Making a Bosun's Chair - anyone got any tips or plans?

[lampshuk]

I'm considering that perennial problem: getting up the mast. And down again. I have looked at some of the many postings on climbing rigs, mastaclimbas etc but for the moment am working on the assumption that I can get someone to hoist me up the mast.
The cheapest solution would be to make my own chair with some stout planks and a rope strop.
My question is about reeving the rope around the chair. I know that you need to pass the rope under and across the seat lengthways, in case the wood breaks, but how about joining the ropes together to make the hoist? Is it best to have two separate loops joined to a ring? A single line gathered at the top to make a secure loop? How long should the loop be? Any suggestions for knots etc? I looked online for some suggestions but couldn't find anything for this.

 

[alteredoutlook]

forget about the cheapest solution - yours or your crews safety is the first thing you should consider.

Buy a proper climbing harness for your ease of mind.

 

[Graham_Wright]

forget about the cheapest solution - yours or your crews safety is the first thing you should consider.

Buy a proper climbing harness for your ease of mind.

+1 or a chair BUT try it before you buy it.

 

[sarabande]

the longer the plank, the more the strain on the support rope.

The aim shoud be to have resilience in the system, so that if one component fails, there is a backup capable of supporting the person.

I'd get the point of attachment to the halyard to be halfway between the chin and the breastbone; this will enable you to have a line which clips round the chest under the arms and back to the attachment point, thus making sure that the CofG of the person is below the attachment point. A lift point at mid chest height means you can reach the top of the mast with your hands.

I spent a long time fiddling with a plank, drilling holes, backsplices, crown knots, eye splices round shackles, etc. In the end I had a heavy chunk of wood with about 8 metres of 12mm polyester. Difficult to store and not quick to activate.

I now have a seat and harness made from very heavy duty nylon. It also has a deep pocket each side, so that you can store screwdriver/batteries, spare cable, oil, whatver you need. The only modification is another shackle at the top to take a spare halyard.

 

[prv]

I used a single length of rope to form the two loops, crossing under the plank. The knot was a climber's figure-8 under the plank, with long tails each side taped to the standing part of the rope to prevent any possibility of them pulling through the knot. For the loop at the top, I gathered the lines together at the appropriate point and put a seizing round all four parts - this seizing is of course not load-bearing, it just stops things sliding around.

I look bemusedly at the people who automatically put more faith in sweatshop stitching than their own ability to tie a simple knot. But on the "no single point of failure" principle, I do also wear a scaffolder's fall-arrest harness to secure my backup line.

Pete

 

[pete]

The trouble with a board is that when you try to assist the wincher by climbing you slide off the board.
I made one using wide webbing and material stitched together that you had to step into, with a buckle to prevent you slipping or falling out. I was recently given a unused commercial one that had had to be written off due to it being over 5 years old. There should be plenty out there perfectly OK and just gone out of date.

 

[Quandary]

I have been to the top of our mast twice in the last two days, the first time I was up there for over an hour, the second was not quite as long, but I both times I was glad to get back down feeling stiff and tired, so I would suggest buying a decent bosuns chair with a pocket for bit of ply in the seat so that you can work with two hands with comfort and confidence. We have discontinuous rigging so I will be up again for a bit of tuning to that and that involves working out at the spreader tips. I have been up masts not quite as tall as our current one on makeshift planks etc. but if you have a problem that requires time and concentration you want the proper item. As a pessimist who can only overcome vertigo on a yacht mast, even today, if I anticipate a long job I put on a harness and secure it to the mast crane while I am working. I suppose sitting on a bit of plank to do work up there is much easier for those who do not share my vertigo.

 

[AngusMcDoon]

The cheapest solution would be to make my own chair with some stout planks and a rope strop.

Not worth the risk for £26, in my opinion.

http://www.ellis-brigham.com/produc...ode=88229902&gclid=CMCzi6XShb4CFWzJtAodi2AA1Q

 

[Daydream believer]

I have been up the masts of my boats several times each year for various jobs
I used to have a plank & now have a stitched seat only because someone gave it to me
The plank is better in every way. I am always worried that the stitching will fail with a fabric harness.
Because of that I tend to pass a line under the seat to catch me if the seat tears
The plank needs to be about 3-4 inches longer than the width of your hips.
The holes can be about 1-1.5 inches in from the end. It allows the lines to nip you in a bit & helps one feel safer
The seat would be a piece of prepared timber or ply about 5.75 inches by 1 inch with rounded edges
You can adjust the loops to suit . I prefer shorter loops so I am clamped in better but I do tie a line to the uphaul , pass it over my left shoulder & back under the right armpit & back to the uphaul. I fix one end with a slip knot so i can adjust it when up the mast. This means i can lean back without feeling I am going to topple out. I do the same for a fabric chair.
If the loop is not too big I can pull it( or at least my crew on the winch can) right up to the top of the mast & can easily work on the top without any rigs to let me to stand up.

 

[prv]

Not worth the risk for £26, in my opinion.

Risk of what?

http://www.ellis-brigham.com/produc...ode=88229902&gclid=CMCzi6XShb4CFWzJtAodi2AA1Q

Looks good for catching you in a fall, but quite uncomfortable to sit in for any length of time.

Pete

 

[PlankWalker]

I have used the same oak plank now for 35 years, have changed the 12mm polyester though.

4 holes in each corner of a 9" plank of length to suit the width of your rear.

Double fishermans bend in the crossed over 12mm polyester underneath, keep this line as short as possible such that it doesn't pinch the thighs too much when its loaded

No splicing or stitching anywhere, just a double sheetbend with the halyard through the 2 loops at the top. Never use a shackel.

 

[AngusMcDoon]

Risk of what?

Looks good for catching you in a fall, but quite uncomfortable to sit in for any length of time.

A climbing harness might be uncomfortable, but not nearly as unpleasant as hitting a deck from 50' up. In my opinion a climbing harness holds the occupant more securely, but each to their own.

 

[Heckler]

Plus one!
PS what do you think of this circuit, how difficult to build? http://www.fmsh.com/xqitadmin/uploadFiles/20120306035007.pdf
Stu

 

[neil1967]

? what relevance to climbing masts?

 

[RichardS]

? what relevance to climbing masts?

Picking up an ignition controller is the next best thing to picking up a crew member?

Richard

 

[AngusMcDoon]

PS what do you think of this circuit, how difficult to build? http://www.fmsh.com/xqitadmin/uploadFiles/20120306035007.pdf

Really tricky at the top of a mast dangling in a bosun's chair or getting your plums squished in a climbing harness, especially if surface mount.

 

[Trop Cher]

Not worth the risk for £26, in my opinion.

http://www.ellis-brigham.com/produc...ode=88229902&gclid=CMCzi6XShb4CFWzJtAodi2AA1Q

Looks good until you come to their sizing chart, oh dear

Small: 28-31" waist
Medium: 30-33" waist
Large: 32-35" waist
Extra Large: 34-37" waist

 

[Halo]

I made mine a few years ago. Strong plank with separate ropes going under the seat diagonally. Works like a charm. I have a separate safety line also. I expect the real hazard is line or mast failure (or incompetant winch operation) rather than the seat giving up. Not sure of the advantages of something made by others and I have more faith in my own work rather than others who are probably making to tight margins and times in producing goods

 

[AngusMcDoon]

Not sure of the advantages of something made by others and I have more faith in my own work rather than others who are probably making to tight margins and times in producing goods

Does that apply to pyrotechnics as well? I suspect that if there were shoddy unsafe products made by companies like Black Diamond they would very soon be out of business and facing large compensation claims. I find it remarkable that anyone can think that some bodged up bit of wood and rope is going to be better made than a tested, certified professionally manufactured product by an established company with a reputation to protect. If you said that you wanted to make your own bosun's chair to save some money, well, being from Yorkshire, I could understand, but to claim that it's safer than a professionally made climbing harness - I don't agree with that. But it's your life at risk and your choice.

 

[John the kiwi]

Does that apply to pyrotechnics as well? I suspect that if there were shoddy unsafe products made by companies like Black Diamond they would very soon be out of business and facing large compensation claims. I find it remarkable that anyone can think that some bodged up bit of wood and rope is going to be better made than a tested, certified professionally manufactured product by an established company with a reputation to protect. If you said that you wanted to make your own bosun's chair to save some money, well, being from Yorkshire, I could understand, but to claim that it's safer than a professionally made climbing harness - I don't agree with that. But it's your life at risk and your choice.

This forum is Practical Boat Owner. Built on proud traditions of sailors building their own stuff cos they can do it better than store bought. Cheaper too, sometimes!
I am astonished at your take on this thread.
Why dont you leave the electronics to the big company experts?
After all risk of death from failure of "bodged up" navigation electronics as compared to a using a "tested, certified professionally manufactured product by an established company with a reputation to protect" is possibly greater than the risk of a self made bosuns chair.

Sadly, established companies with reputations to protect also employ low cost labour who don't have any vested interest in the quality of the products.
Sometimes the quality guy takes his eye off the ball too. People fail to do what they should. It happens all the time. There would be no plane crashes otherwise.
In the end, i would rather trust something I "bodged up" than a budget device of uncertain origin from a discount chandlery.
I do however have the skills, training and experience to make a value judgement of the relative merits of such things as harnesses.

OTOH, though passingly competent with a soldering iron, i would rather leave the electronics to the experts.
I guess it is the other way round with you?

cheers