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Author Topic: Why a Model Tug Towing loads so SMALL  (Read 7637 times)

craftysod

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Re: Why a Model Tug Towing loads so SMALL
« Reply #25 on: June 02, 2009, 11:18:02 PM »

Have a look at the Alfold show pics buy Ron.
There is a massive tow by a tiny tug,the pics dont do justice how big it really is,
oh and i want one of that little tug,who owns it,named Tracey
Mark
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ray123

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  • mary marie cygnus gm33
  • Location: southeast england
Re: Why a Model Tug Towing loads so SMALL
« Reply #26 on: June 03, 2009, 07:37:50 AM »

hi craftysod  the guy is a member of our club   the tug is from waveley models  g.r.p hull  14inch powered by a 400 motor 

(dont know the name that it is sold under  'sorry') 

 the tow belongs to me & is 5ft x 2ft beam   & theres quiet a lot of drag ''there'' :-))  regards ray
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More Coffee

  • Guest
Re: Why a Model Tug Towing loads so SMALL
« Reply #27 on: July 12, 2009, 08:02:21 PM »

Just use a floating dock..


Lets say the dock is comprised of a series of 45 gallon plastic drum's...each drum when full of water will weight approx 480Lbs... just fill a few drum's full of water and yer off ..


Now Has anybody calculated what a 200,000 ton ship weighs when its in the water ..yes it displaces 200,000 ton of water ..but she should weight less in waterthough not sbmerged..Im trying to remember high school and Archimedes Principal here ..
u
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chrise

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Re: Why a Model Tug Towing loads so SMALL
« Reply #28 on: July 13, 2009, 11:12:26 AM »

Just use a floating dock..



Now Has anybody calculated what a 200,000 ton ship weighs when its in the water ..yes it displaces 200,000 ton of water ..but she should weight less in waterthough not sbmerged..Im trying to remember high school and Archimedes Principal here ..
u

I always thought that if it floated & displaced 200000 tons of water then it weighed 200000 tons & that is why it displaces 200000 tons of water. I am not sure which Archimedes principle you are referring to.


Chris
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Navy2000

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Re: Why a Model Tug Towing loads so SMALL
« Reply #29 on: July 13, 2009, 11:45:25 PM »

The biggest thing here is to get the proper set up for the tug that you have. I have seen many tugs of the same size and be so far apart in what they could handel. Like the modified darby tug that I had the (Goliath) I had two Pittman servo motors that at 12 volts turned 3500 RPM's and I used the 3.5 inches kort nozzle prop made by prop shop that is what gave me a total power of large bollard pull that I had. This also helped me to push or pull large size barges. I am sure that I could have done more than I did but never tested it out. Now the same motor and prop of the same size with out having the kort nozzles in a Brooklyn tug a friend of mine was able to get about 8.5 pounds of bollard pull on a fish scale. I had one member of my club that had a Sequin tug and was only able to get about 1.5 pounds of pull. It all comes down to a good set up with your model, now all models can not be great with lots of power some tugs just will not allow it do porp size and the RPM's of the motor and also the pitch of the prop. For tug boats I tend to buy my props from Prop Shop and if they have two different props that are the same in Dia. I then will get the one that has the most pitch to it to help out with the pulling power. I also think that speed controls also play a small factor in all of this as well. Not all speed controls will deliver all the volatge that we all hope that they will.

Duane
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