Going aloft on a small boat

Reptile Smile

Reptile Smile

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Hi all,

I have a Hurley 20 to which I want to fit the Barton lazy jack system. There are, in general, 2 choices - drop the rig, or go aloft. I haven't quite made my mind up, but want to know my choices anyway - is there such a thing as a rig that is too insubstantial to go aloft on? And is it mine..? :-)

Cheers
 
Assuming the mast isn't very tall on a 20 footer, why not use a shortish ladder lashed to the mast? You probably only need to reach 1/2 or 2/3 way up anyway.
 
Reptile Smile said:
Hi all,

I have a Hurley 20 to which I want to fit the Barton lazy jack system. There are, in general, 2 choices - drop the rig, or go aloft. I haven't quite made my mind up, but want to know my choices anyway - is there such a thing as a rig that is too insubstantial to go aloft on? And is it mine..? :-)

Cheers
Click to expand...

Based in Bristol with a 14 metre tide, there are options!
 
I looked at the Barton system but the blocks and rope size are far to big. Cost a lot too! I just got a couple of small Seasure plactic blocks (to avoide chaff on the sails), 4mm white cord, six eye fixings and a cleat. Total cost about £20 but the main thing is that it is far neater and easier to handle than the thisck oversized Barton option.

As for the hight, as already mentioned should probably be fixed to the mast just above the spreaders.
 
I have a Hurley 24 and no way would I go up, or send someone, on the running rigging.
Lots of yards will get you up on a crane wire, either in a harness or a little platform, a neat solution.
 
Ive been up the mast on my 22ft E-Boat. Its a slim mast too. I climbed up to the spreaders without a rope to rescue a flag halyard, just like climbing a pole!
Ive also used a ladder lashed to the boat in various ways so it cant move. I also tied the halyards to the pontoons either side of me to stop her rolling, which worked well. Its a bit more tender than regular yachts, but it can be done carefully. Ive been up a few times like this, but never to the top. I'd drop the mast for that.
I can drop the mast in 20 mins, but its putting it back up and tensioning and tuning after re-stepping that takes the time.
 
Reptile Smile said:
I have a Hurley 20 to which I want to fit the Barton lazy jack system. There are, in general, 2 choices - drop the rig, or go aloft. I haven't quite made my mind up, but want to know my choices anyway - is there such a thing as a rig that is too insubstantial to go aloft on? And is it mine..? :-)
Click to expand...

I wouldn't worry much about the strength of mast or stays, but I would worry about the stability of the boat. My last boat had a 26' long mast with its foot about 4' above the metacentre and a 500 kg keel with its centre about 4' below the metacentre so 60 kg dangling from the mast head would be enough to overcome pendulum stability, leaving only form stability to keep things upright.

I never dared even trying it; instead I got quite adept, though I say so myself, at lowering and raising the mast on my own while afloat.
 
I've been to the top of the mast on our First 235 - fractional rig and bendy 29' stick. Used a mast climbing ladder hoisted up the mainsail track and a harness / couple of halyards for safety. The rig is easily strong enough and there were no problems with stability. The boat has a 350kg swing keel - just under 6' draft. I weigh 70kg. The hull has plenty of form stability. Obviously I chose a calm day but plenty of mobos sped past - almost seemed like more than usual! :rolleyes:
 
I have been up the mast of a few boats.
The limit is definitely the stability of the boat.
I've seen a 20ft racing keelboat close to capsize due to a bloke up the mast, but I've been up to retrieve a spinny halyard during a race.
To get up to spreader height, a ladder while secured alongside would be fine, so long as you are away from wash.
If you can arrange for the keel to be in a bit of mud that can help too!
Anything higher, I'd take the mast down instead.
 
When I first started sailing I was convinced I was afraid of heights, then when out racing one night in about force 5 in our Achilles 24, the spinnaker would not come down, halyard had jumped the sheave, I was faced with the choice of going across the N channel or up the mast. I was up for about half an hour while another yacht stood by us (too mean to cut the halyard and I was not sure I would ever be up again) and I felt quite quite seasick by the time I got down but it had cured my vertigo. It also convinced me that it would take a lot more than my 13 stone to pull any keel boat over. I was up again in harbour a week later and am up at least twice a year since as I hate having to pay to replace stuff damaged by the crane so it goes on after stepping.
We used to try to winch our Trapper 300, a notoriously tender boat, over in the river to scrub the bottom when winter racing, just managed to break halyards or pull trees out when it got to about 30 degrees of heel.
 
Reptile Smile said:
Hi all,

I have a Hurley 20 to which I want to fit the Barton lazy jack system. There are, in general, 2 choices - drop the rig, or go aloft. I haven't quite made my mind up, but want to know my choices anyway - is there such a thing as a rig that is too insubstantial to go aloft on? And is it mine..? :-)

Cheers
Click to expand...
A Hurley 20 is both smaller and much less beamy (less form stability) than the boats quoted where owners say they have climbed the mast. I certainly would not try it: this boat size is one where both the stability is dubious and also the halliards, turning blocks, cleats etc will not be that heavy duty.

Surely in Bristol docks there are plenty of quaysides where you could easily pull the mast in to the quayside at spreader/just above height. Or lower the mast.
 
Just past the amphitheatre in Bristol docks there is a pretty high wall you can moor against. On my Sabre the mast was just too high to get to the bit I wanted to reach. With a smaller mast and a line to tip the boat a little it might be possible to reach. You don't need to get all the way up for lazy jacks
 
Agreed that it would be much easier to pull the mast over to a convenient quayside, but I'm just curious as to whether it would actually be dangerous to go up as far as the spreaders on this particular boat.

Is anyone clever enough to do the sums on this? The boat's specs are here: http://sailboatdata.com/viewrecord.asp?class_id=4423

It actually has a lot of ballast for the size of boat - 454kg. It's also pretty beamy at 7' 8". The mast is 24' 6" and the spreaders look to be about 2/3 of the way up. The bilge keel version only has a draft of 2 1/2 feet though which means not much of a righting lever.

Edit - agree with the comment on the strength of blocks, cleats etc on a boat this size / age, I'm purely asking from a stability point of view.
 
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If two people pulling on a halyard from the quayside can bring the mast down, problem solved; if they can not, which is a lot more likely, one of them up the mast will not overturn it either.
If sail boat is so unstable that one persons weight above the hull can exert enough moment to bring the mast down, what happens if the sails are up in force 4?
 
What a load of wimps.

I used a spare halyard to hoist a double extended alloy ladder to the top of the mast and tied the foot to the foredeck bollard. I needed to alter the halyard lead to the bobbin on the furler.
The boat is a Valiant 18. Unless you are going to get your body weight outboard of the gunwhales there is no risk. I had a friend on the jetty to stabilise the boat as if the ferries go past it there is some wash.

Just before I got the ladder on board

SubstituteMast.jpg
 
No need to guess

mrming said:
...The boat's specs are here: http://sailboatdata.com/viewrecord.asp?class_id=4423...
Click to expand...

You can't work out the form stability from this data alone, but has anybody got a GZ (or preferably RM) curve for the Hurley 20? If so, it's quite easy to overlay the Righting Moment curve and the moment of a person up the mast as a function of angle of heel.

The moment of the person up the mast is of the form g x M x L x sin(theta), where:

g is the acceleration due to gravity (9.81 m/s/s)
M is the person's mass in kg
L is how far above the rotation point (approximately the water line) the person is
theta is the heel angle.

As long as the moment of the person is less than the righting moment as shown by the GZ curve then the boat won't capsize.

There may be an angle above which the moment of the person aloft is greater than the righting moment, but up to this critical angle of heel the boat will right itself.

Edit: here's one I prepared later! it's for an Elan 210 because I had the GZ curve available.
Stability and Heeling of Elan 210.jpg

It shows that the inherent righting moment of the Elan in blue and the heeling moment from an 85kg weight 5m above sea level in red.

As you can see the boat will self right until heeled over beyond about 78 degrees, so no problem climbing that high up the mast. It gets commensurately less stable as you go higher.

The same calculation can be done for the Hurley (or any other boat) given the appropriate righting moment curve.
 
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