DESIGNEROOH - FREE LASER KERF TEST
Free Laser Kerf Test File
Download a free 120×80 mm laser kerf test SVG and use it to measure kerf, test slots and tabs, and find practical settings for your laser cutter and material.
File size: 120 × 80 mm · SVG · Designed for laser cutting tests
What Is Laser Kerf?
Laser kerf is the amount of material removed by the laser beam while cutting. Because the beam has a real width, the final size of a cut part can differ slightly from the original design.
Measuring kerf helps you create better-fitting laser-cut parts, especially when making boxes, joints, slots, tabs, press-fit projects, and other assemblies.
What Is Included?
The Designerooh Free Laser Kerf Test contains five useful test areas inside one compact 120 × 80 mm SVG.
| Test | Purpose | Sizes |
|---|---|---|
| 1. Reference Square | Measure the final size of a known 20 mm square. | 20 × 20 mm |
| 2. Five-Square Test | Measure five touching pieces to estimate average kerf. | 5 × 10 mm squares |
| 3. Frame + Hole | Compare the measured hole size with its nominal size. | 20 mm frame / 10 mm hole |
| 4. Slot Test | Test different slot widths for real-world fit. | 2.6–3.0 mm |
| 5. Tab Test | Test different tab widths for press-fit projects. | 2.8–3.2 mm |
How to Use the Free Kerf Test
Step 1 — Download
Download the SVG file using the button at the top or bottom of this page.
Step 2 — Open in Your Software
Import the SVG into LightBurn or your preferred laser software. Make sure the design is not accidentally scaled.
Step 3 — Use Your Real Material
Run the test using the same material and thickness you intend to use for your project.
Step 4 — Measure
Use a reliable digital caliper whenever possible. Record the measured dimensions of the test pieces and holes.
How to Calculate Kerf
Section 1 — 20 mm Square
Measure the finished width of the 20 mm square.
Example: if the finished piece measures 19.80 mm:
Section 2 — Five 10 mm Squares
Measure the total width of all five pieces after cutting.
This works because the five pieces represent five kerf widths across the complete 50 mm nominal span.
Section 3 — 10 mm Hole
Measure the actual diameter or width of the 10 mm hole.
Example: if the hole measures 10.20 mm:
Kerf = (measured hole − measured plug) ÷ 2
Slot & Tab Fit
The included slot and tab tests help you see how different nominal dimensions behave on your actual machine and material.
Slot Test
The SVG includes slots from 2.6 mm to 3.0 mm. Measure the actual result after cutting.
As a simple approximation:
Tab Test
The SVG includes tabs from 2.8 mm to 3.2 mm. Compare the different sizes against your material and slots.
As a simple approximation:
Using the File in LightBurn
Import the SVG into LightBurn and verify that the dimensions remain correct before running the test.
Black
Black geometry is intended to represent the cutting geometry.
Blue
Blue geometry is used for labels and path-based reference text.
Gray
The gray 120 × 80 mm border is a reference boundary and should not be cut.
Download the Free Laser Kerf Test
Get the 120 × 80 mm Designerooh SVG and test your machine before starting your next laser-cut project.
Important Testing Notes
Use the Same Material
Kerf can change between plywood, MDF, acrylic, cardboard and other materials. Different thicknesses can also produce different results.
Keep Your Settings Consistent
If you want a useful reference value, record the machine, material, thickness, lens and cutting settings used for the test.
Do Not Scale the SVG
The test is designed at 120 × 80 mm. Verify the imported dimensions before cutting.
Repeat Important Tests
If your material or cutting settings change significantly, run a new test instead of relying on an old measurement.
Frequently Asked Questions
What is laser kerf?
Laser kerf is the amount of material removed by the laser beam during cutting.
Why should I measure kerf?
Measuring kerf can help improve the fit and dimensional accuracy of laser-cut parts and joints.
What material should I use?
Use the exact material and thickness you plan to use for your project.
Can I use this with LightBurn?
Yes. The file is an SVG and can be imported into LightBurn. Always verify dimensions and layer settings before cutting.
Is one kerf value good for every material?
No. Kerf can vary with material, thickness, machine, lens, focus, air assist and cutting settings.
What size is the test file?
The SVG is designed at 120 × 80 mm.
Can I use the same kerf value forever?
It is better to re-test when your material, thickness or cutting conditions change significantly.
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Ready to Test Your Laser?
Download the free Designerooh kerf test, run it on your material, record your measurements and use the results to improve your next project.
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