I press Engrave and the head drives to the edge of the machine. Why?

Almost always because the machine has no homing cycle (GRBL reports $22=0), so it has never found the corner of its bed — it only knows where it was switched on. Machine Home measures every job from that corner, so the job runs somewhere else entirely. Switch to Custom Origin, jog the head to where the job should start, and press Set Zero.

How do I tell whether my machine can home?

Open the console in Lùmen, type $$ and look for the $22 line. $22=1 means a homing cycle is configured; $22=0 means there are no limit switches to home against, and a homing command would be refused with error:5. Most compact and foldable diode engravers ship with $22=0.

My machine does have limit switches, but the job still lands in the wrong place.

Then home it before you set a zero. GRBL counts steps, not position: a head pushed across the bed by hand does not change the machine position at all, so a zero taken after moving the head by hand is measured from a corner that is no longer where the machine thinks. Home first, jog, then Set Zero.

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My laser moves to the wrong place when I start a job

Machine & jobs · Updated: August 28, 2026

You connect, the arrows move the head fine, you press Engrave — and instead of going to your workpiece the head drives to the far edge of the machine and stops there, sometimes with an error on the machine's own display. Nothing you did was wrong. This is almost always one thing: your machine has no homing cycle, so it has never found the corner of its own bed.

The fix, in two clicks

In Position, choose Custom Origin instead of Machine Home.
Jog the head to the point where you want the job to start — the bottom-left corner of your material is the usual choice.
Press Set Zero, then Engrave.

That's it. Your design is now placed relative to a point you can see, and nothing needs homing. The canvas crosshair is the spot you just set: what you draw above and to the right of it burns above and to the right of it, at the same distances.

Why it happens

A laser controller has no idea where its head is. GRBL counts steps — it knows only how far it has commanded the motors to move since it was switched on. There are no encoders and nothing that senses position.

A homing cycle is how that gets fixed: the machine drives each axis until it trips a limit switch, and from that known corner it can count outward with confidence. Machine Home mode assumes exactly this has happened — it treats your design's position on the canvas as a position on the bed, measured from that corner.

On a machine with no limit switches there is no such corner. The controller's zero is simply wherever the head happened to be when you powered it on. So a design placed 60 mm up the canvas is sent 60 mm up from that arbitrary point — and if the head started mid-bed, that lands past the end of the rails. Machines like this usually also ship with soft limits and hard limits switched off, so nothing in the firmware stops the move either: the head simply runs to the mechanical stop.

How to check your machine in ten seconds

Open the console (the terminal icon in the status strip at the bottom), type $$ and press return. In the list that comes back, find the line beginning $22:

$22=0 — no homing cycle. There are no limit switches to home against, and a homing command would be refused with error:5. Use Custom Origin, as above. Most compact and foldable diode engravers ship this way.
$22=1 — a homing cycle is configured. Machine Home is available to you; read the next section, because there is a second way to land in the wrong place.

Two neighbours are worth a glance while you are there: $20 (soft limits) and $21 (hard limits). If both read 0, the firmware will not stop a move that leaves the bed — which is why an off-bed job on these machines ends against the mechanical stop rather than with a polite alarm.

If your machine can home and it still goes wrong

Then the usual cause is a zero taken without homing first. The same fact as above bites from the other side: because GRBL counts steps, a head you push across the bed by hand does not move the machine's idea of its position by a single millimetre. Set a zero after doing that and it is recorded against a corner that is no longer where the machine believes it to be — and every safety check measured from it inherits the error.

The order that always works: home the machine, then jog to your start point with the arrows, then Set Zero. Jogging is fine — the controller counts those moves. Pushing the head by hand is what breaks the count.

What Lùmen does about it

Lùmen reads $22 from your machine when it connects, and acts on it:

It never asks a machine to home when it can't. The Home command is greyed out, and starting a job skips the homing step instead of waiting forever for an answer that will never come.
It moves you out of Machine Home the moment it learns the machine has no homing cycle, and says so in the console. The mode stays available — if you park the head on the corner by hand before switching on, Machine Home is genuinely correct — but it is no longer the silent default on a machine where it is a guess.
It warns rather than pretends. When the position it is working from is assumed rather than measured, a yellow note says so, and starting a job asks once before it moves.

Still stuck?

Reach out to support with your engraver model, the full $$ output (there's an export button at the top right of the console), and what the machine's own display said — that is normally enough to pin it exactly. If the machine isn't showing up in the device list at all, start with the detection FAQ instead; for power and speed once the position is right, see the laser engraving settings chart.