Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Yachts and Sail R&D: => Topic started by: Rakiura on October 07, 2010, 04:34:11 pm

Title: Grand Banks Schooner and sail control & servo access.
Post by: Rakiura on October 07, 2010, 04:34:11 pm
The answers to the questions I am about to ask have most probably been dealt with somewhere in this forum, but as a newbie, please forgive me if I am retreading ground already covered and please point me in the right direction.

I am about to start fitting out a hull of a Grand Banks Schooner from Kingston Mouldings, UK. I intend to fit it with R/C and it will have 3  headsails as well as main and mizzen gaff rigged sails. Can anyone point me in the direction of how to control the total 5 sails, presumably with multiple winch/servo combination. I currently have two R/C sloops but each uses a single sail winch for both main and jib together - 2ch radio for sail and rudder control. But clearly the GBS will need to be a more complex arrangement.

My other question refers to cunning ways to disguise and keep water tight, a deck opening to service the R/C gear. The deck layout has small cabin and hatches as well as a poop deck taking up about 40% of the rear of the hull i.e. the deck steps down to the mid-to-fore deck region. Given the need for multiple servos/winches, I'm thinking I do not have enough deckhouses to lift as access, and even then it will be tight openings. Therefore being able to remove a clear section of deck is the other method. I don't want to invent large deckhouses and detract from the aesthetics of the deck layout as planned. Has anyone kitted out a boat such that a section of deck is routinely lifted (and resealed) to service the R/C gear. I'm wanting it to be as discrete as possible so as not to detract from the overall appearance of the deck i.e the removable section is suitable blending in with the deck planking.

Any thoughts and assistance is most welcome so I don't set about reinventing wheels.

I have attached the thumbnail image for the GBS from Kingston Mouldings site, to give an idea of the boat.

Cheers

Rakiura
Title: Re: Grand Banks Schooner and sail control & servo access.
Post by: tigertiger on October 08, 2010, 04:52:43 am
I am controlling 4 sails on one sail arm servo, a fith would not be too hard.

Reply# 14, 15 here http://www.modelboatmayhem.co.uk/forum/index.php?topic=2716.0 show how I did it.

For advice on the flying jib and other riffing set ups I can recommend the book by Philip Vaughn Williams Radio Controlled Scale Sailing Models
Title: Re: Grand Banks Schooner and sail control & servo access.
Post by: Rakiura on October 08, 2010, 02:25:58 pm
Thanks for the information links. I am reading your posts on Mary J. Ward carefully.

I also found a system using port & starboard jib sheets to each end of a servo arm. Sheeting in on the starboard sheet loosens the port sheet as the servo rotates one way, and vice versa for rotating back the other way. The servo at mid point has both sheets loosened as if running before the wind. This way the clew of the flying jib is pulled across the luff of the jib (and its forestay) when changing tack, just as on a real ship. The article showed multiple headsails set to work on one servo.

Thanks for the suggestion on that book. I will follow up and get a copy.

Rakiura
Title: Re: Grand Banks Schooner and sail control & servo access.
Post by: Jimmy James on October 30, 2010, 08:52:14 pm
Rakiura
 Here is three of the ways I use to control sail on some of my boats ... One is for 1 sail servo controlling the main & fore sail only  the jib, stay sail & jib top sail are self tacking
 The second is for 2 sail servos , 1 controlling the main & fore sail and the 2nd controlling the Jib and stay sail , the jib top sail is self tacking
 Another way is to use a double sail arm on the servo as a push me pull you on the sheets ...this is also handy if you have over lapping jibs if you want to control the jib top sail you will need leads on the deck and on the forward shrouds or stays to get the proper lead

(http://s2.postimage.org/nXs4i.jpg) (http://postimage.org/image/1cm95b410/)

(http://s2.postimage.org/nXuzr.jpg) (http://postimage.org/image/1cmasugis/)

I have two threads in this section (Brigantine Freebooter & 18th Century Lugger ) these also have some diagrams of sail controls
Hope this helps you
Freebooter
Jimmy
Title: Re: Grand Banks Schooner and sail control & servo access.
Post by: meatbomber on November 07, 2010, 03:03:58 pm
for the overlapping jibs / stays'ls do you get enough travel with single purchase to actually tack the sail ? It seems to me you`d kind of restrict the sheeting to a pretty tight setting even if fully sheeted out no?
Title: Re: Grand Banks Schooner and sail control & servo access.
Post by: terryyacht on November 13, 2010, 08:05:49 pm
Hi
On my pilot cutter I used a sail winch under the deck behind the mast,
I ran a continuous cord from winch pulley, up a tube through the deck and ran the cord along the deck through eyehooks, just inside bulwarks to a pulley at front of deck, then back along other side and down through another brass tube through dack onto winch pulley.
The sheets were attached, two per sail, to the running cord as required, one each side.
As cord ran back that side sheet hauled in allowing other sheet out and on reversing the other sheet was tensioned, a sort of push pull system. This hauled sail around ok.
This worked very well controlling a main and 3 jibs using standard hitec sail winch.
If you want any details just let me know.
Regards
Terry
Title: Re: Grand Banks Schooner and sail control & servo access.
Post by: Landlocked on November 13, 2010, 10:20:32 pm
Terryyacht's system is very similar to that in use across the pond by Andrew Charters and myself.  Hitech's sail winch provides enough travel until you reach about 1 meter LOD.  RMG's 280 line will work up to 2M LOD. 

Be sure to attach the forward turning block to elastic to keep the winch from throwing turns.

The flying jib can sheet directly to the moving loop, the changing lead angle is not a big problem.  The inner jibs/staysail can lead through turning blocks.

Pictures of our schooners during the recent US Vintage Model Yacht nationals at http://cheerio.zenfolio.com/

Landlocked
Title: Re: Grand Banks Schooner and sail control & servo access.
Post by: terryyacht on November 27, 2010, 07:41:22 pm
Hello again
Yes, I forgot to mention the forward pulley of the deck running line was spring loaded to ensure tension is kept on the winch pulley.
This is essential to stop the line coming out of it's groove.
On my One meter the return sheet , ie on the unloaded, slack, side , is of black elastic which keeps the tension on the winch drum all the time.
Some lovely models on your site, I especially love the old schooner just leaving harbour.
My club site is www.nottinghammodelboatclub.co.uk  there are a number of different boats on the gallery.
The sail section of the club is I am afraid getting smaller as we get older but we do sail a number of different craft from Micromagic to 10 raters
Regards
Title: Re: Grand Banks Schooner and sail control & servo access.
Post by: roycv on January 01, 2011, 11:24:40 am
Hi all, a friend of mine built the Grand Banks schooner about 10 years back now, I did note that she is a bit tender in the wind, so I should make the 2 staysails easy to remove for windy conditions.

I have the hull and have drastically altered it and the type of boat that she is.
I have deepened the keel by about an inch, and increased the freeboard by 3/4 of an inch.  Most things are done but I am not yet happy with controlling a square sail on the fore mast.  Will post when I am satisfied.
Happy New year,
regards Roy
Title: Re: Grand Banks Schooner and sail control & servo access.
Post by: Geoff Cropper on July 22, 2011, 06:48:25 pm
Hi,       This is my schooner from the same plans,  there's a winch line that goes round the quarter deck and back to the winch.     On this line is a small ring and all the sail lines are attached to this ring.           So all the sails move together.           Cheers,   Geoff