How to Sharpen or Modify a Boat Prop

You can sharpen a smaller boat's propeller on your own.

Properly sharpening or modifying your boat's propeller can increase performance and reduce the amount of vibration on the boat's engine, drive train and radio. The less vibration these areas of the boat experience the longer they will last. A properly sharpened propeller also will reduce "prop walk," which is the tendency of the boat to pull to the right in response to the boat's operator attempting to turn the boat left. A professional boat mechanic should sharpen a large boat's propeller. However, the owner of a small radio-controlled boat can sharpen or modify the propeller on his own with the proper equipment.

Things You'll Need

• Black marker
• Dremel tool
• #250 wet sandpaper
• Sand paper oil
• Propeller balancer
• Fine file
• Polishing oil

Instructions

1. Clean off all of the rough production marks on the propeller with #250 wet sandpaper. You also can use a Dremmel tool if you prefer. Keep the sandpaper wet with fine oil as you rub to properly smooth out the rough marks you find.

2. Use a smooth file to sharpen the leading edge of the propeller. Make the propeller as sharp as you can to maximize your boat's performance. You should sharpen from the base all the way out to the tip. Try to make the sharp point as even as possible along the edge of the propeller to avoid straining your boat's engine.

3. Use a file to form a 90-degree angle between the blade surface and the propeller's trailing edge. Connect the propeller to a balancer and spin it around. Look to see which propeller blade ends up at the bottom after the spinning stops. The bottom blade is the heaviest. Mark it with a black marker. File down the back side of the blade to a point where you believe it is more even with the other blades on the propeller. Continue to repeat this process until the propeller stops at random points without one of the propeller blades being directly at the bottom.

4. Detach the propeller from the balancer and reexamine it for any marks or rough spots that need to be smoothed out. If you find any, use #250 sandpaper to remove the marks. Put the propeller back on the balancer to ensure that each blade weighs an even amount. Repeat Step 3 if you need to modify one or more blades.

5. Polish the front propeller's blades with a Dremel tool and a propeller polishing product.

References

• Model Boat Power: Propeller Balancing
• Hobbico: How to Balance a RC Boat Propeller Using Your Precision Prop Balancer
• RCBoat.com: Prop Tech Notes

Resources

• Read this Article in Spanish