Have you wondered how to make 5-bladed rotor ?

[green dewback]

I have looked at quite a few helicopter MOC on Brickshelf, and i dont understand how they did the 5-bladed rotor (penta-rotor).

Ive googled for instructions to make this but to no avail.

TLG only make 2-3-4-6 blades for their helicopter, and 5 is a weird shape no official set or simple prop part can make.

Search for Hind pictures for some examples.

In most of the pictures the propellor shaft connection is well hidden, but i saw this wheel piece in one of them.

So I mimicked it and made this.

(the trick is to fill only 5 of the 6 holes in the wheel piece, its not a perfect penta-rotor but its pretty close.

Because its not secured, the angle will shift away as you play it.)

Give me some comments and/or any better method to do it.

Hope this will come in handy for others who like to build aircraft.

[Ralph_S]

The way you do it is pretty close to how I've been building five bladed rotors for years (long before brickshelf, eurobricks or flickr existed) and it's not unlikely that the Hind you saw is mine. Pretty good that managed to figure it out by looking at a photo, but there are a few tricks to it that you're probably not aware of.

Because I get asked how I do it quite often, I took a picture of the rotor hub on my Sea King

The trick to keep them from flapping all over the place is tu use black technic pins. They have more friction -especially old ones without a slit in the middle. In order to keep the blade attached to the central axis from flapping about, it's attached to a technic connector with axlehole rather than a technic angle connector #1. That they do have some freedom of movement is very handy in this case, because it allows me to fold the blades.

The hub on the Hind works slightly differently, because I used 1x6 technic plates with holes to attach the blades. In this case the blade that is connected to the central axis is held in place by the top wheel, which is rotated 90 degrees relative to the bottom one.

Cheers,

Ralph

Edited January 31, 2009 by Ralph_S

[green dewback]

Thanks for the tip !

I will do that later with my limited parts, really need to shrink my oversized rotor hub.

*edit*

borrowed the blades from coast guard heli, its too big and long for play, will shrink it back.

now the hub looks more pleasing, more tight.

Thanks

***edit*

final version

compact and easy to play as i like it

Edited January 31, 2009 by green dewback