RC Plane Prop Saver

Michael Torrie created a really handy tool to save your RC plane’s propellers from a spinning death on impact. It’s called a prop saver and it’s based on the “elastic rules, static drules” principle. Read on for pictures and explanation:

The following is a close-up picture of a prop saver:

It bolts on to your propeller shaft just like a normal propeller, with two hex nuts (which are barely visible on the left and right of the black plastic yoke). The black plastic yoke is made from an old propeller, with the blades cut off, and two screws drilled into it and, of course, coated with tape for good measure (find more info about the propeller shaft structure here). The tape provides a little bit of friction when you slide the new prop on the top. You then attach your prop onto the tip of the yoke with a rubber band, securing it to the screws like this:

The prop sits on the tip of the yoke, swallowing it slightly. The rubber band holds it to the yoke and delivers the rotational force to the prop like a normal nut would, except with a bit more elasticity. That way, the prop’s blades don’t take the brunt of a crash, but rather the rubber band, as this picture shows:

That’s one safe prop! You’d have to crash it pretty hard to break it, in which case the prop will be the cheapest repair you’ll make.

This approach observes the “elastic rules, static drules” principle by allowing the prop to give a bit, rather than statically absorbing impact forces. This same principle applies to just about every component that break easily.

11 comments to “RC Plane Prop Saver”

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  1. I just found a place that sells them here:


  2. http://Lance says: -#1

    Hey Dave, Lance here again. The website you listed…


    …says “Fit for 3 mm shafts”. Can you please confirm the HZ Super Cub prop shaft is 3 mm.

    Thanks again!

  3. I am not totally sure. I think the Cub might actually have a 4mm shaft. It’s bigger than the standard E-flite and GWS props that I buy at my hobby shop, so I usually have to drill the a bit wider with a 5/32″ drill bit. According to the Google units converter, 5/32″ is 3.9685mm, so maybe it’s a 4mm shaft.

    That prop saver from xushobby.com will probably not work with the Cub without modification. I only posted it as an example. If it is plastic, then you can bore it out yourself.

    Props are so cheap that I just buy new ones. I haven’t broken one in a couple months now. :)


  4. By the way, I buy the GWS 1080 props. I have to drill them to widen the hole, but they work great. 1080 means 10×8.

  5. http://Nick says: -#1

    so this eliminates the nose cone right…there’s no real way to attach the nose cone to the prop is there?

  6. If you’re referring to the “spinner”, then yes, you have to remove it. The prop adapter replaces it.

    If you’re referring to the “cowling”, then no, you can leave it on.

  7. How to the 10×8 props compare in performance to the stock SC props?

  8. I found 10×8 to be the best prop for the HobbyZone Super Cub. I compared 11×6, 10×7, 9×6, and many others. The best prop, money wise and durability wise, is the GWS 1080 Slow Flyer. They come in black and also in bright orange. They only cost $1.49 and are flexible enough to bend on those rougher landings, rather than break like the factory props.

    Doesn’t the Super Cub ship with 10×8 props from the factory?

  9. Yes. I didn’t know the oem prop is a 10×8 when I asked the question. Thanks for the quick response.

  10. System is excellent but I don’t know anuthing abour radio controling (rc).Where I can find more about it?

  11. the web sit you have put on here does not work. for me anyway i want to buy some but can not find any.

    i need 3.17 mm shaft size. found at hobby king but the shipping is out ragious like 12.00 dollars for 6.00 dollars worth of stuff.. bad bad

    help me find them if you will please thanks in advance Dan