Footy Brigantine HMS Larne - RC Groups
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Sep 13, 2009, 12:27 PM
meatbomber's Avatar
Build Log

Footy Brigantine HMS Larne

Hello Folks,

After Drooling over Brooks Pond Topsl Schooner and the nice Footy Privateer i`m trying my hand at scratch building a Footy Brig / Brigantine.

I`m using Delftship to develop the model and create the Templates for cutting out the fuselage panels.

The Templates were then cut out from thick cardboard to make a test prototype. Goes together pretty well
Out of fun i loaded the boat up to 500g total weight and floatet her in the kitchen sink. That weight puts her right about where i would like to have the waterline.
Hoping to get some ply tomorrow to start the prototype Hull.
i`m thinking of building a removeable deck to be able to switch between several rigs.
Last edited by meatbomber; Oct 05, 2009 at 05:18 PM.
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Sep 13, 2009, 01:58 PM
Registered User
nigelpheron's Avatar
Looks really nice. Always wanted to make a pirate ship Footy. I might just in a few months.

I see your using a "budget-core" for the materials. Speaking of which, does anyone here know of a "budget-honeycomb", and source? Like a cardboard, but in an end-cut version.

Sep 13, 2009, 02:43 PM
Damp and Dizzy member
Brooks's Avatar
All Right MB! Looks great. You could always carve a chunk of balsa or styrofoam for the stern. Styro worked fine with my Pamir, though it took a lot of primer to fill the rough surface.

Freeboard is a detriment to my bottle schooner (excess windage, which must be countered by a huge fin keel and also lots of wind for sail power). So a higher waterline would not hurt you.... Provided you can make a watertight seal between deck and hull, something I have yet to achieve on Aldebaran (the electric tape I am using in the interim works ok, but it'd be nice to have a real seal).

Don't be afraid to have plenty of sail on your squarerigger. I think most model boats are under-canvased. With squaresails, it is easy to reduce sail as the wind picks up, which makes sailing more fun for me since it makes it more real. Scale sails work fine on Aldebaran, Pamir, my bottle sandbagger, and my 2 freesailers. They did not work so fine on my bottle schooner, but that is because of the excess freeboard, I think. So there is no reason to reduce sails below scale size for the hull length, I feel.

I push scale sails also because then the proportions look right. I deviated from scale for the brig conversion of Aldebaran (too lazy make all new spars and sails for the foremast and rerig the forestays). The mis-proportions of what I came up with knaw at me like a sore tooth everytime I look at her :-). But, the brig flies a Pirate flag, and the story I'll tell is that the pirates scavenged the parts for the new rig from ships they had taken...which is actually plausible :-).
Last edited by Brooks; Sep 13, 2009 at 02:50 PM.
Sep 13, 2009, 03:25 PM
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Yellow Baron's Avatar
Looks real nice MB, can't wait to see her built and on the water !
Sep 13, 2009, 03:32 PM
meatbomber's Avatar

hull templates added

The great thing with the Delftshipprogramm i`m using to get the templates for the hull construction is that making changes is super easy
What do you say, just make the hull in total shallower or just pull up the knuckle line and thus reducing the volume below teh current water line ?

The freebord as is is about 3cm at mid deck. So not much more than the Kittiwake Footy that i have...and that one sometimes heels enough to put the edge of the deck underwater.

What i really like is that the hull will fit all the rigs looks wise... well maybe not the topsl schooner with the rakish masts... it`s a bit blunt bowed for that one... but at least there should be no bow submarining on thus hull
Last edited by meatbomber; Sep 14, 2009 at 06:32 AM. Reason: Hull template file wasn`t complete
Sep 13, 2009, 05:20 PM
Damp and Dizzy member
Brooks's Avatar
3 cm freeboard does not seem too much, I guess I was not gaugeing the photo well. How about waterproofing your current cardboard hull, adding sails, and sailing her as the test? You could make both hull types and see which one met your requirements before cutting wood. I did that once, just using paint, and got several voyages out of the hull. If you have a suitable pond, you could even dispense with the RC. Free sailers are lots of fun if you can get to the other side of the pond to pick them up.

The fast ships of the 1800's raised the knuckle line, giving them a lot of "deadrise," and making a triangular cross section below the waterline. Those are the fastest hulls, but don't have as much buoyancy as a more squared cross section. They also can't carry as much sail as the wind picks up. So, blocky hull for weight carrying and sail carrying, deadrise hull for speed in light winds....just like flying, one has to make tradeoffs :-).
I forgot to add the easiest cardboard waterproofing of all, clear packing tape. My friend taped his son's cardboard LST, and it lasted for months of pond time, including at least 1 cross-the-pond voyage :-).
Last edited by Brooks; Sep 13, 2009 at 06:42 PM.
Sep 13, 2009, 08:07 PM
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Yellow Baron's Avatar
Looks greast MB, realy does ! Are you using the free version of Delftship?
Last edited by Yellow Baron; Sep 13, 2009 at 09:19 PM.
Sep 14, 2009, 02:31 AM
meatbomber's Avatar
thanks! hope i can get the look in reality too
We could make it a group project if you want.. with your building speed you should have one of these hulls in about 2 hours !

Yea it`s the free version of delftship... the only problem with is is that the printing functions are disabled so i have to work around that with print screens and photoshop at the size of the boat and my screen it`s not a big deal as my monitor is wider than the footy long and so a print screen gives me still enough resolution for processing the templates... a big ship would be different.
Sep 14, 2009, 11:09 AM
Registered User
capt_redde's Avatar
Aaaarrrrr, lookin good matey!
Sep 14, 2009, 11:52 AM
meatbomber's Avatar
i`ve started with the lower volume hull..
The only ply i got was 1mm thick so a bit thicker than i wanted but oh well.. Due to the thick wood and the small size sheets i got i couldn`t get the forward part to bend as planned and i had to cheat a bit below the knuckle line. but so far i`m pretty happy with the results. Next up is closing the gaps (plenty of gaps) and then giving here a once over sanding and then paint. The Transom is done with 1mm depron foam as it was impossible to get the ply to bend into that radius.
Weight of the Hull so far 78g
Sep 14, 2009, 02:33 PM
meatbomber's Avatar
The hull is all closed up and the caulking is finished. I cut the deck open. The actual deck will come on top and form the lid. i`m thinking of making te deck modular, as in sail servos mounted upside down to the deck and the rest of the RC in the hull.. that should make it easy to
a) fiddle with the sail servo and sheets and also
b) with swapping of the deck you can give the vessle a new appearance and rig (if i ever make another deck )

I testfloated the new hull to check for leaks and it`s all dry also the waterline seems to be perfect at a weigth of 520.

Tomorrow i`ll give her a good sanding
Sep 14, 2009, 03:00 PM
Damp and Dizzy member
Brooks's Avatar
Looks great, now you can add shipwright to your extensive aviator/mechanic/plane builder resume' :-)
Does Delfship produce patterns for the complex curves of your ply planks, or did you have to figure that out?

I see epoxy coating the inside of the Depron. But you might, if you have room, stuff some styrofoam in the lazarette before closing the deck - if the stern got t-boned by a bone head motorboat driver, the change in trim as the lazarette filled might make it hard to tack. Your rear collision bulkhead would keep you from sinking, of course, but you might have to walk to the far side of the pond for retrieval once maneuvers became limited to downwind ones.
Last edited by Brooks; Sep 14, 2009 at 03:38 PM. Reason: more ideas and questions
Sep 14, 2009, 03:39 PM
meatbomber's Avatar
brooks when you look at the Rigs i posted above, are the yards shown at their true length ?
If not then how long do i make the yards? TLAR (That looks about right)?
Sep 14, 2009, 04:06 PM
meatbomber's Avatar
Yea Delftship is creating the plates of course there are very complex shapesand you can`t fully flatten them so there are mistakes in those but it`s close enough form purpose.. just around the bow there is a change from concave to convex and i couldn`t get the ply to conform to i had to change the curve of the bow quite a bit and make the plates fit in-situ.. i`ll think about the protection of the stern, i will have to make some change there anyway as the former isn`t reaching the bottom boards

If the footy experiment fails i made a model of Sultanas hull at 60cm so double the footys size and same size as your pondsailer just need to print and cut the templates
Sep 14, 2009, 06:09 PM
Damp and Dizzy member
Brooks's Avatar
On a conventional sailplan, the rig is "flattened" so that the spar length drawn = the true spar length. Thus, conversion from paper to wood is easy. On your samples, I don't know if the artist flattened the rig or not. It looks pretty good, so perhaps there is no perspective (non-flattened) error. You could assume flattened, and cut wood, or you could add a fudge factor (10-20%) to the length of the yards following the TLAR principle. The spars as drawn look ok to me, but lengthening them, and then cutting them back later if you choose, is easier than the reverse. Another reason to add 10% - you don't know what distortions occurred in printing, the sailplan as printed may be smaller than the artist originally drew. Also, it's hard to get a precise matchup of equivelent hull length - I ran into that with my bottle schooner, and would have done better if I'd increased the rig 10%, I think.

There were spar length vs hull length formulas used by naval contractors back then (to standardize naval designs and naval contracts). Private ventures deviated from formula all the time, though. So, pretty much anything that you like would be acceptable in the sense that someone somewhere sometime did it like that for a real ship.
I fully expect your footy to succeed. My bottle schooner works, and the hull is only a cartoon compared to yours. The only 2 stipulations I impose, for guaranteed success, are a) that you don't put all the sails on one servo b) you use a big enough keel.

The point of a) is that multimasted ships maneuver best when you can move the CE around by differential sheeting of sails on the separate masts. What I discovered with the bottle schooner is that I did not need to control both masts separately: I could move the CE around, enough, by leaving the jibs and foresail sheets non-rc (belayed permanently on a beat), and just rc-ing the mainsail sheet and the fore squares on the 1 servo I had for the sails. The foresquares are on the opposite side of the CLR as the mainsail, so I was not sure that combo on the 1 servo would work. But, the jibs and foresail, stuck on the beat sheeting, were enough to "fix" the foremast's CE enough to allow the RC main + fore squares to steer the boat.

The point of b) is that there is more windage drag aloft from all the spars and rigging than there is from the Bermuda rig of a standard footy. So, to counter the extra windage, you need more fin area down in the water. The increase of fin needed surprized me, when I built the bottle schooner - I doubled the footy fin area, and I was still woefully short. If you look at the bottle schooner black fin (final posting of the bottle schooner thread), you'll see how big I had to go to make her work to windward. It's quite possible a smaller fin would work; I did not fine tune the boat after she was sailing correctly because I moved on to sandbaggers and Aldebaran. I tried a 3x footy keel, and that was too small, perhaps a 5x would have worked. The black keel is probably 10x.

Examples of Concern - Fred violated b (My Mistake, I originally wrote a&b, I apologize to Fred) and his ship did not sail the way he wanted on it's maiden. But he can change his ship if he wishes. And of course, I don't know it all, Fred's ship may work fine, as is, once he gets more practice sailing her. The colonial schooner also violated a&b, and his does not sail well (as of last report). I violated b and my bottle schooner did not sail well until I remedied the situation. Multimasted models have a bad reputation, possibly because previous modelers did not understand a&b, I don't know. What I do know is that all Boyle's freesailing squareriggers worked fine, mine (free & RC) work fine now, and the principles are not that hard...any modeler could achieve success, as far as I am concerned :-).
Last edited by Brooks; Sep 14, 2009 at 10:27 PM. Reason: My mistaken characterization of Fred's ship

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