The set-and-forget Genmitsu laser: a 5.5W diode whose focus is fixed at 20 mm, so there is no lens to twist, only one height to set above the work before each burn.
The FL55P's defining feature is what it leaves out. There is no adjustable focus ring; the optics are set so the beam comes to its smallest point 20 mm below the module, and the only setup step is getting the head to that height above the work.
Genmitsu argues that fixed focus gives a smaller spot than adjustable modules at the same power. A tighter spot concentrates the energy, which is why the maker claims a one-pass cut through 3 mm linden, a result it says adjustable modules of the same power do not reach.
The trade-off shows on stock that is not flat. A bowed board or a thick blank with a sloping face moves in and out of the 20 mm focal point, and the burn gets wider and lighter where it drifts.
Genmitsu names the 3018-PRO, the 3020-PRO MAX, the ProverXL 4030 and the Cubiko. On a 3018-PRO the module turns the router into a two-head machine: mill a blank with the 775, swap to the FL55P, and burn detail into the same part. The 3018 laser entry sets it against the other heads for these frames.
| Spec | Value |
|---|---|
| Model | FL55P |
| Maker | Genmitsu |
| Type | Fixed-focus diode laser module kit |
| Optical power | 5.5W |
| Focal distance | 20 mm, fixed |
| Maker's cut claim | 3 mm linden wood in one pass |
| Duty | Full power for 8 hours without light decay (maker rating) |
| Rated life | Up to 10,000 hours |
| Cooling | Large aluminium heatsink with cooling fan |
| Drive | External ACC constant-current mode, feedback control circuit |
| Input voltage | 12V |
| Input current | 2A |
| Size | About 90 × 33 mm (3.54 × 1.3 in) W × H |
| Material | Aluminium |
| Uses | Engraving, cutting, scribing, drilling thin stock |
| Compatible machines | Genmitsu 3018-PRO, 3020-PRO MAX, ProverXL 4030, Cubiko |
Diode lasers lose output as they heat up, and a small head on a long job can fade before the last line is burned. The FL55P answers that with a large aluminium heatsink and a fan, and Genmitsu rates it for eight hours at full power without light decay.
That duty rating suits the jobs where a laser runs longest: photographs on wood, dense fill patterns and batches of identical tags. A 300 × 180 mm bed full of coasters can run for hours at engraving speeds.
| Job | FL55P fit | Tip |
|---|---|---|
| Photo engraving on basswood | Strong; the heatsink holds output steady | Dither the image and test on scrap |
| Batch of leather tags | Good at low power | Vegetable-tanned leather only |
| 3 mm linden cut-outs | Maker rates one pass | Keep the stock flat at 20 mm |
| Card and paper | Clean at low power | Watch for flare-ups |
| Thick plywood | Slow, several passes | Step Z down between passes |
Thicker cuts need the Z axis to help. The focal point sits 20 mm below the module, so after the first pass it lies above the bottom of the kerf; stepping Z down by a millimetre or so between passes moves it back into the cut. Without that step, each extra pass does less than the one before.
Genmitsu puts diode life at up to 10,000 hours. Keeping the window clean and the fan clear of dust helps the diode reach that, since dirt on either one traps heat at the head.
The FL55P runs at 12V and draws 2A, and its drive electronics sit outside the diode housing rather than inside it. On a Genmitsu 3018-PRO, the module plugs into the controller's laser header, which supplies power and the PWM signal that sets brightness.
GRBL controls laser power with the same S value it uses for spindle speed. The only difference on the board side is which output the module connects to, and which mode GRBL is in.
On a Genmitsu 3018-PRO the header and voltage match the module. On other brands, check the header voltage with a meter before plugging in, because a 24V feed will damage a 12V driver.
The software entry walks through LaserGRBL's first-job settings on a 3018.
Genmitsu sells two 5-class heads for the 3018-PRO, and they suit different habits. The FL55P is the older design, with fixed focus and an external drive; the XCFL55-33 is newer, lighter, and carries its driver inside the head.
Neither is simply better. The choice rests on how often the work height changes and how much cutting is on the list. An owner who engraves flat 3 mm and 6 mm sheet all week will rarely miss an adjustable focus; one who burns logos into live-edge slabs, bowed boards and other uneven pieces will reach for the XCFL55-33's focus module often.
| Point | FL55P | XCFL55-33 |
|---|---|---|
| Power | 5.5W | 5W (5000mW) |
| Focus | Fixed at 20 mm | Focus module in the shield |
| Maker cut claim | 3 mm linden, one pass | 8 mm pine, one pass |
| Driver | External, constant current | Built into the head |
| Machines named | 3018-PRO, 3020-PRO MAX, ProverXL 4030, Cubiko | 3018-PRO, PROVer, PROVer V2 and more |
Before ordering, check the machine against Genmitsu's list, confirm the board has a 12V laser header, and plan for eye protection and smoke extraction. A diode laser on a 3018 fills a room with smoke quickly, and the fumes from wood and leather are worth venting outdoors.
Set the module 20 mm above the work surface. There is no lens to turn, so a 20 mm gauge block makes setup quick.
Genmitsu rates it for 3 mm linden in one pass. Thicker wood takes several passes, with Z stepped down a little between them to keep the focus in the cut.
Genmitsu names the 3018-PRO, 3020-PRO MAX, ProverXL 4030 and Cubiko.
12V at 2A. Check that the controller's laser header supplies 12V before connecting it.