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The Star45 Model Sail Boat A radio controlled R C Sailing Model

Kamis, 02 Juni 2016






The Star 45 is a 45" long hard chine hull; semi-scale model of the full-size Olympic Star. They weigh 12 pounds plus, have 12 inch beam. They are easy to scratch build and sail. Well suited for building by by the novice builder and by the skipper looking for a classic looking model to race.
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Daves musings about setting up and adjusting sails on R C model Boat

Sabtu, 02 April 2016

Dry sailing -set up.

Place the model in a stand. Head the model into them wind.

Things that can be moved, and adjusted: Mast step. Mast rake. Boom vangs. Shrouds. stays. Jumper stays. Head stay/jib stay. Sail shape - loose foot. out-hauls.

Attach the sails to the mast.

Set the sail winches in fully trimmed position while allowing sheets to be slack.

Stand the mast with standing rigging attached in the center step position.

Hook the jib swivel into the middle slot of the jib rack. {The jib boom needs to clear the mast.}

Connect the side stays to the chain plates and adjust so the mast is straight and vertical.

Connect the back stay to the back stay fitting.
The jib stay and back stay will need adjusting to set the mast in vertical position.

Move the out-haul of the sails along the boom to give the sails to have some "belly". Pulling the sails out along the boom flattens their shape. The belly (or shape) of the sails will be determined later and the sail shape will be determined by how windy it is.

Where you attach the sheets to the booms will take into account the type and adjustments available for the sail control. The booms should be full out (90 degrees to the center line of the hull) when the SCU is full out and then the booms should be just about over the center line when fully trimmed in. ( I see 10 degrees as suggested angle to center line). The length of jib sheet trimmed and the length of main sheet trimmed is a factor in setting up the sail control so the sails are coordinated properly when sailing. The SCU handles a much longer main sheet than the jib sheet. The use of jib traveler and mainsheet traveler can help position the sails when fully trimmed in. Unless two servos (SCUs) are used a single SCU has the task of coordinating the positioning of the jib and main.

Turn on the R/C and run the SCU.
Test out SCU setting with the sails full out and fully trimmed.

With the mast set up and sails adjusted roughly in position it time to launch and sail.
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Setting Sail on the water.

Before launching TURN on the radio on the boat. I have seen many models set loose to sail with the on board receiver and sail controls not tuned on and very unhappy skippers watching as their model sails away towards the horizon.

The initial rigging and sail settings are based in getting the model to sail a strait line while close hauled (sails trimmed in) and sailing up-wind.

Properly trimmed the rig will allow the model to sail it self in a straight line with just a minor tendency to "round-up" (i.e. sail itself dead into the wind). If or example you find you are constantly pulling the tiller (i.e. rudder) hard over to pull the model back on course to keep from heading in to the wind your model has weather helm which means your mast and jib must be re-positioned. When tacking if your model stalls into the wind and wont tack? Try different rig setting.

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Setting Sails
The art of tuning the rig on a sail boat is detailed in books written for racing yachts and boats.

"DINGHY SAILS"
by Jeremy. Howard-Williams

"The Best of Sail Trim:
A Selection of Articles from Sail Magazine"

"Sail Trim: Theory And Practice"
by Peter Hahne

My observations and commentary on tuning are from an amateur and are at best suggestions not professional advice.

Observation Number One!!
Model sails that are single panel loose footed sails rely on the shape of the sail established by the gap between the boom and the foot of the sail. Model sails with "shape" sewn into the sail fabric still are loose footed. Also the lift of the boom also factors in determining the shape and performance of the sails.

Hauling a sail into the center line and at the same time pulling down on the sail can flatten the fabric and kill the sail shape. I like to use travelers to position the sail to the desired point near the center line. Then you can set the point of maximum driving force and not wreck the sail shape.

On a big boat the skipper can changer the suit of sails to match the cut of the sail with the wind conditions. In the case of a model a skipper can change where the out-haul is along the boom, light air adding belly to increase the drive, heavy air pulling the sail out further changing the sails airfoil.

The jib and mainsail work as a system. A skipper has all manner of combinations that may be set relating the two sails. If the models did not have jib clubs they could overlap the mainsail. So model sailors have to adjust the "slot" between the jib and the main to get the maximum driving combined air foil.

In heavy air you may want to close the slot and ease the main so that the jib slightly back-winds the main to help the model sail flatter (less heeling).

Dont forget on a model it is easy to rake the mast fore and aft to trim the sailing characteristics to match wind conditions.
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A digital camera can be a terrific diagnostic tool for seeing what is happening on your model. You can look at pictures and spot misadjustments. Bends in mast, wrinkles in sails etc. Does you models mast rake forward down wind? Is the back stay bending the top of the mast. How are the jumper/jenny stays adjusted do they balance the tensions between the jib and the back stay?
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The late Manny Costa of RI always stressed, change one thing at a time to see what changes. He also stressed sailing a pair of models. One model being tuned and sailing against the second to see if the single adjustment improved performance.

Round-Robin racing in pairs is an excellent way to evaluate how your model performs.
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C C Redline 41 Review

Kamis, 11 Februari 2016



There has been no shortage of fanfare surrounding the launch of the new C&C Redline 41, and with good reason. This all-new design traces its commercial pedigree back to  the fabulous line of racing/cruising yachts designed by the legendary team of George Cuthbertson and George Cassian, The history of C&C Yachts is convoluted so I wont go into the details here, but you can read all about it on the Internet. Back then I was still a kid and a huge fan of C&C boats and thought they were all designed by the two Georges, but in fact much of the credit for the excellent design work belongs to Rob Ball and Rob Mazza as well as other talented designers that spent more or less time at C&C.

That was back in the heyday of yacht building in North America. By the mid 1990s the company had fallen on hard times and was taken over by Tartan Yachts, which produced a series of boats under the C&C name that were designed by Tim Jackett. Those were, in my opinion, okay boats but not quite in the same league as those designed by Ball, Mazza and the rest of early C&C design team.  In 2013 the C&C assets were acquired by US Watercraft, which is based in Warren, Rhode Island.

Finally, C&C, which suffered the same stormy weather as all the other sailboat builders in America over the last fifteen years, has found a favorable wind. It will be a surprise to me if C&C does not return to something akin to its former success. In addition to C&C, USW owns and manufactures the Alerion, True North and Carolina Cockpit brands as well as Waterline Systems. They are also a licensed builder of several J/Boat and Farr models. They have enlisted the venerable Barry Carroll to manage the C&C brand and Mark Mills to do the design work. Its hard to imagine a more capable gang to carry on the C&C name.

The Redline 41is intended as a racer/cruiser with the emphasis on IRC racer.  Here are some numbers:

LOA:  40.7
LWL:  35.4
BMAX: 12.13
Draft:  8.2
DISP:  15,100 LB
BAL:  7,232 LB
Calculated Sail Area: 891 SF
D/L:  152
SA/D:  23.3
BAL/DISP:  48%

Wire frame drawing shows a moderate displacement hull with firm bilges, narrow waterline beam, long overhang aft and no chines. 
I visited the C&C web site (www.c-cyachts.com) and found all of the photos for this article, including the beautiful wire frame drawing that gives us a pretty good understanding of the overall proportions of the boat. So beginning with the hull, we see a very clean shape with a narrow waterline beam and minimal wetted surface. Notice the slightly raked stem and the longish stern overhang. I like the raked stem for aesthetic reasons, and the long overhang aft provides reserve buoyancy when the boat is pressed, leaving a clean wake.  Notice the distribution of beam, its been pulled in a bit at the transom and there is plenty of flare in the hull in that area. Up forward, the bow is fine, with just a bit of hollow in the waterlines, and the knuckle is placed just above the waterline . This is going to be a slippery and well behaved yacht on all points of sail.

Driving upwind. notice the clean release of the wake off the transom. 


The keel consists of a cast iron vertical fin mated to a lead bulb. The bulb is an inverted "U" shape in cross section. This helps get the center of gravity (CG) as low as possible but does generate more turbulence than a more symmetrical torpedo shape. Im sure the Mills team analyzed this trade-off and decided that the benefit of the lower CG outweighs the cost of the higher turbulence.  The rudder is a deep, thin blade that should provide good control. With a displacement/length ratio of 152, the 41 isnt going to be a downwind planing machine but should surf along quite nicely on races such as the Transpac.

The IRC rule encourages moderate displacement and high-ish freeboard. This 41 is not equipped with an anchor locker or bow roller, but it sure is pretty.



Notice the inboard and outboard tracks and barber hauler.  


The cabin trunk is low and aerodynamically sculpted. It is relatively narrow amidships, leaving wide side decks and plenty of room to locate the jib tracks well inboard. Racers need tight sheeting angles. Notice that the forward end of the trunk is fairly wide, leaving very little side deck in this area. This was likely done to provide headroom in the head and forward cabin. The cockpit design is a nearly perfect for a racer/cruiser. The seats forward allow for headroom in the quarterberths and offer some comfort for the crew. The mainsheet traveler is located on the cockpit sole, with the sheet led to a pair of winches at the aft end of the seats, Admirals cup style. The photos show a recess in the open transom and I noticed in one of the renderings on the web site that they were at least thinking about a fold-down panel there that would serve as a swim/boarding platform. I dont think its necessary for cruising since the recess provides enough of a step that boarding from a dinghy wouldnt be a problem.


Sensible deck layout and reasonable accommodations for a racer/cruiser



The rig is pure raceboat. The mast and boom are carbon and so is the retractable bow pole. The chainplates are out at the rails so jibs are limited to about 105%. The boat has inboard and outboard jib tracks and barber haulers. This will allow the trimmer to dial the jib in perfectly. There is apparently an option for a short permanent bowsprit in lieu of the retractable pole. That would be a nice place to mount the anchor and roller, but since there is no provision for an anchor locker or windlass theres no point in trading the pole for the sprit.

The V-berth is snug and lightweight.


Going below, the accommodations are exactly what I would expect from the builders of the Alerion, a tasteful blend of white surfaces and wood accents. You might wonder what all that wood is doing in a boat like this. It certainly harks back to the days of true racer cruisers that C&C once built. The layout is functional for racing and offers just enough comfort for coastal cruising. The V-berth looks small, a perfect place for the kids. The head is minimal for a racer/cruiser and is located forward of the main bulkhead with access from the forward cabin. This isnt a perfect arrangement but is acceptable, in my opinion, because the Redline 41 is a racing yacht with cruising amenities rather than a cruising yacht racing capabilities.

Basic but comfortable accommodations.


The galley is bright and spacious for a racing yacht.

Its nice to see a well designed nav station on the Redline 41

The Redline 41 is going to be a fast and fun boat to sail. As for cruising, its easy to envision spending a week at the island, on a mooring. People passing by will inevitably slow down and admire it, ask what she is and comment on what a beautiful boat she is. Its harder to envision this boat spending a month cruising in more remote areas where good ground tackle, sun protection and shallower draft are important. Its a racing yacht that can be cruised. As I mentioned earlier, I will be surprised if this boat isnt a huge success and a worthy successor to the legendary boats that C&C produced in its heyday.







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