5 Most Common Diode Laser Cutting Machine Myths Busted 

Meet the Lasers

1. 5W Sculpfun S6 – The Entry Level

2. 10W Creality Falcon – Mid-Tier Challenger

3. 20W Longer Ray5 – Performance Beast

4. 33W xTool P2 – High-End Powerhouse

The Testing Methodology

1. Power vs Beam Size: What Actually Matters

2. Material Cut Test: Controlled and Repeatable

3. Fastest Speed Cut Test: Measuring Performance

4. Kerf Test: Precision Evaluation

5. Why Focus and Lens Matter in Beam Behavior

Laser Myth #1 – Laser Module Size Doesn’t Affect Power

1. Energy Density vs Output Power Explained
2. The Truth About 10W vs 33W Lasers

Laser Myth #2 – More Diodes = Bigger Beam

1. Lens Design and Focal Length Misconceptions

2. Spot Size Does Not Define Beam Quality

Laser Myth #3 – Larger Beam Means Wider Kerf

1. The Role of Beam Shape on Kerf

2. Why 5W Lasers May Have Larger Kerf Than 33W

Laser Myth #4 – Adding Diodes Causes Power Loss

1. Explaining Beam Combining and Optical Loss

2. Stacked Diodes & Power Efficiency

Laser Myth #5 – Higher Power = Deeper Cuts

1. Optical Focus and Material Depth Cutting
2. The Focal Lens is the Real Hero Here

Real Data Results Table

1. Speed, Kerf, Power – All Side-by-Side
2. What You Can Learn from These Results

Final Thoughts from Steve

Why You Shouldn’t Trust All YouTubers

Testing Beats Talking – Always Use Data

Also Check- 10 Best Free Circuit Simulators You Can Use online

 FAQs

1. How do I test kerf on my laser?

2. Does air assist affect beam results?

3. Should I upgrade from a 5W to 33W?

4. What’s the ideal laser for cutting plywood?

5. Can I reduce beam kerf manually?

Youtube Video  - 5 Diode Laser Myths That Just Won't Go Away

💡 Meet the Lasers

I pulled together four diode lasers, each from a different power tier. Here's our lineup:

🔹 5W – Sculpfun S6

A great budget pick and surprisingly effective on thin materials, but let’s see how it holds up against big dogs.

🔹 10W – Creality Falcon

Popular in maker spaces. Double the diodes, but is it really twice as powerful?

🔹 20W – Longer Ray5

A mid-high tier performer with a good reputation and decent speed. Good balance of price and performance.

🔹 33W – xTool P2

Absolute unit of a machine. Packed with six diodes and long-lens optics. Let's see if all that power translates to real-world results.

📊 The Testing Methodology

Let’s talk science — no guesswork here!

🔬 Power vs Beam Size

We measured energy density, not just wattage. This means: how much laser juice hits a specific square millimeter.

📐 Material Cut Test

Ran identical cut tests (70 mm/min to 700 mm/min, 10% to 100% power) on the same plywood sheets to ensure fairness.

⚡ Fastest Cut Test

Used a simple curve cut to measure not just speed, but smoothness and success rate at various powers.

📏 Kerf Test

Measured the width of the cut to analyze precision — a crucial detail often ignored!

🔍 Optics Matter

Kept air assist OFF and used manufacturer-recommended focus. If your lens or autofocus is off, your results might vary.

🧨 Myth #1: Laser Module Size Doesn’t Affect Power

🧪 The Truth: More Power = More Energy Density

Let’s not overthink this. A 33W laser simply pushes more energy into the material than a 5W. It cuts faster. Period.

📉 The Lie of "Same Output"

Some creators claim their 10W can cut like a 30W — nope. Our tests show almost 4x difference in energy density.

🔧 Myth #2: More Diodes = Bigger Beam

🔎 It’s Not About Diodes — It’s the Lens!

Beam size is more about optics and focal length than how many diodes are inside.

📐 Small vs Big Lenses

A 5W laser uses a short-focus lens to concentrate energy into a tiny spot. A 33W needs a longer focus to cut deeper. Result? A wider but more powerful beam.

✂️ Myth #3: Bigger Beam = Wider Kerf

📏 Reality Check: 5W Had the Widest Kerf

Surprised? Don’t be. That short focal lens creates a conical beam — cuts flare out more. Meanwhile, a 33W with a tighter, deeper beam creates narrower, more parallel edges.

⚠️ Myth #4: Adding Diodes Causes Power Loss

🔦 Stacked Diodes Do Lose Some Power

Yes, there’s a minor loss (about 16%) due to mirror reflection inefficiencies. But the net gain is huge — you're still getting massively more power than just a single diode.

📊 It’s Optics, Not Magic

Even with minor losses, stacking is efficient and gives stronger, deeper cuts. Saying “you lose power by adding diodes” is misleading at best.

📏 Myth #5: Higher Power Lasers Cut Deeper

🧠 Truth Bomb: It’s the Lens, Not Just the Power

Sure, more power helps, but cutting deep relies more on long focal lenses. That’s why the 33W can slice through 29mm acrylic. It holds its focus deep into the material.

📋 Real Data Results Table

Laser	Power (W)	Beam Size (mm)	Energy Density	Max Speed (mm/min)	Kerf (mm)
Sculpfun S6	5	0.06	Low	80	0.24
Creality Falcon	10	0.08	Medium	160	0.20
Longer Ray5	20	0.08x0.1	High	330	0.18
xTool P2	33	0.1	Very High	700+	0.16

✅ Conclusion

Diode lasers are incredibly powerful tools — but there’s way too much misinformation out there. By understanding how they work and what truly affects their performance, you can make smarter choices — whether buying your next laser or tuning your current one.

Knowledge is power… and in this case, cutting power 😉

❓ Frequently Asked Questions

1. How do I test kerf on my laser?

Run a simple square cut, measure with calipers, and compare to original dimensions. That difference is your kerf.

2. Does air assist affect beam results?

Yes — it improves cut cleanliness and depth but doesn't directly affect energy density or kerf.

3. Should I upgrade from a 5W to 33W?

If you’re cutting thick material regularly or want faster jobs, absolutely. The performance jump is significant.

4. What’s the ideal laser for cutting plywood?

At least 10W for clean cuts. For thick or multiple passes, go for 20W+.

5. Can I reduce beam kerf manually?

Yes, by adjusting focus, slowing speed slightly, and using tighter optics — but expect diminishing returns.