masthead floats

Started by Michael Rogers, 10 Jul 2015, 23:12

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Michael Rogers

Yes, well, I got my Crewsaver 9 litre thingy from Sailboats. I feel a bit like either Smith or Jones (remember them?) who didn't think much of flatpack furniture - 'I got it home in this box, and it said "self assembly" on the side. I put it on the floor, and watched it for half an hour, and it didn't do nothing. In the end I had to put it together myself'.

Now where did I get the idea that these mast floats were self-inflating, like a life jacket? Not this one anyway, just a tube to blow into with a (apparently fairly efficient) valve on the end. I sense the more worldly-wise of you falling about with laughter - 'what did you think you would get for that sort of money?' Well, frankly I think nearly £60 for a plain (admittedly fairly tough-looking) air sac, which my boat has to wear fully inflated (by me), is a rip-off.

I had a look to see if I could find a self-inflating add-on gadget with which to modify my brave new windbag, but no progress. Any ideas? Meanwhile, please do have a good old guffaw at my expense. And next time I fancy a jaunt in a F6, I might just grit my teeth, apologise to Cavatina, huff and puff, and send it aloft. Huh.

Michael

maxr


Graham W

Michael,

I did wonder when you said that if you looked around on t'interweb, you could get the Secumar much cheaper than at Tridentuk.com.  Max's chandlery is about 10% cheaper for the Secumar, which made me suspect that it is one of Marine Megastore's very ugly sisters.  It isn't - in true passing-off style, the Marine Megastore version has an extra hyphen in its name, as in http://www.marine-chandlery.com/default.asp?Menu=1164.

Anyway, can you send the Crewsaver back?  Otherwise, you can join me on eBay, selling off mistaken, surplus and unwanted purchases.  I've already raised a (very) small fortune and can now nearly get into my shed.
Gunter-rigged GRP BR20 No.59 'Turaco III'

michaeln

In following this thread I noticed the following warning on the Crewsaver Website re the deployment of their masthead float. "N.B. Not suitable for boats without anchoring" ?????
Michael

BR20 #32 "Aoife"

Peter Taylor

Michael R

I'm sorry you were disappointed by the Crewsaver masthead float.  In it's defence I'd say the price is in line with what you pay for buoyancy bags (which I admit always seem expensive to me!).  No it does not self inflate but it is reasonably neat at the top of the mast if you really must have something up there - I attach a photo of it on my Seafly (which I've posted here before).  The bag is remarkably strong, the one I have has been on the top of my Seafly mast for several years continuously exposed to the elements and it still does not leak.

I think the reference to "anchoring" is meant to imply that you must actually anchor it to the mast rather than to hoist it on a halyard, i.e. you need a way to fasten it to the mast. I've only tested the bag once "in anger" and the Seafly did not turtle - which they are otherwise prone to do.  For me the sacrifice in looks and aerodynamics is worthwhile if it stops the mast ending up stuck in the mud at the bottom of the River Itchen!

Peter
Peter Taylor
BayCruiser 20 "Seatern" (009)
http://www.seatern.uk

David Hudson

David H.
BRe No. 35
"Amy Eleanor" (and the dangerous brothers)

Matthew P

Quote from: David Hudson on 12 Jul 2015, 21:02
Or this....
http://www.henshaw.co.uk/products/337-3-x-11m-self-righting-bag
Excellent David!  I notice this is recommended for a boat of 10M, alarmingly not much bigger than a 6M Bayraider. OK, I know boat volume goes up with the cube of the length etc, but still....

Speaking as a "person of some experience" and not entirely tongue in cheek, I now stow all my "Ship" stuff (bits of string, various sticks and hefty repair kit) in my port locker and personal stuff (spare clothing, food, 1st aid kit, more food and more spare clothes) in my Starboard locker.   This not only makes finding crucial pieces of string and food easier but also provides some minor but perhaps useful additional buoyancy on the starboard side because my personal stuff is mostly in roll-top, hopefully water-tight, bags of reasonable volume.   So the additional buoyancy is opposite to the self-flooding, self-righting, compartment on the port side.  And my personal stuff will not sink in an inversion.  The ship-stuff in the port locker (much of it not floaty) has to rely on the locker latch to stay aboard.  All this is of course somewhat pessimistic but once wetted, twice shy. 

To reduce the chances of capsize and as many people are now bored of me explaining, I  have now more than doubled the speed of flooding the ballast tank by reversing the direction of one of the self-balers and removed the flap so when deployed it acts a forward facing scoop with a satisfyingly forceful water fountain.  As the self-balers only seem to self-bail in conditions when I want to fill the ballast tank, not empty it,  the loss of one bailer is not a problem. I have also fitted a bigger drain bung with double the cross sectional area.  Both these mods proved useful in Falmouth when on two occasions I chickened-out and filled the ballast tank.  I better admit this was when running before an increasing breeze on open water and not when tacking our way up the river, when Gladys was un-ballasted and relied on a heavy crew and luck.

Another little modification on my BR20 is a 6 inch long stainless steel wire strop between the lower mainsheet block and U-bolt anchor point on the cockpit floor.  Originally I fitted this to provide clearance between the main sheet block and two pairs of famously large borrowed oars stowed either side of it. I found the strop extension allows me to more easily disengage the mainsheet cam-cleat in moments of panic, so I have kept it even though the big oars have returned to their owner.

You may notice my attempts to reduce capsize misery risk rely on boat modifications and not improving my skill which is more difficult to remedy even with increasing cowardice as a natural consequence of gaining experience.

Matthew
BR20 Gladys



"Hilda", CLC Northeast[er], home build, epoxy ply, balanced lug
Previously "Tarika", BR17, yard built, epoxy-ply, gunter rigged
and "Gladys" BR20, GRP, gunter

Michael Rogers

I'm sending back my Crewsaver thingy, and I'll order two (to be on the safe side) of those Henshaw jobs, which I will hoist aloft, port and starboard. Never do things by halves.

Just in case there is the remotest possibility that anyone thinks I'm joking - I am, actually. The joke is emphatically on me, as I've tried to indicate. And I'll give my new windbag a go sometime. Still, as I think you, Matthew, have pointed out previously, the best approach is not to capsize in the first place. '...increasing cowardice as a natural consequence of gaining experience...' How very true, and that is my nomination for Forum Wise Saying of the Month. Ah me, I can almost remember those heady days when (nautical) innocence really was bliss. Danger? What's that when it's at home?

Michael R  (welcome, Michael N!)

Peter Taylor

Looking at the cost of the Secumar it strikes me one could make a self inflating float cheaper using an automatic lifejacket, maybe enclosed in a velcro fastened bag for neatness and weather protection. A Hamar type (e.g. £80 at Decathlon) would probably be best. At 165N it compares with about 195N for a 20l float or 88N for a 9l float.  Just a thought...
Peter

ps I second the vote for the "cowardice with experience" Wise Saying!
Peter Taylor
BayCruiser 20 "Seatern" (009)
http://www.seatern.uk

Graham W

Quote from: Matthew P on 12 Jul 2015, 22:11
I  have now more than doubled the speed of flooding the ballast tank by reversing the direction of one of the self-balers and removed the flap so when deployed it acts a forward facing scoop with a satisfyingly forceful water fountain.  As the self-balers only seem to self-bail in conditions when I want to fill the ballast tank, not empty it,  the loss of one bailer is not a problem. I have also fitted a bigger drain bung with double the cross sectional area.  Both these mods proved useful in Falmouth

Matthew,

I think that you're on to something.  The majority of posts about the ballast tank have concerned the tedious business of emptying it.  From a safety point of view, filling it quickly is much more important.  Time to make yet more holes in my boat....

Quote from: Matthew P on 12 Jul 2015, 22:11
I found the strop extension allows me to more easily disengage the mainsheet cam-cleat in moments of panic.

I've seen mentions of difficulty in disengaging the mainsheet camcleat before.  I have absolutely no problem disengaging the camcleat but engaging is more difficult and if I'm sitting out, I have to push the string in with the point of my shoe.  From a safety viewpoint, difficult cleating is probably preferable to difficult uncleating.  I changed my mainsheet setup years ago to give extra mechanical advantage (picture below) but I don't know why that would change the cleating angle.
Gunter-rigged GRP BR20 No.59 'Turaco III'

Graham W

Presumably on a gunter-rigged boat, a flotation device would need to be secured at the top of the yard, rather than halfway down at the top of the mainmast?  This would ensure that the flotation leverage (or whatever it's called) is at its greatest.
Gunter-rigged GRP BR20 No.59 'Turaco III'

Matthew P

Quote from: Graham W on 13 Jul 2015, 15:36
Presumably on a gunter-rigged boat, a flotation device would need to be secured at the top of the yard, rather than halfway down at the top of the mainmast?  This would ensure that the flotation leverage (or whatever it's called) is at its greatest.

A bit scary.  If the topmast halyard breaks or is loose or the unstayed topmast (now carrying the full righting force of the boat) breaks then there could be quite a mess.  A flotation device at the top of the stayed mast would be much more secure but of course needs to be big enough to work at lower leverage.  In any case a reefed topmast will have the same righting moment although a fully reefed boat is less likely to capsize. And all that draggy baggage right at the top of the mast is in the best place to help induce tipping in the first place. But like all engineering design it comes to a compromise between opposing options. Better engineering minds than mine would need to do the sums and/or some careful trials.  Could be a good project for an engineering student who likes maths and getting wet?

Meanwhile I'll smuggly lower my gunter rigged topmast and reduce the top hamper when reefed while I watch all the bermudan rigged boats wave their masts, sticking out at the top of the sails,  high in the air.

Matthew
(Boat name anonymous so she doesn't get volunteered for further trials)
"Hilda", CLC Northeast[er], home build, epoxy ply, balanced lug
Previously "Tarika", BR17, yard built, epoxy-ply, gunter rigged
and "Gladys" BR20, GRP, gunter

Matthew P

Sorry Graham, on reflection I was too quick to dismiss the significance of buoyancy at the peak of the sail. 

I think some time ago you suggested that one cause of turtling is the wind driving a semi-capsized hull onto the down-wind semi-submerged sail, causing it to "trip" and turtle.  If so then anything that keeps the top of the sail near the surface may prevent turtling, or at least give the crew time to react, is useful even if it is not sufficient buoyancy without other aids to recover from a full turtle.  Have I seen some dinghies with an apparently padded area in the sail at the peak that would serve this purpose?

Thinking over the circumstances of my own and other capsizes, perhaps the most fundamental issue is balancing the capsize risk against circumstances.  In a race, in relatively sheltered water, with rescue boats or at least other boats at hand I think the small risk and manageable consequences of a capsize are acceptable. So sailing un-ballasted, under-reefed with competent, robust crew wearing appropriate buoyancy aids and clothes is OK. (The Sailing Master, Andrew normally wears a dry suit and I usually wear a dry suit if I think it there is significant risk). This is basically acceptable to dinghies and an un-ballasted Bayraider should be thought of as a dinghy.

On the recent Sale Caledonia Loch Ness Challenge race Ristie beat Gladys to the North end of Ness because Tim correctly assessed the actual conditions and sailed safely most of the way down-wind without ballast until it got rough at the end and he filled his tank - is this correct Tim?

Sailing without nearby support from other boats on big open water is a different matter and capsizing cannot be risked.  So then the issue is using water ballast as a default (or at least being able to fill the tank rapidly if conditions change) and being capable of reefing quickly.  So far my modifications to fast-fill the tank have worked well and my attempts to speed reefing have not.  I'd be interested in further ideas particularly on fast reefing. 

As a lazy person I am prone to put-off doing things that require effort to undo, so being able to empty the ballast tank quickly and easily is a big incentive to filling it when needed.  So far I have fitted the biggest pump I can (a Whale Titan). My next step is to try to improve the self-bailer performance.  I know Michael and I think Bill have electric Rule pumps and it would interest me to know how well they work and how the battery power is managed.  Meanwhile thoughts are turning to building an electric pump and battery into the main ballast tank hatch. 

In conclusion, I think Bayraiders without ballast should be treated as big dinghies with the same regard to performance/risk benefit and risk mitigation.  Dare I say an occasional (every few years not every race) capsize in safely managed circumstances is acceptable. With water ballast Bayraiders are more akin to ballasted day-boats able to cope safely in rougher and more isolated conditions, if appropriate care is taken to reef early and not get caught out. Capsizing in isolated situations is not an option. 

What do you think?

Matthew
BR20 Gladys
"Hilda", CLC Northeast[er], home build, epoxy ply, balanced lug
Previously "Tarika", BR17, yard built, epoxy-ply, gunter rigged
and "Gladys" BR20, GRP, gunter

jonno

As a sailor lacking that 'certain experience', I'm informed by this useful discussion.  Further, I'd welcome the opportunity to practise capsizing.  However, in five years with Ella, there's never seemed to be an ideal time!

Why don't we have a 'capsize weekend' where some time is devoted to capsize practice?

John

steve jones

Can't help with masthead floats, but have a method for faster reefing that works for me as a single handler , I have permanently rigged a reefing line through a dumb sheeve that when the full sail is deployed carries up the gaff, when a reef is needed slack off the main halyard and drop to the reef point.
tie up the reef points and refit the sprit.
  I don't have any photos' but it can be seen on a snap taken of my boat sailing from Falmouth to Helford a couple of years ago.  When sailing in the sea I sail with a cut down mainsail and full ballast tank. That was the way it was rigged at Mylor last week. Couldn't come with you all to Malpas as I broke a couple of ribs (on me not rigid inflatable) .

Steve J.  Nona Me BR17