When a Gweike MCore cut fails, do not immediately increase power or reduce speed. First confirm the exact material, actual thickness, selected laser source and complete parameter row. Then check focus, nozzle, assist gas or airflow, pressure, material flatness and positioning.

This guide covers cutting problems. For engraving depth, contrast or surface-marking issues, use the Gweike MCore Fiber vs CO₂ Engraving Settings Guide.

Quick MCore Cutting Problem Diagnosis

Use the symptom below to identify the first checks. Each issue can have more than one cause, so avoid treating a single visual symptom as a complete diagnosis.

Before Changing Any Parameters

Many cutting problems are caused by a mismatch between the workpiece and the selected setup rather than by one incorrect speed or power value.

Open the complete Gweike MCore laser settings and parameters index to find the material-specific guide. For the initial setup workflow, use the Gweike MCore First Cut Setup Guide.

MCore Does Not Cut Through

“Incomplete cutting” can describe several different failure patterns. Diagnose where and how the cut fails before changing any values.

Cut Fails Along the Entire Path

When the laser leaves a visible line but does not cut through anywhere, check the setup in this order:

1. Confirm the exact material.
2. Confirm the measured thickness.
3. Confirm cutting mode.
4. Confirm the correct laser source.
5. Open the matching material guide.
6. Load the complete parameter row.
7. Check focus.
8. Check nozzle and height setting.
9. Check assist gas, pressure or airflow.
10. Check material flatness.
11. Confirm speed and power match the same row.
12. Run another scrap test.

Cut Fails Only in Some Areas

When one side cuts through and another side does not, inspect mechanical and material consistency before changing the complete preset.

Flatten or reposition the material and rerun the same test before changing speed or power.

Part Separates Only After Bending

A cut is not fully successful when the part releases only after forceful bending. Small bridges may remain along the path.

Inspect where the bridges appear, whether they occur at corners or only on one side, and whether flatness, focus, gas delivery or nozzle condition changes across the test.

The First Part of the Cut Is Incomplete

If the path becomes stable after the first few millimeters, inspect the starting area, focus, nozzle, gas delivery, material coating, thickness and the complete starting preset.

Fiber Metal Cutting Problems

Heavy Bottom Dross

Heavy dross is molten material that remains attached to the underside of the cut. Check:

• Focus
• Cutting speed
• Gas pressure and delivery
• Nozzle type, size and condition
• Height setting
• Material thickness
• Sheet flatness
• Surface condition

Heavy dross does not automatically mean the power is too low. Incorrect focus, insufficient gas delivery, a damaged nozzle or a mismatched speed can create a similar result.

Large Burrs

Check the nozzle outlet, nozzle contamination, gas stability, pressure at the required measurement point, focus value, material surface, cutting speed and sheet flatness.

Do not copy the focus from a nearby thickness only because the material name is the same.

Poor Pierce Quality

A damaged or unstable start point may affect the rest of the cut. Inspect material thickness, coating, focus, nozzle, gas selection, pressure, starting position and the complete parameter row.

If the pierce becomes unstable after changing assist gas, confirm that the entire gas-specific preset was changed—not only the gas supply.

Inconsistent Sparks or Interrupted Cut

Spark behavior may indicate that the process is unstable, but visual appearance alone is not an exact diagnosis. Check gas supply, pressure stability, nozzle condition, material surface, flatness, focus, speed and whether the path crosses a support.

Poor Corners and Small Holes

Small holes and sharp corners accumulate heat differently from long straight paths. First confirm that the base preset produces a stable straight cut, then evaluate a square, circle, small internal hole and 90-degree corner.

Do not apply an unverified corner-power percentage or a universal small-hole speed.

Edge Discoloration

Edge color can change with material, assist gas, oxidation, heat input and surface finish. Do not assume compressed air always creates an oxide-free edge or oxygen always creates the cleanest edge.

The parameter tables do not provide measurements for oxide thickness, edge roughness, paint adhesion or welding suitability. Test the actual material when downstream processing matters.

Nozzle Contacts the Sheet

Open the matching metal guide:

Assist Gas and Pressure Problems

Air Pressure Is Low at the Cutting Head

The compressor outlet rating is not necessarily the pressure available at the cutting head. Pressure loss may occur through piping, fittings, regulators, filters, dryers, leaks, restricted hoses or insufficient flow.

Do not compensate for an air-delivery problem by changing focus or power.

Oxygen Cutting Is Unstable

Check the oxygen supply specification, purity, regulator stability, actual pressure, connections, correct double nozzle, nozzle size, focus, height setting, material thickness and complete oxygen preset.

Problems After Switching Between Air and O₂

Confirm all applicable values:

• Speed
• Frequency setting
• Focus
• Nozzle type and size
• Height setting
• Pressure
• Power
• Duty cycle

For the complete comparison, read Gweike MCore O₂ vs Air for Carbon Steel Cutting.

Gas Supply Appears Normal but the Cut Still Fails

A normal regulator reading does not confirm that the complete process is correct. Verify pressure at the required location, available gas flow, nozzle installation, focus, height setting, flatness, speed, actual thickness and the matching parameter row.

CO₂ Non-Metal Cutting Problems

Acrylic Melting

Acrylic melting indicates excessive localized heat, but the cause may be speed, focus, airflow, acrylic type, material flatness, protective film or repeated passes.

Review the Gweike MCore Acrylic Cutting Speed Chart.

Acrylic Does Not Cut Through

1. Confirm the material is acrylic.
2. Confirm the actual thickness.
3. Confirm the 80W CO₂ source.
4. Confirm cutting mode.
5. Load the matching acrylic row.
6. Check focus, speed, power and airflow.
7. Inspect material flatness and any protective film or coating.

Do not assume every clear plastic is acrylic. Unknown plastic should not be processed until its composition is confirmed.

Acrylic Edge Is Rough or Frosted

Check acrylic type, material batch, focus, speed, airflow, protective film, heat buildup, repeated passes and surface contamination. The table provides starting references, not identical edge results across every acrylic formulation.

Wood or MDF Charring

Check speed, power, focus, exhaust, airflow, density, resin content, moisture, glue layers, surface coating and repeated passes.

Review the Gweike MCore Wood and MDF Cutting Parameters.

Wood or MDF Does Not Cut Through

Confirm the exact board type, measured thickness, CO₂ source, cutting mode, focus, speed, power, flatness, glue layers, density, moisture, exhaust and airflow.

Do not immediately increase power. Incorrect focus or a dense glue layer may prevent full penetration even when the power value is correct.

Smoke Staining on Wood or MDF

Check exhaust performance, blocked filters, airflow, surface condition, protective masking, speed, repeated paths and whether smoke is trapped under or around the board.

Leather Burning or Strong Odor

Check natural or synthetic composition, tanning method, coating, adhesive backing, thickness, speed, power, focus, exhaust and airflow.

Review the Gweike MCore Leather Cutting Settings.

Fabric Moves, Melts or Frays

Review the Gweike MCore Fabric and Felt Cutting Parameters.

Why the Same Preset Produces Different Results

A saved preset is a verified starting point for a specific material condition. It does not prove that every future sheet or supplier batch will behave identically.

Material Batch Changes

Wood, MDF, acrylic, leather and fabric can vary between supplier batches. Retest when the supplier or batch changes, and record the new result.

Nozzle Wear or Contamination

A nozzle can affect gas delivery because of debris, outlet damage, incorrect type, incorrect size or poor installation. Inspect it before changing the parameter row.

Focus Drift or Height Changes

Focus can be affected by warped material, raised surfaces, thickness variation or a head-position issue. If the same failure occurs across several known materials, inspect the machine setup rather than editing every preset.

Exhaust and Filter Condition

Reduced exhaust can increase smoke staining, heat buildup, odor, residue, flame risk and lens contamination. Check filters and airflow when a previously stable CO₂ process begins producing more smoke or charring.

MCore Parameter Adjustment Order

How to Run a Controlled Troubleshooting Test

Use a repeatable test instead of a full production design.

Change only one column between tests.

When to Stop Testing and Contact Gweike Support

Stop parameter testing and contact technical support when:

• The material or thickness is not covered by a published guide.
• You would need to estimate an unlisted parameter row.
• The nozzle repeatedly contacts the workpiece.
• Gas supply cannot remain stable.
• Pressure at the cutting head is abnormal.
• The same failure occurs on several verified materials.
• Focus or positioning cannot remain consistent.
• The machine reports motion, sensor or software alarms.
• The nozzle, lens or protective optical component may be damaged.
• A complete verified preset cannot produce a stable test.
• Oxygen supply installation or adjustment is required.
• The material produces abnormal smoke or chemical odor.

Material Safety

Do not repeatedly test an unknown material to determine whether the settings can be improved. PVC and chlorine-containing materials may release hazardous and corrosive fumes.

Read why you should not laser cut PVC and safer alternatives.

Stop the job when you observe sustained open flame, abnormal chemical odor, corrosive fumes, unexpected colored smoke, uncontrolled material movement, nozzle contact or unstable gas delivery.

Frequently Asked Questions

MCore Cutting Troubleshooting Checklist

Related Gweike MCore Guides