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Old Jan 25, 2014, 05:10 AM
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The modified Dragon Force thread - DF65

This thread is the place where non racers, designers and builders can discuss and share their experiences, try ideas, challenge thinking and ask for advice.

I intended to use the standard Dragon Force as a benchmark for teaching and learning , using a DR as a donor boat or using components that match those of a standard boat.
Because my own project is an education based project any racing we do won't be to ISAF rules, but far more relaxed, port/ starboard, avoid collisions, windward boat over taking boat keep clear, water for obstrucion water, on the mark, the intention is having rules that can be explained quickly to those who have never sailed before.
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Old Jan 25, 2014, 07:32 PM
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Robert, I bought a DF as an introduction into what I see as a very sophisticated class. I,m a designer/builder at heart. The footy got me going initially but that boat is simply too small for most sailing venues I enjoy. So a bit bigger, I see as better. The DF covers many bases that are important from my perspective considering my interest in the RG65 class. A problem however is most in my area sail Vics and Solings; so there is a concern about diluting the fleets. Time will tell. As for new participants, we find they come from mostly, the existing big boat sailors. So to your comment about education, how do you rope them in ?
Richard
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Old Jan 26, 2014, 01:53 AM
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I can understand the fear of diluting the fleets but to that end there is no reason preventing mixed keels races and working out a handicapping system to level out the results. However the dilution and popularity of the other fleets is usually explained by the reasons you didn't join those fleets.

How do you rope them in? That is the easy bit, Mark, John and co have done that bit, they have designed a great boat that allows development into Rg65 for those who want to go beyond the box. The hard bit is capturing them and turning the "cool", "wicked" and "cors" into participation. I think having two boats one which you are prepared to lend out to anyone however young takes care of that. A successful first sail will put the boat straight at the top of a Christmas or birthday list and being prepared to sell on the lend boat wil grab some there and then. The final bit is being at the same place at the same time next week and being prepared to be enthusiastic and tolerant of enthusiasm.
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Old Jan 26, 2014, 02:19 AM
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Because my own project is an education based project any racing we do won't be to ISAF rules, but far more relaxed, port/ starboard, avoid collisions, windward boat over taking boat keep clear, water for obstrucion water, on the mark, the intention is having rules that can be explained quickly to tose who have never sailed before.
Commendable idea but still can be overwhelming confusion for newbie as well as the experienced, practice in understanding the basic rules & courtesies for good seamanship takes time.

One thing that has helped lot of friends is simulation sailing with on-line games and this one does good job and is free ,of reminding skippers as they play, there is even a practice area to get good idea of the basics and put them into practice without the competition beating you up .... just an idea !
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Old Jan 26, 2014, 05:10 AM
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Commendable idea but still can be overwhelming confusion for newbie as well as the experienced, practice in understanding the basic rules & courtesies for good seamanship takes time.

One thing that has helped lot of friends is simulation sailing with on-line games and this one does good job and is free ,of reminding skippers as they play, there is even a practice area to get good idea of the basics and put them into practice without the competition beating you up .... just an idea !
The intention is not to throw everyone into racing on day one but to build up the basics as per any RYA training scheme. I agree about simulators and have used them to good effect teaching Aircraft and Heli flying where speed and gravity are a bit more punishing.
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Old Jan 26, 2014, 08:58 AM
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Robert, You mention handicapping - do you know of a reasonably simple system ?
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Old Jan 26, 2014, 11:45 AM
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not off hand for model yachts but basing on the theoretical speed of a 1000mm boat at 1.8 metres per second ( derived from (sq root 1000/304.8 * 0.688) and a 650 mm boat is 1 metre per second ( sq root 650/304.8 * 0.688) it is easy to assume that if a 1000mm boat take 7 minutes 23 seconds to finish it has (in theory) travelled 797 metres. It is easy then to say that if a 650mm yacht takes 796 seconds or under to sail the same course it beat the 1000mm boat, 797 seconds is a draw and anything over is a win for the longer boat.

That would be a good place to start and then after keeping a series of race results it will become obvious if the adjustment need to be varied either way.

If it is simple racing then a 1000 boat needs to sail 9 laps and a 650 mm boat 5 laps. If that is too long a race see if the 1000mm folk are happy sailing 2 laps for the shorter boats 1


Post the lengths of the boats you race and I will work out the handicap for each
Hopefully that makes sense
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Old Jan 26, 2014, 12:23 PM
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That's all well and good, but on another RG65 thread someone posted a video of a DF showing a 1 metre Seawind a clean pair of heels. A Seawind is also one of the better kit boats performance wise. I think maybe you would be better handicaping the skippers on past performance.
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Old Jan 26, 2014, 12:42 PM
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Our two area clubs have used the Seawind as the entry level boat, but with rising prices ($250 went to over $450 for a boat + electronics) and the unavailability of boats because of the destruction of the Kyosho factory, it became difficult to get young people and their parents to put out that much money to enter the sport, particularly in the last few years with the economy in our area in such bad shape.

At our awards dinner last night we discussed the option of creating a DF class - because of its low cost of entry and its out-of-the-box ability to get on the water quickly without the delay of building. There was a proposal that the club buy a couple of boats - one for people to sail and the other to be kept in the box so if they liked it, to "hook" them one the spot by selling them a new boat at our cost.

The main problem is how to not obsolete our installed base of Seawinds - our largest class - while building the new class. Also we have the issue of not allowing the better skippers to take over the new class. There is nothing worse for a beginner than to be so far behind the winners they see no chance of success. Using a handicapping system may just be the way to do it. That and limiting the DF class to box stock boats with a sub class of skippers with less than some number of years experience.

Have any of you used the system where the slower boats start first with the faster boats have the second start at some calculated later time? This would seem ideal as it gets the beginners out of the way at the start and gives them the thrill of being "out in front"....at least for awhile. And with a possible cloud of beginners to thread through on the final leg, the better skippers may think twice about sailing in that class.

From experience we know that one boat is never enough. Once we get them hooked on racing a DF we know they will want to get faster/larger boats and also compete in other classes.

Thoughts?

Steve
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Old Jan 26, 2014, 01:47 PM
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Are you trying to get me into trouble on my own thread Martin? The DF rig design is packed full of power with a reduced heeling center and a wider range CM to CJ so it is easier to balance the boat for optimum performance. Added to that being able to use the unspent weight at the bottom of the fin and you have a boat that stays upright longer and goes faster as a result.

Apparently thes little rockets can still be wearing the top suit in an F4 :cool


Hello Steve

As I mentioned that formula is ony a starting point and would naturally adjust like the Portsmouth yardstick over a season. I have raced full size one design helm handicap, but the maths and explanation flawed me as it seemed to encouraged people not to sail ahead of a championship.

Certainly having stock box racing levels the playing field. With strict out of the box racing there is the opportunity to pool all the boats, each boat and transmitter is given a number so the owner gets there own boat back at the end of the day, by drawing numbers to pick a boat and allowing a short time to test the drawn boat and tweak/tune it accordingly, the better helms end up passing on their tweaking tips to others. The less experienced skippers would do well not to fiddle if they get a chance to sail the boat that won the previous race!

In respect of faster bigger boats, I am not so sure that there will be a huge incentive to move beyond RG65 and when one starts to realise how much that class has grown in the past 4 years, I can see RG65 enjoying the same explosion in popularity that other classes have enjoyed in the past. I literally could not find anyone to make a set of sails or supply a rig for my RG65 in 2010 but now everyone is showing an interest.
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Old Jan 26, 2014, 02:13 PM
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One thing I have noticed from my adventures with model aircraft is the sheer speed with which stuff gets tooled and produced out of China; simply fantastic value for money and of a quality that I know of leading scale modellers who no longer design or build.

We are all different and different things interest us, here is something I have started to put together; a scale model yacht with a LWL of 650mm. this one is a 30sqm Skerry Cruiser designed by Knudds and built by Uffa Fox

Scale 65?
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Old Jan 26, 2014, 06:57 PM
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We are all different and different things interest us, here is something I have started to put together; a scale model yacht with a LWL of 650mm. this one is a 30sqm Skerry Cruiser designed by Knudds and built by Uffa Fox

Scale 65?

A very good (internet) friend, Claudio D - who many are familiar with from his posts on RCSailing.net penned some lines for the RG65 Class that resemble the IACC lines of past America's Cup yachts. I had provided the lines to several persons (ahem ) who were going to build and sail to see how well the boat responded to the RG65 specs. Alas, no one has yet done the build (or they haven't told me about it) but there again is another viable RG65 design for someone who does some scratch-building. As noted, it has yet to be sailed in active racing, so starting out, all that could be promised is a "look-alike" hull profile.

Just another possible class-within-a-class
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Old Jan 27, 2014, 01:45 AM
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A very good (internet) friend, Claudio D - who many are familiar with from his posts on RCSailing.net penned some lines for the RG65 Class that resemble the IACC lines of past America's Cup yachts.
Hi Dick, here are those plans .... been on my bucket list for awhile, time to tick it off

Cheers Alan
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Old Jan 27, 2014, 02:58 AM
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My thoughts on scale models of this size it that the LWL ought to be 650 mm rather than the overall length. The long overhangs, stem and stern start to disadvantage the displacement calculations and therefore sail area.

With essentially vertically cut off bow and sterns the modern model yachts all miss out on the benefits of the overhangs which experienced professional designers considered essentially made for a more stable sea boat. Our models effectively sail in scale sea states that are never often below moderate to rough and could therefore do with a bit of assistance.

At 650mm lwl the Waterwitch displaces about 1.2 kg but I end up with a hull of 980mm on the deck with a 150mm beam. That isn't a huge model, it can use RG65 components but it would have a pond presence that it would be denied at 650mm over all with a lwl of 450mm.

As lwl rather than deck length is considered the effective determinator of hull speed it would be nice to race a 650mm LWL J class against the modern fold away Americas Cup boats. That AC would be 710mm on the deck 140mm beam and have a draft of 350 mm, which would be a lovely size model.
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Old Jan 27, 2014, 04:10 AM
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I have long admired Claudio's work, I can think of a few folk who could do with spending some time looking at the stuff he does.

Would anyone mind if one were to build off those plans (Adjusted to 650mm lwl) and whack a Dragon Force rig on it , just to see what happens.
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