Interesting.
That's not an anchor. It's a piece of scrap metal!
We never anchor without a snubber. We only anchor.
A 30kt gust might wake me up but I probably wouldn't get out of bed.
Mine is nearly as bad as that and less than 2 years old! Anchoring full time takes it toll on terrible galvanising.
Similar winds my 12m of 10mm nylon will stretch maybe 20, maybe 30mm. Need to watch carefully to notice it. So hardly ever use it, chain grab welded to the deck to take the load off the windlass. 10T steel 33' steel boat. Live on the hook. Every boat is different...
🌬Oh! It's a pissing contest
but on the actual figures, I tend to agree.Agrred, his shoot from the hip, take no prisoners style quickly gets tedious.
).The thread has drifted - it matters not what you or we think - the Spade anchor bent under the conditions they described. Whether it was 20 knots or 40 knots - the shank bent, and weld failed.
In order to bend the shank and tear a weld there must have been significant impacts - so forget what you believe and take the facts at face value.
My interpretation is that the fluke held (its an excellent fluke design, (copied to build the Rocna, Vulcan and Ultra, maybe others) tenaciously. There were repetitive snatch loads but the snubber (and scope) was inadequate - and the snatch loads were impacted on the shank - which failed. The shank should not have failed, ever (or almost ever). My guess is the snatch loads were of the order of 450kg and up, enough to bend the shank one way, then the other repetitively.
At what windspeed this occurred - obviously not exceptional - this might be indicative of the need for a good snubber. It maybe they could not deploy more rode (and improve the scope) no room is the common reason. Its easy to be wise after the event - especially sitting at your keyboard - we don't know what the constraints were.
Whether you think a snubber is needed is a personal decision - the data is all available. If you use a Kobra - I would take note. If you sail a catamaran I would suggest that the supplied bridles are not adequate. If you have a plastic fantastic monohull from any of the big builders - consider a long snubber that will give elasticity (even if you are sceptical - give it a try). If you have a heavy displacement yacht with a large chain link - I have no experience - but the inertia of the hull suggests less dangers (not no dangers) from snatch loads. Never say never. Maybe try it - and then report back.
If you are in Sydney, not many of you. I have spare (30m) snubbers and bridles I can lend out for a period for anyone to try - you can then make your own decisions. I'd make the offer to anyone, anywhere - but its expensive sending rope round the world to prove a point (that does not need proven
Jonathan
I broke an aluminium Spade anchor in 2004. We were anchored on a rocky bottom. A 5.5 tonne boat in relatively benign conditions. The anchor got stuck under a rock. With a manual windlass we loaded up the anchor to see if it would break free. It didn't. We drove around the anchor with the engine to see if we could clear the stuck anchor. We did eventually. When the anchor came up, the shaft was split.The thread has drifted - it matters not what you or we think - the Spade anchor bent under the conditions they described. Whether it was 20 knots or 40 knots - the shank bent, and weld failed.
In order to bend the shank and tear a weld there must have been significant impacts - so forget what you believe and take the facts at face value.
My interpretation is that the fluke held (its an excellent fluke design, (copied to build the Rocna, Vulcan and Ultra, maybe others) tenaciously. There were repetitive snatch loads but the snubber (and scope) was inadequate - and the snatch loads were impacted on the shank - which failed. The shank should not have failed, ever (or almost ever). My guess is the snatch loads were of the order of 450kg and up, enough to bend the shank one way, then the other repetitively.
At what windspeed this occurred - obviously not exceptional - this might be indicative of the need for a good snubber. It maybe they could not deploy more rode (and improve the scope) no room is the common reason. Its easy to be wise after the event - especially sitting at your keyboard - we don't know what the constraints were.
Whether you think a snubber is needed is a personal decision - the data is all available. If you use a Kobra - I would take note. If you sail a catamaran I would suggest that the supplied bridles are not adequate. If you have a plastic fantastic monohull from any of the big builders - consider a long snubber that will give elasticity (even if you are sceptical - give it a try). If you have a heavy displacement yacht with a large chain link - I have no experience - but the inertia of the hull suggests less dangers (not no dangers) from snatch loads. Never say never. Maybe try it - and then report back.
If you are in Sydney, not many of you. I have spare (30m) snubbers and bridles I can lend out for a period for anyone to try - you can then make your own decisions. I'd make the offer to anyone, anywhere - but its expensive sending rope round the world to prove a point (that does not need proven
Jonathan
). I assume the recommended hard wiring is to displays and to Blue Tooth. My build includes a B2B charger - which I have not yet trialed. I have been charging with solar.
It's an anchor. Where do you want be to put it? In my pocketOf course its rusty, if you leave it in the seabed.
Jonathan
If it helps, we have 385Ah of lithium house bank in two batteries at 24v. Equivalent to 770Ah at 12v. 3000w low frequency inverter. 920w of solar. 2000w induction hob. The large capacity battery gives us the ability to deal with cloudy conditions for few days and still cook on the induction hobIn a recent teaser MG have said that only Lithium batteries with the cells having individual BMS should be used in the marine environment, this is consistent with the advice given on Lithium threads here. However it is also said that Blue Tooth is inadequate (the last word is mine). They say that the BMS should be hard wired (the implication is that some batteries offer Blue Tooth to communicate (am I showing my total ignorance?
However they go further and say that there should be an alarm, sufficient that it cannot be ignored, to indicate that an issue is developing and should be attended to NOW rather than have a battery shut down.
Finally they say that in the absence of these measures it should be anticipated that, marine, insurance companies will become twitchy, or attentive.
The new information for me was that communication with the BMS was via Blue Tooth not wired. I had assumed that Blue Tooth enabled batteries had hard wiring to displays and that the Blue Tooth offered another way to access the displays. This may have been my misunderstanding. The idea it was possible to anticipate and shut down and provide audio/visual warning of an impending shut down was the first time I had seen the idea aired. The article did not indicate how this warning could be achieved.
I have taken on board the absence of any ability to monitor individual cells in my 'drop in' battery. I am not going to throw it out - I'm too mean. When I am happy with my build and want to formalise and instal it - I'll buy 'off the shelf' batteries with a programmable BMS - or I'll build my own. Not entirely sure what to do with the 'Drop In' battery. Maybe by then Lithium will be old hat and we will all be clamouring for Sodium.
I have learnt from my build. 300 watts of solar is quite powerful, but maybe 500 watts would be better. A 200amp Lithium battery is too small, the 300 watt solar is often going to waste. But get 2 days of poor weather, as we have just had in Sydney, and the battery is too small. There must be a balance between total battery amps and solar watts - but I don't know what the balance is, yet - for an all electric build, cooking, water heating, desalinator, instruments.....Our inverter is far too small at 1500 watts. Again not sure what is needed but currently I'm thinking 3,000 watts.
Its a learning process and I'm pleased to be learning in a home environment - it would be difficult on a yacht - all credit to those living aboard with the accomodation dominated by a spaghetti of wires.
Jonathan
I think you made the right decision switching materials.
