I always wanted to build a coaxial helicopter with tiltable rotors, but there was always a problem with swashplates. Playing in LDD, I accidentally found a soultion to the problem. i found out, that two antennas fit perfectly in the grooves of the gearbox ring, enabeling me to make my own CV joint inside a turntable.

For the upper rotor I used the older helicopter CV joint and connected it to the lower one with 4 old links, which can have the pins inserted from any side.

After completing the main rotor assembly and motorized it, I found out, there should be some protection that stops the assemby from overloading when you switch the motor polarity. For that I used a sliding worm gear, which always rotates the rotors in one direction:

The M motor also powers a gearbox, which switches the power between landing gear and winch:

The rotors are tiltable via the control rod in the cab:

View of control beams and axle:

Rotors tilted left and right:

Forward and backwards:

Thats about it for functions. I may need some stronger springs for landing gear though

Video:

Edited November 7, 201014 yr by Zblj

Very nice MOC once again! Your productivity amazes me.. how much time did this one need, 1 hour? Love the clever use of the dual antennae. No LXF file this time though?

Your cat also seems to approve of it

By the way, it's spelled 'swash plate'.

Edited November 7, 201014 yr by jantjeuh

WOW, that is truely awesome, once again! Nice one

@ Zblj: As always, your MOCs are great! The counter-rotating blade mechanism makes this one special. You are "flying high" as one of the best Lego Technic MOCcers ever!

cool model

but; how does that "worm gear mechanism" works?

cool model

but; how does that "worm gear mechanism" works?

Its a simple worm gear which slides over 2 8 tooh gears. Those 8 tooth gears are also conencted to 2 16 tooth gears. Worm slides o any of the 8 tooth gears depending on engine rotation, but the 8 and 16 tooth gears always spin in same direction.

I like the realistic mechanical design very much, it looks like Ka-50.

very nice MOC.

This looks fantastic. The antennas are stronger than I would have thought from the picture and push the rotor pretty reliably. Is there any reason why the rotors cannot spin in the opposite direction though?

I also like the C&C music in the video.

Your productivity amazes me.. how much time did this one need, 1 hour?

My thoughts as well. This would have taken me at least a couple of months to build.

I also like the C&C music in the video.

C&C music? Isn't that Wagner's Ritt der Walküre? Made famous (again) by the helicopter scene in Apocalypse Now, I bet that's why Zblj chose it

Edited November 7, 201014 yr by jantjeuh

C&C music? Isn't that Wagner's Ritt der Walküre? Made famous (again) by the helicopter scene in Apocalypse Now, I bet that's why Zblj chose it

Cool, I didn't know that. It was used in the game Command & Conquer as well, which is where I had heard it.

This looks fantastic. The antennas are stronger than I would have thought from the picture and push the rotor pretty reliably. Is there any reason why the rotors cannot spin in the opposite direction though?

I also like the C&C music in the video.

My thoughts as well. This would have taken me at least a couple of months to build.

Thanks. The reason they dont spin in other direction is to prevent them from overloading when switching motor polarity.

Truly amazing MOC!

I never expected to see that kind of rotor in one, to be honest - what a great work you did there

Some neat solutions here, well done!

Very nice Helicopter... It could be cool to MOC LEGO parts with helicopters like Picooz or NIKO...

[bUMP]

neomomonga made this "Lego Technic Coaxial Reversal Structure Sample"

to use a Lego Technic Differential instead of a Technic Turntable:

I've seen prettier helicopters, but the concept of the dual rotor system is very cool and technically interresting.

Hi

regarding your furst post: If this is what you get n mind "accidentally" i do not want to know what you will get if you really try to figgure something out. That is a really cool helicopter with uniquefunctionallity!

Dino

Very cool moc!