Topic: Berthing tug Yarra, Dutch style

[subdriver]

Hello Manxmann, Joe,

Thanks for your input, I appreciate that! However, and I am probably running the risk of being called a stubborn Dutchman ...  , here are some more pics. The first one is the forward deck with deckhouse and anchor winch placed according to plan. The second one with the deckhouse just about 16mm back. And one of the real tug. (The Tanunda is a sister vessel of the Yarra)





You tell me what's the wright position ... 

About the recesses in the bulwarks; Carrington Slipway in Australia hase build several of these tugs. Some have the recesses, some don't. I have come accross four tugs from that series; the Tanunda, Crowter, Maika Tora and Dretia. Two of those have the recesses, two don't. Apart from that, and one or two reels of towingline on the back of the superstructure, they are identical. I found only one picture of the actual Yarra, but that's not good enough to get any details or messurement from.

[radio joe]

Hi Subdriver, you know there's no right or wrong way there's only your way, it's your build and your doing an excellent job of it, it's purely my opinion but the first picture shows the forward end of the wheelhouse nearly in line with the aft end of the recesses in the bulwarks which matches the picture of the first comparison tug, if that makes sense, and given that most of the work carried out on a tug is on the aft deck I would have thought that's where the most room would be, my Envoy class tug has a very small fore deck just big enough for mooring and anchor handling, again just my opinion and not meant as a criticism of you work, do what you are happy with.

[subdriver]

Hi Joe,
Thanks again for your replay, and your complements. I see this as positive feedback and certainly not as 'putting me down' or anything like that.  You are right, everyone builds as he does, there is no wrong way. Unless you try to put the props above the waterline that is .. 

The thing is, there is no model out there that is 100% scale, from whatever manucaturer. And the bigger the 'oriental factor' is, the lower that percentage gets. On that point you can certainly see that Deans Marine puts a lot of effort into their models to get them as close to the real thing as they can get. If you really want 100% you will have to build from scratch from the original shipyard plans. But a model doesn't really has to be 100% scale, its the fun in building a model that makes the hobby. And I am having a lot of that with this one! 

[subdriver]

I have been working on a little 'sidekick'; the search light on the steering house with a super bright LED.







Amazing how much light you can get out of just one LED! The mini servo has been modified to rotate 2x 90 degree. A short test video; first half with the lighting in the room switched off. (for the second part; ignore the background..  )

https://youtu.be/ytOiM-A8oiU

[radio joe]

That will do nicely, we're lucky with the components we can get today, the closest you could have got to that back in the sixties/seventies would have been a 6 volt torch bulb probably bigger than your whole searchlight. 

[subdriver]

Another sidekick; the electronics-level:



S= Neuhaus soundmodule with Multi-Switch function (8 channel 3.2V 20mA max.)
R= Receiver
B= UBEC module
M= multi-switch 'amplifier' (6 channel 5V 500mA, 1 channel  5v winch forward-backward) with magnet-switch and power distribution (2x 7,4V motors, 2x 11,1V waterpump and soundmodule)

Under side:

[subdriver]

The hull is now finished with placing the sacrificial anodes:



And after spraying the hull in matt varnisch, and placing the propshafts, propellers and rudders this is the result so far:







Then I put al the RC stuff in the hull:



And complete with the 'electronics level' and batteries



Then I put her in my garden pond to check out the weight. There is still about 1/4 inch to spare, enough for the extra weight in the deckhouse. I think even a little extra ballast will be needed.

A video of the initial testing: https://www.youtube.com/watch?v=H-pkjqJzfco

I was planing a short trailrun, but unfortunately the Dutch weather prevented that .. later!

[Troy Tempest]

Looking great, hope to see it in the water soon

[subdriver]

I finaly had a chance to do a test run. Comments in the video clip:

https://youtu.be/-xp8VNR6NGY

Conclusion: She runs great! Steering is spot on, but needs a little less servo throw. I will set the throttle to a max of about 50-60%. That wil take her just a tad over the maximum scale speed, with enough pulling power, but no more 'powerboat speeds'...    Towing at full power would also result in the boat pulling itself on it's side. During the testrun a lot of water ran over the deck, only two drops inside. On the battery, spraid in through the not yet sealed portholes .. 

All in all a good maiden trip! On with the building   

[subdriver]

With all the power it would be likely to loose the superstructure, especially when towing. So now I can attach it firmly to the hull. On the front end it latches under a plastic strip:



The back screws on with two M3 threads :



They can be screwed in and out with the caps on the engine vent's:



I can lift the entire model by grabing the superstructure, that'll do I think ... 



I'm a 'Murphy's Law' kind of guy... ; better safe then sorry .. 

[subdriver]

Over the weekend i did some programming on the sound module. That ment taking a Youtube video with a big marine diesel, modifying the sound and trimming it to convenient sections. Then putting it al together in the software:



Explanation:
Run 'x' = running sound, iddle (0) to full throttle (4)
Acc 'a'-'b' = acceleration from position a to b
Dec 'b'-'a' = deceleration from b to a
Start and stop sequence at the top

The 'run' files are easy, tricky are the 'acc' and 'dec' files wich have to be programmed to run at the correct throttle positions.

All in al it sound ok, but I am not completely happy yet. Some files need some finetuning still. But it's a good start!

Video: https://www.youtube.com/watch?v=7V-zaCpJYbc&feature=youtu.be

[subdriver]

Ok ... it has been a while ...  Almost a year, I had some other 'high priority builds' to complete. But now there is time again for the Yarra, so the build continues.

The hull has got some more paint on it since last time, this is how she lookes like now:





Having done this I am again eager to finisch the build, so ... to be continued!!

[subdriver]

Some progress. The bolllards have been placed, and the top hull has received a coat of matt varnisch. Furthermore:

Aound the bow the buffers have been glued. Pieces of rubber tubing with a lengt of 1,5mm brass rod inside to force them into shape. To them I also solderd chains to tighten them.



The 'tighteners' made from 1mm brass and pieces of 2x1mm tubing.



The first tires on the bow. There is a nice see-through on the tightners and chains.



Overview with all the tires.



The anchorwinch now sit's on the front deck. The bollards needs some rope, but then the foreward deck is finisched like this.



The afft deck is still a little nacked, i'm working on that 

[subdriver]

The afft deck also got it's parts.





On with the superstructure. I wanted to place the towing hook first, so that would give me the position of the hole to lead the towing line into the deck house. I want to make a winch there so I van varie the length of the towing line while on the water. But I was dissapointed about the finisch of the supplied towing hook, so I decided to make another one out of ABS and aluminium. The parts:


(for comparrison; I used a M2 bolt in the support, and the pins are 1,5mm)

Put toghether, with the Deans hook behind it.



and in its place on the deck house.

[subdriver]

While the paint on the tow hook is drying i made a tow winch inside the deckhouse. This enables me to varie the length of the tow line.



There is 2 meters of Dyneema line on the reel, thin but verry strong. If there is to great a pull on the line the spring compresses, thuss buffering the force. It is also a fail safe for letting the winch run to long. That would lead to a stuk line and the 6kg winch would pull things appart. When the spring compresses the switch on the left is released and the winch stops.

'Fail safe'-position: