[TC26] Icebreaker

[JoKo]

Hello folks!

I was not active for a while but I have now time to start my TC26 MOC.

For a long time I wanted to build a new boat with cyclorotor propulsion. This is a good opportunity to build a functional icebreaker. I started with the hull from 60368 Arctic Explorer Ship. Because it has a pointy end and a "motor well": the opening in the hull into which I will submerge my rotors. Then I built a twin rotor with the maximal diameter possible in the well and minimal length. I still need to set the two hull halves 10 studs apart to fit the rotors and hide the gap with dark blue panels. This pushed the hull length to 80cm, this is gonna be a beast! 

Cyclorotor? What is that? https://www.eurobricks.com/forum/index.php?/forums/topic/191154-moc-cyclorotor-tow-boat-voith-schneider-inspired-new-funny-prototype/&tab=comments#comment-3537717

It will feature a Control+ hub, two independent thrust vectoring rotors and should be as functional as possible for real-life icebreaking!

 

[Zerobricks]

Great idea, can't wait to see how it comes out!

[Aurorasaurus]

cool idea. is it gonna make small talk with people?

[Seasider]

Interesting boat, never seen that type of propulsion before.

Remember this is a technic competition so I’d avoid making a ship superstructure from too many System parts

[JoKo]

There is some progress!

 

[Aurorasaurus]

looking good. have you done any float and ice tests?

[JoKo]

On 12/8/2023 at 12:06 AM, Zerobricks said:

Great idea, can't wait to see how it comes out!

Thanks!

On 12/8/2023 at 3:51 AM, Aurorasaurus said:

cool idea. is it gonna make small talk with people?

It's not a feature for now...  

On 12/8/2023 at 10:12 AM, Seasider said:

Interesting boat, never seen that type of propulsion before.

Remember this is a technic competition so I’d avoid making a ship superstructure from too many System parts

The propulsion is inspired by the Voith-Schneider system. Common on tug boats but still some nautical-nerdy stuff. 

@efferman did a great tug with back in the days: https://youtu.be/OlZ1n3thJB8?si=v6NUSX96v6N4XHGf

8 hours ago, Aurorasaurus said:

looking good. have you done any float and ice tests?

I do frequent float test in my shower but I'll need something bigger soon for propulsion soon... And breaking ice is not on the table yet.

I'm facing a dilemma: The ship is gonna be too heavy and too top-heavy. So either I make it simpler and lighter or I add buoyancy and stability with outriggers and floats. I'm not sure what is gonna ruin it the most. On one hand it's gonna be my biggest MOC , I'd like to make it complex and make the most of the 4 motors allowed plus manual function for maximum playability. I have enough lego hulls to make it stable but on the other hand I'm afraid that it would look awkward. It looks nice and quite realist now I'm afraid to ruin it

 

[Zerobricks]

Any way you can reduce weight? Perhaps try with removing the crane and helipad first? Also chimnies and observation deck seem quite heavy and high.

[aFrInaTi0n]

The higher, the bigger the effect - so as Zero pointed out: try to work from the highest objects downwards to lose some weight.. 

[Seasider]

I think going multi-hull or pontoons would be strange for an icebreaker. I agree with others you need to bring down the centre of gravity on your model, it looks very vertical.

thanks for the link about the propulsion method, very interesting, I can understand why in scenarios when you need ultimate manoeuvreability it works well. All the tugs I’ve see in use have been traditional props. 

[JoKo]

On 12/11/2023 at 7:06 PM, Zerobricks said:

Any way you can reduce weight? Perhaps try with removing the crane and helipad first? Also chimnies and observation deck seem quite heavy and high.

 

On 12/11/2023 at 11:41 PM, aFrInaTi0n said:

The higher, the bigger the effect - so as Zero pointed out: try to work from the highest objects downwards to lose some weight.. 

 

On 12/12/2023 at 2:08 PM, Seasider said:

I think going multi-hull or pontoons would be strange for an icebreaker. I agree with others you need to bring down the center of gravity on your model, it looks very vertical.

thanks for the link about the propulsion method, very interesting, I can understand why in scenarios when you need ultimate maneuverability it works well. All the tugs I’ve see in use have been traditional props. 

Yeah the multi-hull idea is more like an accessory to help me dare try it in outside "dangerous conditions" but I still needed more buoyancy, ideally far away from the centerline... first thing I did was removing a Control+ L motor used as a servo for thrust vectoring the front rotor. I lost some maneuverability but it is still far better than with traditional prop and rudder. Then I added buoyancy with immerged brick blocks between the two parts of the hull, two air tanks below the front deck. I also added  a small 60373 fire boat hull turned upside down below the front of superstructure. it is decked to prevent air loss and compartmented to reduce liquid ballast effect. On top of that (bottom of the icebreaker) I built a flooded bulge that contains a metal technic crane hook and a metal technic counterweight. All this gives me a quite big air bubble trapped as high as possible, a neutral flooded area and extra weight as low as possible. I have two positions for each to adjust the center of gravity. 

With that I was able to keep the boat afloat and leveled with the crane but without helipad and no anchor winch. I keep them for display and play feature on the table or the floor.

I added a pneumatic system with a Control + L motor driving a small pneumatic pump. The motor also drives a worm gear mechanism with a crank driving the valve. I have seen that blowing air bubbles under the hull and ice could help with icebreaking. I first tested without valve and the result was far from impressive... that's why i made the valve mechanism to pump the air into the tanks and release pressure every 15 seconds. Still not great but visible at least and I used this mechanism to animate a little bit the boat: a minifig with binoculars on the observation deck sweep ~25° of the horizon with a 15 seconds cycle. And on water I can add a lightbrick warning light on the front deck that turns on when bubbles are released.

In the pure tradition of big floating Lego boats There are a few accessory vehicles that I made with as much Technic as possible.

I'm done building. I now have to tune the steering control and make nice pictures and video.

 

 

 

 

[JoKo]

Last night was the first snow and negative temperature where I live. So I could test real condition.

There is the video

 

And the final pictures

 

Edited January 8 by JoKo

[gyenesvi]

Love the video, it has a really cool vibe and good use of accessories :) The build itself it also a nice one, good mix of technic functionality with those boat hulls and some studded parts, I like the propulsion/steering mechanism, and the way it's done in the center of the hull split into two parts. Also, the way the technic panels complement the hull in the middle is a nice idea. The overall looks is pretty smooth, hard to tell at first sight where are technic panels used, and the overall detailing is cool!

[JoKo]

4 hours ago, gyenesvi said:

Love the video, it has a really cool vibe and good use of accessories :) The build itself it also a nice one, good mix of technic functionality with those boat hulls and some studded parts, I like the propulsion/steering mechanism, and the way it's done in the center of the hull split into two parts. Also, the way the technic panels complement the hull in the middle is a nice idea. The overall looks is pretty smooth, hard to tell at first sight where are technic panels used, and the overall detailing is cool!

Thank you! yeah, I tried to make the video not too long and boring. 

[2GodBDGlory]

Nice job! That's definitely one of the nicer Technic ships I've seen, with some creative functions like the cycloidal prop system, the working helm, and the bubbles/horizon scanning!

[nerdsforprez]

Just saw your video.  I love this entry and the amount of time that went into playing, errr... *cough* *cough* I mean... making the video.   Very good entry IMO.