I have recently had some experience mounting the hobbyking 5030 propellers on the prop savers that comes with the 2mm shaft micro motors (e.g. hextronic 1811 2000kv or the Turnigy 1811 2900kv) on my micro quadcopter. A lot of people complain about the likelihood of the o-ring get loose and the propeller drops, causing a aircraft crash. Not only you might lose the o-ring and propeller (it could fly away anywhere!), the crash could damage the plane.
I had several incidences like this myself, since then I have been trying hard to find alternative propellers or prop adapters to replace the prop savers. Unfortunately the alternatives are either too expensive, or hardly available in stock. However there are many ways to securely mount the Hobbyking 5030 props on the prop savers, and I have tested some of them out and it works great!
The 5030 propellers I am talking about is this. The shaft hole is about 1.8mm wide.
Inserting Propellers directly into the shaft
This is the easiest and simplest way. However you will need a 5/64″ – 1.9844mm drill bit. If you don’t drill it first, and try to fit these right out of the bag, you will either break the motor, the PCB motor mount or your fingers trying to press it on. Even if you manage to put it on by force, you will likely to break the prop around the shaft. There is a reason why these propellers are so cheap!
Taking the conus off the prop saver
This trick is from the hobbyking forum. it’s a little difficult to take the conus off. I did this with a shape knife. One of the drawbacks is this hack is permanent, once you have taken the conus off, you will not able to put it back. But it’s fine if you are only aiming to use this prop saver for this type of propellers.
Using smaller ID o-rings (ID – inside diameter)
I believe the ones that comes with the 1811 motors are ID 16mm. I have ordered some 11mm and 13mm, see which one is the best for my application. The o-rings are very cheap on ebay, so don’t hesitate to order different sizes to test.
A different way of tying the o-ring to the screws on the prop saver
With the original o-ring, I could also get it to work with this way of tying. It reduces the slacks and increases the resistance between the o-ring and the screws on the prop savers. I ran a couple of times with this setup, and the propellers stays perfectly secure.
sorry i don’t have a picture yet for this, will upload it as soon as i get one.
Using prop adapter
It’s the last thing I would do, is to order the prop adapter. Not only it’s heavy, and expensive, it’s could also introduce vibration to the boom (arm) if it’s not balanced. You also lose the advantages of the prop saver (minimizes the damage of the prop hitting objects in a crash). However you can be assured your props are safely mounted.