Longer Ray5 20W — Machine Reference & Connection Guide
Longer Ray5 20W — Machine Reference
The Ray5 20W is a diode laser engraver/cutter running a GRBL controller. It connects over USB or WiFi and is controlled by LightBurn (recommended), LaserGRBL (free), or the MKSLaser mobile app.
Connection
| Setting | Value |
|---|---|
| Protocol | GRBL 1.1 |
| Interface | USB-A to PC · SD card (offline) · WiFi (MKSLaser App) |
| Baud rate | 115200 |
| Offline mode | Save .gc/.nc to SD card → run from 3.5" touchscreen |
| COM port (Windows) | Check Device Manager → Ports |
| Port (macOS) | /dev/tty.usbserial-XXXX |
LightBurn Setup
- Devices → Add → GRBL
- Select your COM port
- Set baud rate to 115200
- Set work area to 400×400mm
- Origin: Front-left
LaserGRBL Setup (free alternative)
- Connect → select COM port → 115200
- GRBL 1.1 mode
- Home the machine before sending jobs
WiFi / MKSLaser App
- On the 3.5" touchscreen → tap the tool icon → WiFi
- Connect to your network
- Open MKSLaser app (Android/iOS) on the same WiFi
- App discovers the machine automatically — control and monitor remotely
Software
- LightBurn (paid, recommended) — best software for diode lasers, handles vectors and raster engraving, supports camera overlay for positioning
- LaserGRBL (free) — simpler UI, good for getting started
- MKSLaser App — mobile app for WiFi control and remote monitoring
Firmware
Download the Ray5 20W specific firmware from Longer — there are two variants depending on your mainboard:
- With air pump port — use the 24V firmware
- Without air pump port — use the 12V firmware
Update process:
- Download the correct
.binfile from longer3d.com/pages/download-ray5-20w - Copy to SD card root directory (no subfolders)
- Insert SD card while machine is OFF
- Power on — firmware flashes automatically (LED blinks during update)
- Remove SD card after update complete
Air Assist
The Ray5 20W has a built-in air assist port. Connect a small aquarium pump or dedicated laser air assist:
- 3mm ID tubing fits the nozzle
- Run at low pressure (2–5 PSI) for engraving, higher (5–10 PSI) for cutting
- Air assist is mandatory for cutting — without it, char buildup ruins the cut edge
Useful Links
- Ray5 20W firmware & downloads
- Ray5 20W full manual (ManualsLib)
- LightBurn software
- LightBurn docs
- LaserGRBL (free)
- Reddit r/lasercutting
- Longer Facebook group
Common Issues
Machine not connecting: Try a different USB cable (data cable, not charge-only). Some cables only carry power.
Laser firing at wrong power: Check $30 and $31 GRBL settings match LightBurn S-value max (should both be 1000).
Inconsistent engraving depth: Check focal height — run the focus test grid to dial in exact focal distance for your material.
Cuts not going through: Slow down, increase passes. Two passes at 80% beats one at 100% for clean cuts.
Wrong firmware flashed: If the board is non-responsive after flashing, verify which mainboard variant you have (air pump port = 24V, no port = 12V) and reflash the correct file.