Self adjusting --- retractable anchor buoy

[bobs]

Could someone help me out with a question I have on a self adjusting anchorbuoy please ?

Self-Adjusting Anchor Buoy

I was wondering , how is the lower/bottom part of this buoy constructed ?
Is that an open area , meaning ....can seawater enter free ( through the trip line exit) or is there some kind of siphon integrated ?

Thanks
Regards

[senormechanico]

Internal spring loaded roller?

[bobs]

Hello ,

yes of course spring inside it is. But I my question is , whether the lower part of this buoy is filled with seawater when it's deployed.
Because of the weight and pull (anchor and tripline) it's submerged halfway , that means the buoy - if the passage of the line comming out of the buoy is open - water will be getting in no ?
So everytime you retrieve the buoy you will have to drain it .
Or do I see that wrong ?

Thanks
regards

[HopCar]

Here is where they sell parts for it Parts for self adjusting anchor buoy

If that doesn't answer the question, you could just ask them.

[bobs]

Hey Hopcar ,

by providing the links you gave me the answer to my question. The lower part of that buoy is indeed filled with seawater up to a certain level . Compairing all the pictures , also those on the official Switec site , it seems like the spring is (partially ) submerged . Must be a very high grade S/S. If not , rusty water will be dripping continuously on the deck whilst the buoy is in the craddle.

Thanks alot

Ps :
Although I've seen this buoy on some boats , not many seem to have it by the looks of the responses on the board.

[noelex 77]

It does not answer your question, but you can make your own slightly less elegant version by attaching a small block (or low friction loop) to the underside of a suitable buoy. The line from the anchor goes around the block and is attached to a weight. The weight keeps the line reasonably taught and the line length automatically adjusts for a rise or fall of the water level.

Personally, I am always concerned about our boat (or another) catching these marker buoys. If a boat drifts over the anchor buoy it can become trapped between say the rudder and hull, or around the stern ladder. If this occurs, force is applied to the anchor trip line at virtually 1:1 and even a well set anchor will break out. I have seen this happen on several occasions.

My solution is to have a weak link (I use a cable tie) just below the waterline. If the buoy becomes trapped (or someone tries to use it as a mooring) the weak link will snap before the anchor is dislodged. If the trip line needs to be used in anger, a stronger line can be attached from the dinghy to a loop lower than the weak link. I use cheap (actually usually found on the beach, so free) fishing floats, so the occasional loss is not a concern.

For the length of line, I use a simple low tech approach of few different floats for different depths. The length does not have to be perfect so a few options covers most anchoring depths. The line can always be shortened with say an alpine butterfly loop. This low tech (and inexpensive) approach works for areas with reasonable tidal range. For those cruising grounds with a high tidal variation, the weight idea is needed if you want the buoy to reasonably accurately reflect the anchor position, but it is more difficult to incorporate a weak link.

If you have an anchor that sets quickly, snagging the anchor resulting in a trip line being needed is quite rare. Wrapping the chain around a rock or coral head is slightly more common, but a trip line is of limited help here.

An anchor buoy does mean generally that your boat takes up more room in the anchorage. It is therefore a little inconsiderate to use one in a crowded anchorage. It is also a hazard for any boat that might be entering the anchorage at night.

In variable wind it is worth keeping track of where your anchor is located, but this can be done with GPS. If you want to pinpoint the location a hand bearing compass and laser rangefinder can then get very close.

[noelex 77]

I would recommend a simple low tech solution, but a rival commercial product that is also self adjusting is the "Anchorroll".

I have seen the SWI-TEC Anchor Buoy on a few boats with no signs of rust. I have not personally seen the the Anchorroll in use.

https://company.metstrade.com/Image/...ad?docid=28183

[bobs]

Thanks for chipping in Noelex , I'm aware of the pro's and con's of deploying an anchorbuoy.
Up to now I only used my buoy (non retractable mind you) in non-crowded places , not just to warn other boaters , but also in case the anchor gets stuck or the chain breaks.
It's a (DIY) 316 L SS Rocna around 30kg and I would cry my eyes out if I would lose this anchor.
Last year my chain gave away during a gale , I was lucky to be able to retrieve my anchor and decided to play it safe in the future.
The reason for me inquiring about the science behind a self adjusting buoy is because I'm in the mids of making one myself.
Many thanks for the link of the anchorroll . Sofar I just came up with the Switec and the automated anchorbuoy.
The thing is , I would like a retractable buoy with automatic nocturnal light , and of course a small solar panel to feed the internal battery.
The automated anchorbuoy does have these features , but the adjusting line is electrically driven and looks like a fishing line instead of a trip line.
The Automated AnchorBuoy
The Switec doesn't have a light ( not build that is ) and no solarpanel.

With my concept I would like to combine these two worlds.
And there's also the fun in making it yourself is it not ?

Regards

[jackdale]

Why use something so complicated?

Either use line impregnated with metal so that it sinks or attach weights to your anchor buoy.



KISS

[poiu]

I have a bit of a dilemma with this. If you use an anchor buoy in a busy anchorage you will sterilise a very large area of real estate as other boaters will not want to drift back and sit near your buoy, yet it is often ok if they do. All the more a problem if you use a decent scope of 5:1. There is no doubt that in the busiest spots some people not care less and will drift over the anchor buoy anyway. They may cut it away if tangled.

On the other hand some boaters are happy to use 3:1 or less and expect you to do so too. They will drop on your anchor if you are not looking and it's a pain to guard your space all the time.

Sometimes I shorten the chain, then lengthen at bed time. Busy anchorages can be stressful.

[noelex 77]

Sounds like a great project. Make sure you post instructions on CF.

I am more in line with Jack's KISS approach myself, but commercially these things are very expensive so I am sure there will be lots of interest.

One caution, is to make any lights etc tough. In changeable wind the buoy invariably ends up going under the boat, at some stage. All my buoys have nice blue antifouling scrapes on them.

For lighting these flashing LED fishing markers are very tough. They are only a few dollars and have a photo sensor to turn off during the day. They are not solar, but a flashing LED uses little power so batteries last a long time. They are available in various battery sizes.

Here are a couple of mine. I use them on stern lines when Med moored. Sometimes you need to have reasonably long stern lines leading to rocks or a tree. There is a risk that a tender or small fishing boat could pass between your stern and rocks so the lights (and a fender during the day) provide a warning. I am sure they would also work well on an anchor float.

[poiu]

Originally Posted by noelex 77

Sounds like a great project. Make sure you post instructions on CF.

I am more in line with Jack's KISS approach myself, but commercially these things are very expensive so I am sure there will be lots of interest.

One caution, is to make any lights etc tough. In changeable wind the buoy invariably ends up going under the boat, at some stage. All my buoys have nice blue antifouling scrapes on them.

For lighting these flashing LED fishing markers are very tough. They are only a few dollars and have a photo sensor to turn off during the day. They are not solar, but a flashing LED uses little power so batteries last a long time. They are available in various battery sizes.

Here are a couple of mine. I use them on stern lines when Med moored. Sometimes you need to have reasonably long stern lines leading to rocks or a tree. There is a risk that a tender or small fishing boat could pass between your stern and rocks so the lights (and a fender during the day) provide a warning. I am sure they would also work well on an anchor float.

How do you fix the fenders and lights along the stern line so they are easy to attach and remove, yet stay in position?

[noelex 77]

Originally Posted by poiu

How do you fix the fenders and lights along the stern line so they are easy to attach and remove, yet stay in position?

That's easy. My wife (Seaworthy Lass) is a bit of a knot Nazi. So I usually tie a granny knot and she goes and fixes them, muttering under her breath

[HappyMdRSailor]

Originally Posted by noelex 77

That's easy. My wife (Seaworthy Lass) is a bit of a knot Nazi. So I usually tie a granny knot and she goes and fixes them, muttering under her breath

HA!

Apparently just above the audible threshold, but below the discernable...

Knotzi.... If that didn't have such negative connotations, that would be a great boat name... Especially for a racing boat...

[poiu]

Originally Posted by noelex 77

That's easy. My wife (Seaworthy Lass) is a bit of a knot Nazi. So I usually tie a granny knot and she goes and fixes them, muttering under her breath

It might be easy for some. No Nazis here to help. I struggled with this. My rolling hitches slipped with the jangling of the fender. I need to broaden my knot repertoire. I will try a constrictor knot next. Hope it doesn't become a pain to undo.