Folding Prop ???
 

Hello I bought a Royal Power Soar 2 meter, that had a .09 glow engine on it. I am going to put my OS .15 on this glider but was wondering if I could use a folding prop ? has anyone ever tried a folding prop on a nitro engine? Thanks

Hello, I am also looking for Folding Propeller for OS .15LA RC Glow Engine. Suggested propellers are 7x5, 7x6, 8x4 and 8x5

Can you use a folding prop on a reciprocating fuel engine? Depends on the engine and spinner/prop. The engine must be smooth and the prop/hardware must be very strong. It is not done very often at all. The equipment for folders is available for electric gliders. Electric motors are significantly less shock (pun intended) to the hardware than fuel engines so it's up to the user to judge and employ safely.

http://www.espritmodel.com/spinners-...prop-nuts.aspx

It has been done but be EXTREMELY careful about standing in line with the spinning prop.

Also keep checking the hubs for cracks.

Yup I am sure its been done as there seldom in all of aviation anything that has not been done before.

All that da Rock and j.duncker has mentioned I believe is quite accurate and important but I just wanted to expand a bit on why a reciprocating engine is so much harder on propellors. It is not because of any additional centrifical force that most speculate on but instead it is the pounding a prop takes in the direction of rotation from the power pulses that all reciprocating engines produce. Single cylinder four strokes are hardest of all on props and it is why they often need double nutting to avoid loosing propellors clear off the prop shaft. Electric motors and turbo props exhibit zero pounding in this plain of rotation therefore the prop can be built lighter. You can see this in most electric props where the blade shank area just outside the hub is greatly reduced in chord to save weight.

It is this reduced blade shank that is reduced in chord that may not be strong enough to the torsional beating of a recip. So as already stated if you experiment choose propellors that have the widest blade shank and hinge you can find and for heavens sake keep your body and especially your face out of the tip path plain of the prop at all times, even for just a quick test.

John

Now we're getting somewhere on the warnings.

Buckner's advice is dead on (pun intended again). There is a huge load on the prop blade where it is being driven by the spinner. AND.... keep in mind that load is equally difficult for the spinner's driving structure. So....

When you're looking at spinners, look for adequate bulk and materials in the parts that are actually carrying the prop. You'll notice quite a lot of the glider spinners use smallish hardware and it's often lighter metals. Sometimes it's not metal.

I know that the spinner/prop sets I've used for my gliders all have bothered me since day one. My first impression when seeing the less than robust bolts used by the first setup was, "jeez, this sure wouldn't work on a glow engine." I considered retrofitting to larger bolts and have every time I've flown. Why haven't I? Because it's nice to have a weak link in the system to protect the more expensive electric motors. And that has been proven at the field.