Vane Steering for Model Yachts

[Dave Cooper 6Participant @davecooper6]

Thanks for that Tim – I thought I was going a bit mad for a moment !

So, it's not so much "Self-Tacking" as "Self-Correcting" on the same tack…(much as you'd expect an 'autopilot' system to do) ?

I'm left wondering, therefore, what would it do if there was a really massive wind shift – say, 120 degrees ? Would it flip the vane across the transom and then try to take up a new tack, or, would the vane gear prevent this ?

Still learning !!!

Regards,

Dave

[Gareth JonesParticipant @garethjones79649]

Dave,

Tim is quite correct in his description of a self tacking vane, The vane does not initiate the tacking manoeuver, that has to be done by the skipper or his mate on the opposite bank poling the bow of the yacht across until the jib sail fills and the vane then automatically flips over to the position appropriate for sailing on the opposite tack. The advantage that the self tacking vane gives is that the yacht does not need to be stopped to make a manual adjustment to the vane's position.

When the vane is broken it is held over on one or other side of its travel, partly by its weight assisted by the heeling of the boat, partly by the aerodynamic forces on the feather from the wind and also by a light overcentre spring. The spring prevents the vane from flipping over on to the opposite tack in the event of a gusty wind or choppy water. However the vane gear has to be set up carefully to ensure that when the boat is poled on to the opposite tack, the spring is not too tight and prevents the vane flipping over to the opposite side.

Its not unknown for boats to change tack inadvertantly and this phenomenon is exploited in guying when an overcentre spring is set up 'off centre' so the vane is held more positively at one side of its travel than the other. The boat is released on the tack where the vane is only lightly held in position. In the event of a change of wind speed or direction the vane flips over on to the opposite side and turns the boat. Because the vane is more positively held in this new position the boat should stay on this new heading. Its a useful tactic when you are near the finish line and don't want the yacht to go all the way over to the other side of the pond. However there is an element of chance in what will happen and setting just the right spring tension and offset requires great skill and experience.

I think every vane sailor is still learning, no matter how long they have been doing it. Its a big help in understanding vane sailing if you can find somewhere its practiced and watch and ask questions. Its a very sociable form of model yacht racing, much less aggressive than radio sailing. Unfortunately there are not that many sites where it is now possible as all round access to the pond or lake is required. The main centres nowadays are probably Fleetwood, Birkenhead, Bournville, Gosport, Hampton Court and possibly the Round Pond and Clapham in London – if I have missed anywhere out I apologize.

Gareth

[Gareth JonesParticipant @garethjones79649]

Ray,

I have to be careful what I say about Arduinos as I have been known to upset people in the past. The attraction in using them or similar devices to achieve some sort of automatic control is, to me at least, the challenge of making the system work and particularly making it work effectively. Its just another aspect of building the model like getting the scale, accuracy or painting done to the best of your ability. The fact that the control system might take away some of the skill or effort needed to sail the model is a secondary consideration. In practice the knowledge and understanding a person needs to acquire and apply to making an automatic system work would probably make that person a better operator of a purely 'manual' system.

Gareth

Edited By Gareth Jones on 27/12/2019 09:52:15

[Malcolm FraryParticipant @malcolmfrary95515]

Posted by Gareth Jones on 27/12/2019 09:51:23:

Ray,

I have to be careful what I say about Arduinos as I have been known to upset people in the past. The attraction in using them or similar devices to achieve some sort of automatic control is, to me at least, the challenge of making the system work and particularly making it work effectively. Its just another aspect of building the model like getting the scale, accuracy or painting done to the best of your ability. The fact that the control system might take away some of the skill or effort needed to sail the model is a secondary consideration. In practice the knowledge and understanding a person needs to acquire and apply to making an automatic system work would probably make that person a better operator of a purely 'manual' system.

Gareth

Edited By Gareth Jones on 27/12/2019 09:52:15

I think that before you can effectively use any form of on board computer to enhance control of a model yacht, you need a deep understanding of how a model yacht behaves and reacts to its environment.

If you want a boat to fulfill and objective ("go from here, get to there&quot an on board computer with position and direction sensing and enough power should make it happen. Doing it with a yacht that has to cope with varying wind conditions without getting into an unrecoverable situation is less easy. On "my" lake, due to varying wind strength and direction caused by the nearby trees, I have watched one of mine sail a straight course and tack 3 times in about 10 yards without changing direction. Entertaining, but it illustrated the point that that corner of the lake is not a good spot to learn to sail a windy boat.

The challenge of getting an automated system to work must have its interests, but before it has any chance of working, there is a strong need to know how to do it manually.

[Ray Wood 3Participant @raywood3]

Hi Gareth,

Yes being a self confessed ludite, I dislike computers, having said that I have been using them to earn a living for 30 years, so the ends justify the means, not knowing how they work has never been an issue, but old technologies like sailing boats, steam engines and aeroplanes (pre fly by wire) I have an understanding of how they work, I think I understand the challenge and will watch this thread with interest 😀

Regards Ray

[Dave Cooper 6Participant @davecooper6]

Thanks for that Gareth – the 'fog' is now beginning to clear ! Yes, I'd like to see some vane sailing /racing somewhere. I'm sure that will fill-in any blank spaces I still have…

Ray : Coming back to Arduino, I think you can treat it a bit like a "black box" eg. the inner workings of your TV set is probably beyond most peoples' understanding….however, you don't need this knowledge to enjoy a good programme – just how to work the remote ! Ditto your Tx an Rx on a 2.4 GHz radio….

Because Arduino is 'programmable', you can make it do lots of different things – move a servo or, stepper motor, blink an LED, sound a horn etc, etc. So, there is a learning curve involved but, there is much pre-written stuff you can employ which just needs 'tailoring' to do the particular job you have in mind.

Cheers for now – I'm off to look at yacht designs, plans, kits for a bit of light relief… !

Dave

[Gareth JonesParticipant @garethjones79649]

Watch out Ray, I think Luddite was the word that got me into trouble last time.

Gareth

[Ray Wood 3Participant @raywood3]

Thanks Gareth,

At least you knew how to spell it correctly 😀

Regards Ray

[Dave Cooper 6Participant @davecooper6]

Hi all – hope you had a good Christmas.

Just looking through Sarik's kits and plans and came across the yacht "Ardent". It's about 900mm loa and 260mm beam with a low(ish) cabin and conventional Bermudan rig.

Just wondering about this as a basis for my experiments ? Couldn't find a kit, so, the plan would be the starting point.

It'll fit in my car although the mast may have to be 1400-1500mm high ? If so, I may need to be able to de-rig it for transport…

I would fit an electric motor /folding prop, plus, vane gear and radio for the various experiments.

Thoughts ?

Dave

[Dave Cooper 6Participant @davecooper6]

Yacht "Ardent" from Sarik plans – possible contender for the radio /vane experiments. 900mm loa, 260mm beam.

[Ray Wood 3Participant @raywood3]

Hello Dave,

That would be an excellent choice, put an electric outboard on the back for your auxiliary get you home motor.

Regards Ray

[Malcolm FraryParticipant @malcolmfrary95515]

The vane might need to live on a bracket over the stern. They don't really play well with a backstay, both wanting to occupy the same space.

[Dave Cooper 6Participant @davecooper6]

Hi Malcolm

Yes, I was wondering about the backstay too. I'll need some space for the epicyclic gear so, was wondering about designing in a stern extension /overhang to house it all ?

Really need to see the plans in detail before deciding anything. I think the critical dimension will be the 'sun and planet' outer ring. I could make one (brass) to fit but it would mean buying a dividing head….also, not sure if nylon gears will take the rudder loads – maybe a 'buggie' diff' or 'heli' mast-head gears in good quality nylon would suffice…

Happy new year,

Dave

[Ray Wood 3Participant @raywood3]

Hi Dave,

As your not racing the backstay is not really required, move the shroud chain plates back 1 1/2" to support the mast. Job done 😀

Regards Ray

[Dave Cooper 6Participant @davecooper6]

Thanks Ray – that sounds like a nice easy solution !

Happy new year,

Dave

[Ray Wood 3Participant @raywood3]

Hi Dave,

I just recalled Eddie Lancaster built Ardent in January 2018' thread was "Building Ardent" Eddie is a steamer converted over to sailing and builds exceptionally good models 😀

Ardent was one of his earliest posts and shows the rc installation.

Regards Ray

[redpmgParticipant @redpmg]

Dave – Vic Smeed produced quite a few vane steered yachts . I am building 2 small Elvers to use with my grandson from the revived Madel Maker in the 80's. The one I am currently looking at appeared in Model Maker December 54 . Called Water Baby it was for the proposed MM class – and is round bilged. Very nice looking little yacht.. In Jan 55 a plan was published for Sea Urchin – hard chined – simple construction for the same class . In Feb 55 an article was published with additional detail for the sails & rigging detail for both. I have a copy of all 3 articles if you are interested. Although they are fairly small scale both designs could easily be scaled up . PM me if you would like a copy

[Dave Cooper 6Participant @davecooper6]

Hi Ray – thanks again. I'll see if I can find the Ardent build thread, it could be very useful for the r/c part of the installation.

Hello redpmg (hope I got that right…). Funnily enough, I was given an old MM Plans Handbook from just that era (recovered from a skip !) and those designs are in there. Yes, always interested in articles like that…PM sent with thanks.

Happy new year,

Dave

[Gareth JonesParticipant @garethjones79649]

Dave,

Its quite common to mount the vane gear on a bracket overhanging the transom on 36R class yachts as shown in the picture below. The 36R is the only formally recognised class where this is allowed. For Marbleheads, 10 Raters and A class boats the axis of the vane gear must be inboard on the hull. However since you are making an experimental installation of your own design and it is not going to be measured or registered you can of course do as you please.

It is also quite common on vane steered yachts for the lower section of the back stay to be split into two separate lines as shown in the photo, so they stay clear of the vane gear in all its possible positions.

Gareth

[Dave Cooper 6Participant @davecooper6]

Thanks for that Gareth,

I think my set-up will probably need to be inboard, or, perhaps with a small overhang…the split back-stay is a useful idea though.

At the moment, it's looking like a 3-servo system :

Sail Winch, conventional RC steering and epicyclic band clutch (may need an extra one for the planet carrier). The vane pivot will sit above the 'sun' gear….the epicyclic train will reverse rudder direction and gear down the vane (something like 2:1 I should think).

Next thing will be to get a test rig working on the bench. The outer ring gear is proving difficult to source. May end up having to make one ! Currently looking at Buggy diff's and Heli' parts to see if there's anything useable there.

Happy new year,

Dave

[Dave Cooper 6Participant @davecooper6]

Hi All – latest on the yacht project :

I'm told that a cordless drill /screwdriver works on a 'planetary' gear principle. Having a defunct one of these in my garage (battery won't hold it's charge), I'm planning to strip it down and see if the gearbox may be suitable.

The motor is also 9.6v – possibly coreless, so, this may be of some use too….

I will weigh everything as I go and then try to build a test rig with a 'dummy' vane to see what the possibilities are.

Hopefully, photos to follow,

Dave

[Author]

Posts