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[mike javelin]

We sail Micro Magic yachts at Southwold model lake.

The lake is a little under 1mt deep and every time we sail we have to put our bouys out to race round.

We've tried using a long line on the buoy, weighed down with shot so we can retrieve the buoys but in practice this is a pain.
People trip over the line, the line stops us getting the buoy out far enough and frankly its a pain to neatly coil it up when its wet and weedy at the end of the day, resulting in a real mess the next time we need them.

So what we want is a powered RC boat to sail out, so we can drop the buoys and importantly at the end of the day we can go out and retrieve them.

The buoys are weighted down with fishing leads with barbs on to stop them dragging, so the boat would either have to be very powerful to drag the buoys in or would have to have some way of lifting them up.

Anyway I thought this would be the best place to ask but be kind as I know zip about power boats.

[djrobbo]

Your one big problem is the fact you say you use barbed weights . i assume these are beachcaster weights , if thats the case i think they would firmly anchor most radio power boats that tried to retrieve them , have you thought about a small dingy ?

              some of the other lads on here may know better .

                        regards.bob.

[norry]

...Hi Mike...

You could use self release grip leads which would make it easier for a boat to retreive them...
You set the grippers then hold them back in place with an elastic band...when it is pulled hard enough the elastic band slides back & releases the grippers, It is then just like a normal fishing weight...

Is using Chest Waders out of the question or what about a small dinghy...

These are the methods that are used at most if not all of the clubs that i have visited...

...Best Regards...Norry...

[mike javelin]

We don't have a dinghy close and to be honest it wouldn't be as much fun anyway.  :)
A couple of our MM sailors are also in the RNLI and they come down with their drysuits/waders but again it's a fag and it would be much better to have an RC solution.

And I'm getting the feeling this is turning into a challenge!

If the weights are a problem we could change them but we don't want them to drag and we sail in most conditions.

In fact a month ago we were racing (with very small sails) and the local club anemometer read an average of 34knts and a peak gust of 41 !!

Ok this is unusual but we often race in a force five and so dragging buoys could be a problem.

We did attach our first sets of buoys to large lumps of concrete but during the week some kind soul removed them as it's a public pond and it is Southwold after all  ::)
 

[toesupwa]

The local club here in California anchor their buoys with 5lb weights....

A Springer will push the buoys around without a problem. Perhaps some type of deployment / retrieval system could be added to a Springer?...

[mike javelin]

Sorry but what on earth is a Springer?

An ex guest on an American talkshow perhaps?

Sorry like I said earlier my powerboat knowledge is zero.

[HS93 (RIP)]

Read


http://www.modelboatmayhem.co.uk/forum/index.php?topic=3471.0

Peter

[mike javelin]

Hmmm, OK so I know what a Springer is now but I can't see how it helps me yet.

I just knocked up a drawing in photoshop of the sort of thing that might work.

Three channel, drive, steer and a winch.

Although what motor, and power system I would use I've not got the foggiest and I guess I could get a yacht sail winch.

[tigertiger]

Here is an idea that springs to mind.

You build small motorised buoys.
It may seem like a bit of a pain as you  will need to build more than one, but I believe it will serve your purpose well.


If you use soft drinks bottles for catamaran hulls it will keep down the work and costs.
Pyramid weights hold the bottom well, and don't catch in weeds.
You can make your own or buy from a sea angling shop.
They also lift very easy, two kg as in the picture would probably be overkill even on a very windy day.

Drum winch can be made from a modified servo. I have seen a thread on here as how this is done. Somebody else on mayhem would be a better source of advice on mods I am sure.

Using a schottle drive will keep things simple, but is expensive.
If you do a search on the Mayhem sight for 'rescue boats, I think there is a cheaper method of sorting out the steering using pop bottles.

Alternatively, you could build the buoy, with winch, but without propulsion, and push them out using any other boat, including a sail boat or a cheap RTR

Like I say, just an idea. But I think multiple mobile buoys is the best way froward.

[tigertiger]

http://www.modelboatmayhem.co.uk/forum/index.php?topic=6367.0

Check this thread, reply #9 for a bottle boat idea.

Remember that any motorised buoy, or recovery boat for them, does not need to perform that well.

Another idea. Some of the cheapo motorboats on ebay have two externally mounted motors and have proportional steering. (i.e. run one motor or the other to steer. both to go forward) these could be ripped out and attached to the pop bottles.

[MikeK]

Hi Mike
In the early days of Three River MYC before they were allowed permanent buoys, we made a raft between two pop bottles, with a bridle that hooked on to the backstay of a Marbelhead yacht. The buoys were the usual painted canisters/bottles secured by small chain, down to weights and the line running from the weights along the lake bed to cheap fishing reels on shore. To lay them, they were piled on the raft and towed into position with someone else paying out the line, a sharp tug and a most realistic noise of an anchor being dropped and hey presto ! At the end of the day we just reeled them in. I don't recall having much problem with snagging (The lake is an ex gravel pit with the usual weed infestation) and the fishing line was not buoyant. Hope this may give you thoughts

Mike

[malcolmfrary]

Getting a buoy into position is not really a problem, it just needs a big enough boat to get it out there and dump it.  Even this does not need an extra channel, just a long line to jerk the buoy off the boat when in position.
The devil is getting it back.  The simplest way is probably to tow a line round the buoy and use muscle power to bring it back.  With the wind conditions described, a big strong boat is wanted, probably an enlarged springer, or a more conventional tug hull.

[sheerline]

If it's really only retrieval thats the problem, couldn't you simply use any small motorised craft to carry a non floatable line from a bobbin on the bank out to the bouy, drive it around the buoy a couple of times and return the boat with its end of the line to the bank? This way, all you need do is pull on one of the lines so the loop  tightens around the bouys weighted anchor line and gripping both lines, haul it in. If your'e worried about a prop fouling the line, you could always haul the boat back with it or go after a water jet model as this wouldn't snag anything.

[MikeK]

Just taken a closer look at Tigertiger's drawing of the bottle boat and that is more or less identical to the one we towed, except it had a clean flat surface

Mike

[mike javelin]

Many thanks,

Some great ideas.
My worry about the self propelled buoys is that you either have to have a radio and Cristal for each buoy and non of the sailors could use them as you can't turn off the reciever.
Other than that I like the sound of them.

Running a line out from the bank sounds pretty simple and I could probably do this with the yacht as well.

However I still like the challenge of producing a purpose build craft, you never no Trinity House might like it and build a full size one