Setup guide
Wrong-size marks are usually not a settings problem. They are a setup problem wearing a settings costume.
Before you chase power, frequency, or pulse width, prove that LightBurn knows your galvo, your lens, your field, your red dot, and your focus height.
First file
Config import
Start from the EZCAD or SeaCAD setup files when your seller provides them.
Lens truth
1 lens = 1 profile
A 110 mm lens and a 200 mm lens should not share one guessed device profile.
Proof mark
50 mm square
A measured square reveals scale, skew, mirror, and corner problems quickly.
Last step
Rotary
Cylinder correction is not where you start. It is where you go after flat work is right.
Diagnostic matrix
| Signal | Likely diagnosis | Proof | Next move |
|---|---|---|---|
| The mark is the wrong physical size | Field size, lens profile, focus distance, or imported correction is wrong. | A 50 mm square measures 48 mm or 53 mm even though the design file is correct. | Verify the installed lens, reload the correct COR file, and recalibrate scale before tuning power. |
| The design is mirrored or rotated | Axis direction or galvo orientation was imported incorrectly. | Text reads backward or the preview direction does not match the burn direction. | Fix axis direction in device setup and rerun the text test on scrap. |
| Corners bow or stretch near the edge | Lens correction is missing, wrong, or too optimistic for the field edge. | Center marks look right, but the same square distorts near a corner. | Load the correct COR file or run galvo lens calibration for that lens. |
| Red framing looks right, burn lands elsewhere | The red pointer and marking beam are not aligned in software. | The red box outlines the part cleanly, but the mark is offset by a repeatable amount. | Adjust red-dot offsets after burn geometry is correct. |
Order of operations
Galvo setup has a trap: the machine can mark before it is accurate. A first burn does not prove the lens, geometry, red-dot position, or field size is correct.
Treat the first session like calibration, not production. The goal is a boring square that measures right, lands where the preview says it should, and looks the same near the center and the working edge.
That small drive may contain the machine file, lens correction file, screenshots, driver, and settings that make the galvo usable. Back it up before importing or overwriting files.
Bench proof
Store a dated copy of every .cor, .lbdev, .cfg, markcfg, screenshot, and vendor note.
LightBurn's galvo workflow is built around machine-specific settings. If the seller gives EZCAD or SeaCAD configuration files, import them before manually typing random values.
Bench proof
Open Device Settings and confirm field size, galvo settings, timing, and red-dot values came across.
The field size is the physical area your installed lens can cover at focus. A 110 mm lens, 150 mm lens, and 200 mm lens each need their own correction behavior.
Bench proof
Engrave a known-size square near the center and measure it with calipers.
The red dot helps position work, but it is not proof that the invisible 1064 nm beam is focused. Use a low-risk material and find the smallest, loudest, cleanest mark.
Bench proof
Move Z in tiny increments and keep the height where the mark is narrow, bright, and consistent.
If the test square is mirrored, stretched, rotated, bowed, or trapezoidal, settings cannot rescue it. Correct geometry first.
Bench proof
A 50 mm square should measure 50 mm by 50 mm and sit where the preview says it should sit.
A red-dot preview can be offset from the actual marking beam. LightBurn exposes red-dot settings so framing and burning land together.
Bench proof
Frame a small square, mark it, and compare the red outline to the physical mark.
Cylinder correction adds diameter, circumference, and surface-position variables. Do not debug rotary output while flat-field scale is still wrong.
Bench proof
Prove flat work first, then run a simple line wrap test on a scrap cylinder.
Autopsy
If a mark is wrong, classify the error by what it does physically. Wrong size, wrong location, distorted corners, weak focus, and rotary stretch point to different fixes.
Diagnostic matrix
| Signal | Likely diagnosis | Proof | Next move |
|---|---|---|---|
| The mark is the wrong physical size | Field size, lens profile, focus distance, or imported correction is wrong. | A 50 mm square measures 48 mm or 53 mm even though the design file is correct. | Verify the installed lens, reload the correct COR file, and recalibrate scale before tuning power. |
| The design is mirrored or rotated | Axis direction or galvo orientation was imported incorrectly. | Text reads backward or the preview direction does not match the burn direction. | Fix axis direction in device setup and rerun the text test on scrap. |
| Corners bow or stretch near the edge | Lens correction is missing, wrong, or too optimistic for the field edge. | Center marks look right, but the same square distorts near a corner. | Load the correct COR file or run galvo lens calibration for that lens. |
| Red framing looks right, burn lands elsewhere | The red pointer and marking beam are not aligned in software. | The red box outlines the part cleanly, but the mark is offset by a repeatable amount. | Adjust red-dot offsets after burn geometry is correct. |
| A known setting suddenly looks weak | Focus height, lens selection, or material height changed. | The same preset worked yesterday on the same material, but the workpiece height is different. | Refocus from scratch and confirm the active LightBurn device matches the installed lens. |
| Rotary art compresses or spreads | Cylinder correction, diameter, or rotary calibration is wrong. | Flat work is accurate, but a wrap design does not close or is visibly squeezed. | Measure the actual diameter, use LightBurn cylinder correction, and test with a single wrap line. |
Lens discipline
A larger field lens is tempting because it covers bigger work. It also changes spot size, focus distance, edge behavior, and correction needs. If you swap from a 110 mm lens to a 200 mm lens, create or verify a dedicated device profile instead of reusing a center-field preset.
Save lens-specific names in LightBurn. A boring name like 30W MOPA 150mm lens prevents the expensive mistake of firing a job with the wrong correction profile.
Buying logic
No fiber galvo is plug-and-play in the same way a consumer printer is. The best machines reduce the number of undocumented variables: common controllers, better LightBurn support, real owner communities, and clear lens files.
Least-friction MOPA
Use when
You want a common 30W MOPA path with JPT hardware, LightBurn support, and enough owner knowledge to debug setup faster.
Skip when
You need the fastest possible batch throughput or a larger field included out of the box.
Dual-lens power pick
Use when
You want 60W MOPA capability and included lens flexibility, and you are willing to verify each lens profile carefully.
Skip when
You want a simple one-lens learning path and will not use the extra wattage.
Budget LightBurn learner
Use when
You mostly mark small parts, want LightBurn continuity, and do not need stainless color or a 150 mm field.
Skip when
Tumblers, long knives, or color work are likely within the first year.
Enclosed onboarding
Use when
You value camera alignment, enclosure, and a guided desktop workflow more than raw MOPA color control.
Skip when
Your goal is repeatable MOPA color on stainless or the lowest cost per watt.
Evidence
This guide leans on the LightBurn galvo documentation because the failure modes are mostly software, correction, and geometry problems before they become material problems.
Primary source for field size, red-dot settings, COR file import, and per-galvo configuration behavior.
Primary source for the galvo setup sequence, lens correction topics, focusing, and rotary documentation map.
Used to cross-check current LightBurn galvo setup and calibration concepts.
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