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[Backerther]

Hi 1967Brutus,


A great thanks for your understanding my way of thought about status quo of the trial run and modification plan to get her
more stable on the water at a bit faster speed.
Frankly speaking, I want her to be a bit faster on a basis of definite stability.!!!  Safety first in RC modeling.!
I have two countermeasures to cope with the above problems under progress in secret here.
Since I 'm not confident of them...

[1967Brutus]

I know what you mean, you want stability "regardless of speed" in order to eliminate the possibilities of "oopsies".
Sometimes that can be done, sometimes it is what it is, unfortunately.

If I had to guess, I'd say the CoG is a touch forward, which also leads to the "running wet". Very possible getting the bow out a touch higher will bring that stability, because IMHO it is caused by the lateral point of the boat being too far forward due to the bow not lifting properly.
Same like an arrow having its feathers at the tail end, a boat on the plane wants to have its resistance in the aft, not in the front. Lifting the bow a bit should increase that stability. At least, that is my estimation.

Of course you can lower CoG but usually that has other less desirable effects, like the boat becoming a bit like a bobble head when in displacement mode.

That usually is a bit of a compromise that I had to make as well when ballasting my Krick Alexandra.

[Backerther]

The pics for today is my analysis of effects of enhanced hard chines I applied to my Constellation in the trial run as I had done
with my1/32 Lindberg PT-109.    The result was so so....


1; Original hull of 1/32 PT-109 with the plain hard chines
2; The waves seem standing roughly along the sides of hull
3; I applied the enhanced hard chines in my style to the second 1/32 PT-109 built last November
4/5; It appears to me that the enhanced chines did work very well judging from the side waves arising from the chines,
     especially forming a neat long bow arch in each side.
6; adopted the enhanced hard chines again in my Constellation
7/8; The effect is ....So so....? at this stage....     I don't know in the very near future???
9;;What I call "enhanced hard chines" in the real boat
10; The enhanced hard chines applied to my Constellation.


Well then, the second trial run is coming soon that I do expect a better performance.!!!!

[1967Brutus]

As you can see in the pics, after the modification (hard chines) your PT-109 is riding much higher than your Constellation. Before the modification, the PT-109 was riding much lower, with more of the keel touching the water.

I still think, this is the basic issue: Too much displacement and not enough plane.

I do not know if that can be solved without compromising the "stance" (how the boat sits in the water when not moving). But I do think moving some weight aft will improve the boat's handling at higher speeds.

[Backerther]

Your comment appears to put much importance on a slight backward balance to improve the better performance to which I agree fundamentally.   In addition to that, I feel there are some other causes to have her a bit unstable....
I will check the one cause of them if improved or not this time on the lake.

[1967Brutus]

Your comment appears to put much importance on a slight backward balance to improve the better performance to which I agree fundamentally.    

As soon as a boat gets on the plane, CoG is the main parameter for behaviour, and the importance of that parameter increases with speed.
If CoG adjustments are not possible, trimtabs are an option, but they are ugly.

The exact shape of the chines (more specific, the angle at which they deflect the water away from the hull, horizontal or downward) affects the lift the boat experiences, this can also be used to adjust how the boat rises out of the water.

[Backerther]

The pics for today are the very diorama with 1/20 Constellation in "the life size natute" simulating the Caribbean sea...!!!!
It was very fine day today with a nice surface of the lake.   1m/s north wind which is ideal and perfect for scale model
boating.

[1967Brutus]

Beautiful!

[Backerther]

Thanks a lot for such a comment as the above that are short and complimentary ones.!!!!!  
I do always welcome such comments,1967 Brutus.!!   


Well then, pics for today are the shots of dynamic scenes in the second trial run in which stability was improved at higher speed
to some extent, though not completely satisfactory yet..
I myself have to remember that this model ship is a "RC workable scale pla-model" originally and was not born a true RC boat.
I should not expect excessively her to play like a true RC boat on the water at excessively high speed.!
In this sense, scale realism of sailing is to be much respected on the water.
Or it's so pitiful if I should intend and try to get her run so fast excessively like a runabout on the water...The real boat is just a wooden cabin cruiser with a fly bridge born before 1960, not the modern high speed cabin cruiser made of GFRP.


But third trial run is to be held early in the December after additional countermeasures are applied.


However, some pics below look comparatively fast and dynamic like a modern cruiser for her traditional classical appearance..... Anyhow she ran better in the second test than in the first test.

[Backerther]

This model boat I think is characterized by its top-heavy construction with high sides and a flybridge and lightweight if I
should regard as a RC fast runner.  Frankly speaking, it's a bit difficult to gain a reasonable level of stability though I am seriously
trying to improve it with some countermeasures based upon my past experience.

[Backerther]

I'm now renewing my mates of passengers aboard my Constellation in parallel with improving sailing performance.
The pics below are just my images of their locations and casts for them to play onboard.
Well then, I have to think about their dressing up having much advice of my old wife on what colors they would be suitable..

It's so enjoyable to do such thing of diorama compositions as the above apart from the mainstream of building the boat hull, isn't it.

[Backerther]

Some impressive and dynamic pics in the third trial run taken today which has been improved gradually by my tenacious study ..??
But dynamic scenes below seem to spoil the traditional and classic mood of Chris Craft Constellation 1956....
Yes,!! this boat needs no such a high speed ...???    Stability comes first, not fast!!!  
She is not a runabout.!!!  
In this sense, my Lindberg 1/32 PT-109 is well-balanced between stability and speed.  

[1967Brutus]

Beautiful!

[Backerther]

I'm so happy if I could successfully let you show a nice video in the very near future in which my Constellation ran stably to such a level that I was satisfied with....
I have still two ideas left to improve the stability to my satisfaction, or at least, compromise.....


Seeking the stable and scale-like sailing ...???

[Backerther]

Pics for today are from the 4th trial run though the still images aren't understood by you about what they are different from the previoius ones...


To conclude, she ran like a runabout that was not a image of old Chris Craft cabin cruiser....
The video of the trial run will be posted another day, which may show you a nicer improvement of sailing stability...!!

[1967Brutus]

As they say:"Video, or it did not happen..."

But the pics look absolutely good!

[Backerther]

 "Dohomo-arigatou" for your friendly comment "which" means "A great thanks" in Japanese,1967Brutus.!


A video I think is better medium to let others understand the status of motion of RC models, as you have
 often used in this forum.
I have been enjoying the motion itself of RC scale models so far in the field after their completions.


By the way, are you enjoying your gas-powered boat that is already completed after fully painted...???
I have missed the boat running on the water way recently...

[1967Brutus]

"Dohomo-arigatou" for your friendly comment "which" means "A great thanks" in Japanese,1967Brutus.!

There is no need to thank me for telling the truth about a beautiful boat...

By the way, are you enjoying your gas-powered boat that is already completed after fully painted...???I have missed the boat running on the water way recently...

I wish I was... but the situation is, that I am right now running an even bigger boat on the water, as my profession is that of chief engineer on chemical tankers. Unfortunately my employer also operates Bunker Tankers and right now I am placed on one of those, so basically we're running around with a lot of that sticky black stuff in our tanks.
And since it is now winter time on the North Sea, I am not really enjoying that... Although today we're a bit lucky and the weather is acceptable, but keeping that gooey stuff at a pumpable temperature is quite a challenge when the weather gets bad.

So for the next 2 or 3 months, no playing with tiny boats for me...

[Backerther]

I have understood the latest conditions about your RC boating hobby and your profession which was the same as my late
father who once served aboard a small inland cargo-liner as a chief engineer.


The video of the 4th day trial run was edited properly as attached below.
The 5th day trial run will be final at present configuration and 6th day trial will be resumed after changing some parts.




https://www.youtube.com/watch?v=m2K5CjkaTL0


 

[Backerther]

Pics for today are the introduction of new members as new passengers aboard my cabin cruiser Constellation.!!
The new members consist fundamentally of two families and their aunts totaling to 7.
This configuration is standard throughout a year except the summer season when some bikini girls may possibly enchant us by their nice bodies.

[1967Brutus]

except the summer season when some bikini girls may possibly enchant us by their nice bodies.

[Backerther]

Props available for my Constellation...
Left to right
1; Black one is a kit furnished 29mm two bladed that was ignored in my boat from the beginning!
2;The first one of 34mm dia used in my boat that I felt were a bit torqueful
3;28mm dia prop now in service as seen in the video below.. Soon the props will be replaced with the rightest one of 32mm dia
4;32mm dia prop to be installed with as the final setting for this boat and possibly the best among the 4 props

https://www.youtube.com/watch?v=ruDKXcsmrEk

[Backerther]

A detailing work has been fulfilled gradually ...
The pics for today are of a deck table as seen below that is placed beside two old aunts talking cheerfully today too...
Next is ...is...something like some beverage to be put on the table.
Making a kind of diorama on the deck is also enjoyable and indispensable to serve as a scale model boat building, isn't it?

[derekwarner]

Hi Kiyo...........

A little concerned about the stability    of that X-leg Mini-Table......the Constellation would only have to cross a low wake of another similar-sized vessel.....and the table & drinks would go helter-skelter across the top deck [whilst listening to the original Helter Skelter by Sir Paul] 


Derek

[Backerther]

Thank you for your good and interesting advice on my mini table, Derek!
I do think so... The table must be very unstable on our local lake ,especially at higher speed which I like.
I just put the table for creating some kind of atmosphere like to watch her who anchored on the lake....knowing the
contradiction to what you referred...
As for "helter-skelter", I did not know the word at all until you referred here...I just learned it very much in many aspects
from my English Japanese dictionary and related information in the internet.
Thank you for the interesting and informative humorous comment.!!
Your common sense is not always common to me, a Japanese and in this sense this forum is a useful for me to know
how the Westerners think about in each topic, matter and subject posted here.
This is a kind of so-called international friendship through the model boat hobby, isn't it ??