Auto stering systems like vanes, Braine gear and weighted rudders were intended to prevent steering – their job was to maintain a heading to the wind. So subtle corrections rather than full steering, implying rather different rudder requirements. Radio boats tend to have rather more rudder than self steerers.  In either case, the really important consideration is balancing the rig so the boat will at least try to sail straight.

One thing about yachts is that they tend to not get stranded in the middle of a lake. If the air moves, so do they provided they don't have anything to add drag. Of course, having an island in the middle of the lake adds its own uncertanty. Being stranded is different to being stuck.

Edited By Malcolm Frary on 23/12/2019 19:31:52

Hi Dave,

The model yacht works exactly like a full-size yacht with the slot effect, and yes the jib and main are adjusted proportionally to achieve the same lift from the sail shape to propel the boat forward. It is also easy to sail goosewinged directly down wind with a balanced rig. Take a look at the Dragon Force RG65 if your looking for entry level yacht, these are very popular these days for racing 😀

The next level is the Dragon Flite 95 which I have currently.

Regards Ray

Edited By Ray Wood 2 on 23/12/2019 20:45:28

Hello Dave

I have been following the conversation on the other thread. As has been said already, the development and availability of radio control heralded a major change in model yacht sailing and racing. The sport side is now divided with RC having the much larger participation but Vane racing is still enjoyed by many and some will say this is the sport of the purist.

A vane can be very simple. As a teen I designed and built a 32" model yacht and there was never any thought of being able to afford radio gear. Me and my sailing mate at the time used a plastic gear on the top of the rudder stock and another gear fixed to the shaft of a vane. The vane shaft ran in its own tube just the right distance away for them to mesh. The gear was adjusted by lift the vane to disengage the gear and re-set in the position for the desired point of sailing. It was remarkable efficient but obviously had to be manual changed at each tack. The sophisticated vanes are linked in a way that one setting works for both tacks. This is not the same as "self tacking" as the yachts still needed pushing through the wind at the pondside in order to tack.

Yachts designed for vanes tended to have long overhangs at the stern so that the vane could be operating in clean air and not be back-winded by the mainsail. Mine didn't and it worked OK.

You have set yourself a challenge combining Vane and RC but an interesting one at that. If you are going to have steering connected to an RC servo it will have to be disconnected while using the vane. The boat could easily be one or the other but a bit more tricky to mix both. Or of course you could have two rudders and the vane settings adjustable by RC! I was thinking about this last night. Big yachts have autopilots controlled by a vane at the masthead and sail a course in relation to the wind direction and keep a track of their position by GPS. My Vane yacht probably sailed better to windward than I could have steered it especially at distance when it is hard to see exactly what is going on.

Yes, I can see a bit of a project coming on and some transfer of technology from big boats and model aircraft to sail around a set of way points.

So Dave I am genuinely intrigued.

Stranded mid lake would be a real problem for me as I sail off beaches and open harbours. I always start from the lee shore so the boat would eventually drift back to me. If there is no lee shore I don't sail and should probably go flying.

Tim R

Any sailplan having more than one sail uses the slot effect, even ones that do not overlap, like the Genoa. Genoas are rare in models because of the extra complication needed to make them work, and extra weight of the gear needed to achieve this, but do exist. Spinnakers also exist, but are rare for the same reasons. Properly set up, the single winch can do nothing but operate the sails in a co-ordinated way (they are both ties to the same piece of string). Some yachts have an extra "twitcher" servo to give some extra adjustment on the jib.

Sail plans that do not have a loose footed (i.e. they have a boom) generally have the lower pivot set back about 1/4-1/3 of the way back, and often carry a leech line. This all ensures that the sail keeps its intended shape, and a side effect is that once you have the wind blowing over the transom, goose winging will happen, probably whether you want it or not.

A kit is a good place to start, even if only to figure out where you would have done better. DF65 has been mentioned, Victoria is very good, and there is a host of 1M long sailboats at very low prices, all of which are a good introduction for somebody who is not scared of improving things.

A simple plan build is also good, a favourite of mine was a free plan in one of the magazines frm the early '90's called "Akela". It reappeared for some time as the "XL 25" on a Dutch site, but that site now seems to have expired. If I did download the plan, I have since managed to misfile it.

Hi Dave,

I am a member of the Vintage Model Yacht Group and have some experience of vane sailing with yachts ranging from 36R sized up to A class. There were a series of articles on vane sailing published in the Turning Pole, the journal of the VMYG a few years ago. I have scans of them and if you send me your email address by private message I will forward them to you,

There are free plans available on the web of an Ezi-build vane gear designed by Graham Reeves. I have attached a photo of the one I built to his drawings.

There is a link to the plans on the Llandudno model yacht club site here Vane gear

Gareth

Hi Dave,

Well this will be interesting? I thought model boating was so simple, but maybe not, I learned a while ago never to ask yourself why you do the hobby? It only gets in the way of building the next project 😀

I had to Google Arduino, still non the wiser, is it some sort of Yoga??

Happy Christmas

Ray

Edited By Ray Wood 2 on 25/12/2019 07:35:33

Thanks Gareth,

Sounds very clever, well above my aspirations 😀 simple is good in my book.

All the best

Ray

Dave,

My plan was slightly different but also based on a staged approach

Step 1 was was to restore the yacht, which was essentially a wreck, and make it a dual control, radio or vane steered yacht. This was done and it was initially sailed under radio to get the basics sorted out and the mast in the right place. Then it was sailed as a vane boat, including a weekend at Fleetwood in their Vintage Marblehead competition. After about 20 trips each way down the pond over the weekend it was reasonably sorted and there is a picture of it below.

The next step is to fit the Arduino with a data logger and sensors to monitor what the boat is doing when being vane steered. Planned sensors are position by GPS, compass heading, rudder position to see what the vane gear is commanding and wind direction.

The third step is then to remove the vane gear and program the Arduino to try and emulate the vane gear. Its important to realise that the vane gear only attempts to maintain a constant heading relative to the wind direction and its a big assumption that the wind is blowing in the same direction all along the course you want to sail. One of the big advantages of the lake at Fleetwood is the wind is reasonably true. If you are trying to make adjustments to a vane steering system and the wind is being deflected by trees or other obstructions it gets very confusing and frustrating.

The next step is to develop the step three control system so it could be applied when tacking upwind.

The fifth step is to go one step beyond what a vane gear can do and that is to steer a course on a constant heading, in all directions relative to the wind.

Finally the aim is to get the control system to be able to sail a programmed course which would mean the Arduino would have to take control of the sailwinch as well as the rudder.

Hopefully I will make some progress on the project this year but I have got lots of other things to do so maybe it will stay on the shelf for a while longer.

Gareth

Tim – don't hold your breath, I may be a while getting started.

Gareth

Ah ha Ray!

Nice idea but if it were me I would race it with another yacht.

In fact I could see it as an interesting training tool. Bit like a buddy box.

Tim R

Hi Dave

I don't think vane gears are self tacking in the sense that they tack themselves. It is more like a dual setting where the vane flips to an identical setting but on the opposite tack. What initiates the tack is the skipper pushing the bow through the wind with a pole. The people sailing the big boats must be very fit to keep up with them on the pond.
Me? I would need an electric scooter for sure.

Probably it is called Radio Control that can make it tack a number of times before reaching the opposite bank

The vane looks after wind-shifts by itself so if the winds heads ie comes closer to the bow, the boat would bear away to keep the angle the same. Choosing when to tack is the big advantage of RC because if the wind heads you should tack and that way make much quicker progress to windward.

Tim R