controller"

  • Make sure the machine has finished starting up before you connect.
  • Add the machine by hand from the Sculpfun · S9 template (section 3, Option B).

Alarm / lock state

  • Click Unlock on the Connect tab (or Unlock on the Console tab).
  • Jog back to your front-left corner and click Set origin here again before restarting.

Wrong scale or position

  • Check the work area is 410 × 400 mm in Laser machine setup.
  • Re-check your origin: jog to the right corner and click Set origin here.
  • Always Frame before Run.

Power seems too weak or too strong

  • Check the focus. The S9 is fixed-focus, so you move the whole module up or down to focus it — use the spacer that came with your S9 to set the height.
  • Adjust the operation's Max Power (%) — start low on scrap.

FAQ

Does GPath Laser work with Sculpfun S9?

Yes. GPath includes a Sculpfun · S9 machine template and supports USB connect, jog, frame, run, and G-code export for the S9's GRBL controller.

My S9 has no limit switches — is that normal?

Yes. Many S9 machines ship without them. Slide the head to the front-left corner by hand, turn off auto-home in GPath, and click Set origin here at the start of each session.

What G-code post-processor should I use?

GRBL 1.1 Laser — it's picked automatically for the Sculpfun S9 template. It uses M4 dynamic power, M8/M9 for air assist, and standard GRBL laser commands.

How do I engrave a photo on the S9?

Import a PNG or JPG with File → Import… and GPath creates an Image operation. Adjust the power, speed, and image settings, then frame and run.

Is the S9 5 W or 5.5 W?

Sculpfun rates the diode module at ~5.5 W optical output, and it's commonly called a 5 W class engraver. In GPath you set power as a percentage of max S (1000), so 10% = S100.

Further reading