Lunyee 4040 Pro CNC Review: Affordable Desktop CNC Router That Outperforms Expectations

Written By Evan Rhodes

Introduction: My First Encounter

I’ve tried plenty of desktop CNC routers over the years, so when Lunyee asked me to check out the Lunyee 4040 Pro CNC machine, I honestly didn’t expect much. It turned out this affordable DIY machine is smarter and easier to use than I anticipated. Unlike most router kits that arrive as a chaotic pile of aluminum extrusions and loose screws, the 4040 Pro came mostly pre-assembled. With a main frame made of four solid plates and just a few bolts, setup was quick and hassle-free—letting me dive straight into testing its precision, build quality, and real-world engraving performance.

First Impressions & Build Quality

Straight out of the box, the 4040 Pro feels solid and carefully engineered. The frame runs on V-slot aluminum profiles with proper linear rails—none of those flimsy trapezoidal lead screws you sometimes see on budget machines.

The Y-axis rides on linear rails with four rollers per side instead of three, giving noticeably better rigidity during cutting.

It’s a belt-driven CNC, which some hobbyists might side-eye at first, but the design actually makes sense. Belt tensioning is easier to maintain, the motion stays smooth, and extending the X-axis later only requires longer belts, cables, and a bridge frame—no need to replace the spindle or lead screws.

Putting it together took me around 30 minutes, though your time may vary depending on experience. The manual is thorough, with over 80 clearly illustrated steps, and it comes with a professionally translated English version—a nice touch you don’t often get in this entry-level CNC machine price range.

 

 

Stepper Motors, Spindle & Specs

The 4040 Pro normally ships with a 100 W spindle, but for this review, Lunyee provided a 500 W upgrade unit rated at 12 000 RPM. This extra power allowed me to push the machine a bit harder on materials like aluminum and hardwood.

The maximum working area is 400 × 400 mm, with a Z-axis travel height of 90 mm, which is more than enough for typical DIY projects or small-scale prototyping.

Each NEMA 17 stepper motor has an adjustable current knob on the controller board, and the control box is neatly organized with labeled wiring and dedicated ports for optional accessories such as a laser head, Z-probe, or offline controller. There’s no built-in display, but GRBL software like Candle connects seamlessly via USB.

Other thoughtful details include:

• LED indicators on every limit switch.
• A practical cable-management chain that prevents tangling.
• Clearly labeled connections for easy troubleshooting.

 

Easy CNC Setup & Calibration

Everything went together smoothly. The only real hiccup was with stepper motor locking. When power is off, the motors release tension—which is normal—but mine stayed unlocked during operation.

A simple G-code macro (OLL39 = 1) fixed the issue permanently.

Once the axes were homed, I had the machine running test cuts within minutes.

 

Cutting Performance Test

The first thing you notice when homing the machine is how smoothly it moves. The Y-axis glides effortlessly, and even at higher feed rates, the machine stays surprisingly quiet—far less noisy than my older Makita-based setup.

Here’s how it performed on different materials:

• MDF: Cuts like butter with clean edges and no burn marks. Best results at ~2–3 mm depth per pass, 10–15 mm/s feed.
• Pine / Hardwood: Requires lighter passes (around 2 mm), but no chatter.
• Aluminum: Achievable at 5–10 mm/s feed with shallow depth and proper coolant or lubrication.

After about 40–50 hours of cutting and engraving, the machine remained stable—no skipped steps, no belt stretching, no loose joints. The belt-drive system performed far better than expected for its price.

 

Software & Workflow

I primarily used Candle for controlling the machine, but any GRBL-based software works fine. Lunyee includes preset macros for homing and tool-height probing, which make the workflow faster and more beginner-friendly.

Design your toolpaths in Vectric (or Fusion 360), export the G-code, zero your workpiece, and start carving.

 

Upgrades & Expandability

One of the strongest points of the 4040 Pro is its modular CNC design. The X-axis can be extended up to 60–80 cm by swapping the side frame and belt set, which is ideal for users who outgrow the stock workspace.

Lunyee also sells compatible CNC accessories:

• Laser engraving heads (5 W–20 W)
• Higher-power spindle motors
• Stepper motor upgrade kits
• Clamps, tool sets, and dust-shoe attachments

This kind of expandability under $600 is rare in the hobby CNC router market.

 

 

Precision & Accuracy Results

For testing, I milled an MDF speaker divider, small wooden inlays, and aluminum nameplates.

All parts came out with tight tolerances and minimal post-processing—edges were clean and repeatability was excellent.

The results make it clear: for CNC woodworking, engraving, and light aluminum milling, the 4040 Pro hits a sweet spot. It’s accurate, stable, and approachable for makers and DIY CNC enthusiasts without feeling like a toy.

 

Pros & Cons

Pros:

• Rigid linear-rail frame with four-roller Y-axis support
• Quiet, fast, and precise belt-drive motion
• Straightforward 30-minute assembly
• Modular design with excellent upgrade options
• Clear documentation and well-labeled wiring
• Compatible with both CNC routing and laser engraving

Cons:

• No built-in screen or offline controller (software required)
• Requires a small firmware macro for motor-lock fix
• Belt tensioning takes a bit of practice on first setup
• The stock 100 W spindle handles wood and soft materials well, but for harder metals, the 500 W upgrade is highly recommended.

 

 

Final Thoughts

After dozens of hours using the Lunyee 4040 Pro, it’s safe to say this machine is far from a beginner’s toy.

It’s a serious entry-level CNC built with thoughtful engineering, reliable components, and room to grow.

Sure, it’s not perfect—nothing under $600 is—but between the linear rails, smooth belt drive, and expandable CNC frame, it stands out as one of the most capable desktop CNC machines in its price range.

If you’re looking for your first CNC router for beginners or planning to expand your maker workshop beyond laser engraving, the 4040 Pro deserves a spot on your shortlist.

 

Verdict: A budget-friendly CNC machine that delivers way more than you’d expect—quiet, precise, and ready for makers who want to do real work, not just play around.