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[john44]

Hi guys , this question has probably been asked before but I
can,t find the answer I am looking for.
I am in the process of scratch building"Will Everard" and I would
like to fit a finbox, I can see on the various photo,s that the keel
fin is fitted directly behind the mast or seems to be.
Is that the correct fitting position? if not could someone please tell
me how to find the correct finbox position as I do not want to make
a hash of it.

john 

[Popeye]

A good rule of thumb method in respect of 1:24 scale barges is to position the perpendicular of the fins' leading edge between 3/4" and 1" ahead of the mast centre Line.

[/size] One additional position 1" forw'd  plus another 1" aft of the mast C/L should compensate for any Weather or Lee helm tendency.[size=78%]

[/size]If you wish to pursue this subject further 'google' AMBO (Association of Model Barge Owners) whose Secretary, Richard Chesney, is a wealth of information on all matters relating to Thames barges.[size=78%]

[/size]Good luck[size=78%]

[john44]

Thanks Popeye, the boat I am building is 1/35th -33" long minus bowsprit.

cheers

john

[john44]

With the info given to me by Popeye, If I have worked it out correctly from 1/24th
to 1/35th scale (I am far from being any good at maths) but The 1" dimension
should now be 3/4" and the 3/4" dimension should now be 9/16"
hope this is correct because that is what I am going to build the fin box to,
and cut the slot in the hull.

john

[Popeye]

Ahoy John 44.


I don't think you'll experience any problems with what you're planning.


My barge buddies and I are of the  opinion that the keel position is not too critical as long as the fins' leading edge is slightly forw'd of the mast C/L,.  The proof of the pudding, so to speak, is that our barges  perform similarly,  major handling differences  being accounted for by virtue of all-up weight, sail trim and the helmsmans skill.


I adopt the same principle in respect of all my sailing models and to date have not experienced any handling problems.


Have fun.

[john44]

Thanks for that Popeye, its all to do with, if its in the wrong place you will get too much
lee helm or the bow will keep diving etc. me thinks there is more to this sailboat
milarkey, I wonder if it will ever catch on? 

john

[Popeye]

Thanks for that Popeye, its all to do with, if its in the wrong place you will get too much
lee helm or the bow will keep diving etc. me thinks there is more to this sailboat
milarkey, I wonder if it will ever catch on? 

john

Don't forget to provide for additional positions in your fin box to cater for  weather and/or lee helm tendencies.

[john44]

Hi popeye,
I will make provision for the different settings.
Have you any photo,s of your set up, you could PM to me Please.
Do you fix the fin through the deck like a IOM
or just under the deck.

cheers

john

[triumphjon]

it would be good if we can all see your set up please popeye , i too am in the process of rebiulding a 1/24th scale coastal barge , and need to know where / how to fit the external keel . jon

[tomarack]

Hi,
      I can reccomend ivor bittle pages, where plenty of question about thames barge construction (änd others ) are mentioned.
http://www.ivorbittle.co.uk/

 greetings  Tom

[Netleyned]

AMBO have all the answers.

Ned

[georgo]

very helpfull...

author=Popeye link=topic=43883.msg443745#msg443745 date=1372777459]
A good rule of thumb method in respect of 1:24 scale barges is to position the perpendicular of the fins' leading edge between 3/4" and 1" ahead of the mast centre Line.

 One additional position 1" forw'd  plus another 1" aft of the mast C/L should compensate for any Weather or Lee helm tendency.If you wish to pursue this subject further 'google' AMBO (Association of Model Barge Owners) whose Secretary, Richard Chesney, is a wealth of information on all matters relating to Thames barges.Good luck

[dreadnought72]

And just a caveat -

If you measure the sails' area and determine the centre of effort of all the sails in order to fix the keel position, in real life this will not equate to the real centre of effort. It will be wrong.

That wee mizzen, stuck out at the stern, will tend to draw the CoE aft. It's small, granted, but it is a long way behind the CoE of the larger main, thereby pulling the whole equation backwards. That mizzen sail is more for steadying and steering than driving.

Given that, with the main motive power provided by the mainsail, topsail and foresails, I think the "move the fin forwards" brigade, (typing above and) mentioning fin locations near the mast position, have it about right.

Andy