Gemfan 7040 7" Tri-Blade Long Range FPV Propellers - Black (Set of 4)

Specifications

• Brand: Gemfan

• Material: High-Impact Polycarbonate (PC)

• Color: Black (Opaque)

• Diameter: 7.0 inches

• Pitch: 4.0 inches

• Blades: 3 (Tri-blade)

• Mounting Hole (Bore): 5mm (Standard M5 motor shaft)

• Center Thickness (Hub): 7.5mm

• Weight: ~7.9g (per propeller)

• Rotation: 2x CW (Clockwise) and 2x CCW (Counter-Clockwise) per set

Unlock New Capabilities (Project Evolution) The Mountain Surfer Cinematic Rig: Take your FPV hobby beyond the local park. Evolve your fleet by building a dedicated 7-inch cruiser! Pair these Gemfan 7040 props with a deadcat-style 7-inch carbon fiber frame, low-KV motors (like a 2806.5 1300KV), a reliable GPS module for rescue capabilities, and a 6S 4000mAh Li-Ion battery pack. This setup, driven by the efficiency of the 7040 blades, will easily allow you to scale mountainsides, dive deep valleys, and cruise for 15+ minutes on a single charge.

PACKAGE INCLUDED

• 2 x Gemfan 7" 7040 3-Blade Propeller (CW / Clockwise) - Black

• 2 x Gemfan 7" 7040 3-Blade Propeller (CCW / Counter-Clockwise) - Black

FREQUENTLY ASKED QUESTIONS (FAQ)

1. What do the numbers "7040" mean? The first two numbers (70) represent the overall diameter of the propeller, which is 7.0 inches. The last two numbers (40) represent the pitch of the blade, which is 4.0 inches.

2. Can I put these on my standard 5-inch FPV drone? No. These propellers are significantly larger than 5-inch props. If you put them on a 5-inch frame, the blades will instantly strike the body of the drone or hit each other, causing a crash. You must use a dedicated 7-inch frame.

3. What is the mounting hole size? The center bore is exactly 5mm, which fits the standard M5 threaded shafts found on almost all mid-to-large sized FPV motors.

4. What size motors are best for 7-inch propellers? Do not use standard 5-inch motors (like 2207s). For 7-inch props, you need larger stators with more torque to spin the heavy blades efficiently. Recommended sizes include 2806.5, 2808, or 3110.

5. What KV rating should my motors have? If you are running a 6S battery (standard for modern 7-inch builds), you should aim for a lower KV, typically between 1200KV and 1500KV.

6. Are these propellers loud? 7-inch propellers move a much larger volume of air at a lower RPM than 5-inch props. Consequently, they produce a deeper, lower-frequency "hum" rather than the high-pitched "scream" of smaller drones.

7. How much does a single 7040 propeller weigh? Each propeller weighs approximately 7.9 grams.

8. Are these good for aggressive freestyle tricks? While you can do basic flips and rolls, 7-inch quads carry a lot of momentum and are not meant for rapid, snappy freestyle ("bando bashing"). These props excel at smooth cinematic flying and long-range cruising.

9. Why choose 3 blades instead of 2 blades (bi-blade) for long range? Bi-blades are slightly more efficient for pure, steady-state forward cruising. However, tri-blades (like these) offer much better "grip" in the air, resulting in smoother turning, better handling in crosswinds, and less "jello" in your HD camera footage.

10. What material are these made from? They are made from durable Polycarbonate (PC), a highly flexible and impact-resistant plastic standard in the FPV industry.

11. Do I need to balance these propellers? Gemfan props are highly balanced from the factory. However, because 7-inch quads are often used for professional videography, some pilots choose to micro-balance them with tape to eliminate even the slightest microscopic vibrations.

12. Why are there CW and CCW propellers in the pack? A quadcopter uses counter-rotating motors to maintain yaw stability. You must place Clockwise (CW) props on CW-spinning motors, and Counter-Clockwise (CCW) props on CCW-spinning motors.

13. How do I know which one is CW and which is CCW? Look at the blade's leading edge (the thickest, most elevated part). The propeller is designed to spin in the direction where that leading edge cuts forward into the air.

14. What happens if I install a propeller upside down? Your drone will either fail to lift off or will fly extremely poorly, consuming massive amounts of battery. Always ensure the "Gemfan 7040" molded lettering is facing upward toward the sky.

15. Can I use these on a DJI FPV drone? No. The DJI FPV drone uses proprietary 5-inch quick-release propellers. These are standard 5mm bolt-on 7-inch props.

16. What is the hub thickness? The central hub is 7.5mm thick. Ensure your motor's threaded shaft is tall enough to fit the prop and the nylon insert of your M5 locknut securely.

17. Do these props come with mounting nuts? No, propellers do not come with hardware. You must use the M5 locknuts provided with your brushless motors.

18. Can I bend a crashed 7-inch prop back into shape? Yes, polycarbonate can be bent back. However, because 7-inch drones often fly long distances where a failure means losing the drone entirely, it is highly recommended to immediately replace any crashed or stressed propeller before a long-range flight.

19. Does the black color make the plastic more brittle? No. The pigment used in black polycarbonate does not compromise the structural integrity or flexibility of the blade.

20. Will these props draw more battery power than a 7035 prop? Yes. A higher pitch (4.0 vs 3.5) means the blade takes a larger "bite" of air per revolution. This creates more thrust and top speed but requires slightly more current (amps) from your battery.