Am I too fat to go up the mast ?

Re:Compression Loading

I think when the boat is sailing in anything over force 4 the side loading and resulting compression loading will far exceed your mass. Try a small experiment with SWMBO scales a stick and a piece of string. Put a tangential force on the stick with it stayed and see what happens to the scale reading!

Have you caried out a risk assessment? Mast Climb vs Mast Lowering which will be different for different boats and different folks.

Stay safe!
Trevor

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It is a light mast why not

take it down and maintain it properly?

I take both mine down every year (and they are 50 footers) and have very little problem doing so, just park under a crane or de-masting ladder and lift them/it out. Or with a small mast lean against a wall at low tide and do it even easier.

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Re:Compression Loading

I'm not sure that would be a fair analogy!

You'd need a stick that was already pressing down hard on the scales by virtue of being held by several stays before you started applying your load. I think (but I could be wrong!) that as you put a side load on the stick (and remember it will be a uniformly distributed load from the sail, not a point load applied at the top), the windward stays will get tighter and the leeward stays will get slacker and the downward component of the tension in the stays acting down the mast will remain about the same.

Any thoughts anyone?



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Re:Compression Loading

Yes, thats true, untill the leeward stay is more or less slack (which actually happens at quite a low wind speed, though not to the extent that the stays visibly flapping around). Any additional wind load ater that loads up the windward stay without further unloading the leward stay, so the compression forces on the mast increase.

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We tried this on a 26ft Hunter last year in a marina,we got him about 5ft off the deck before his bottle went.The mast did not look very happy but it could have been an optical illusion,the main worry was the flexing and groaning of the winch and surrounding deck.We found it simpler to drop the mast

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Re: Not at all ..

Reminds me of Gerard Hoffnung & the bricklayer

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like this?

Dear Sir,

I am writing in response to your request for additional information in Block 3 of the accident report form. I put "poor planning" as the cause of my accident. You asked for a fuller explanation and I trust the following details will be sufficient.

I am a bricklayer by trade. On the day of the accident, I was working alone on the roof of a new six-story building.

When I completed my work, I found that I had some bricks left over which, when weighed later were found to be slightly in excess of 500lbs. Rather than carry the bricks down by hand, decided to lower them in a barrel by using a pulley, which was attached to the side of the building on the sixth floor.

Securing the rope at ground I went up to the roof, swung the barrel out and loaded the bricks into it. Then I went down and untied the rope, holding it tightly to ensure a slow descent of the bricks. You will note in Block 11 of the accident report form that I weigh135lbs.

Due to my surprise at being jerked off the ground so suddenly, I lost my presence of mind and forgot to let go of the rope. Needless to say, I proceeded at a rapid rate up the side of the building.

In the vicinity of the third floor, I met the barrel, which was now proceeding downward at an equally impressive speed. This explained the fractured skull, minor abrasions and the broken collar bone, as listed in section 3 of the accident report form.

Slowed only slightly, I continued my rapid ascent, not stopping until the fingers of my right hand were two knuckles deep into the pulley. Fortunately by this time I had regained my presence of mind and was able to hold tightly to the rope, in spite of beginning to experience pain. At approximately the same time, however, the barrel of bricks hit the ground and the bottom fell out of the barrel.

Now devoid of the weight of the bricks, that barrel weighed approximately 50 lbs. I refer you again to my weight. As you can imagine, I began a rapid descent, down the side of the building.

In the vicinity of the third floor, I met the barrel coming up. This accounts for the two fractured ankles, broken tooth and several lacerations of my legs and lower body. Here my luck began to change slightly. The encounter with the barrel seemed to slow me enough to lessen my injuries when I fell into the pile of bricks and fortunately only three vertebrae were cracked.

I am sorry to report, however, as I lay there on the pile of bricks, in pain, unable to move, I again lost my composure and presence of mind and let go of the rope and I lay there watching the empty barrel begin its journey back down onto me. This explains the two broken legs.

I hope this answers your inquiry.

Kind Regards,
Mike Pashby





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Re:Compression Loading

Ahhhhh!

OK, that makes sense. I'll have a look next time I'm hard on the wind and see what sort of windspeed it takes to ease the tension on them. I have heard of people who tighten their rigging as much as they can and then go out hard on the wind and re-tighten the leeward shrouds, tack and re-tighten the other side while they're still sailing. I've never been brave enough to do this to my coachroof though!

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1. By stating there is "current going up the mast" there must be an electrical ciruit. Lamp bulbs normally fail open circuit so you could have an electrical leakge path in the wiring with the resultant voltage across the lamp bulb too low for it to illuminate.

2. No, from my experience on a similar sized yacht, you are not too heavy to go up the mast and a fit 8+ stone lady should be able to winch you up. However, do it when afloat.

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Re: like this?

The barrel being heavier it started down once more
And landed right across me there as I lay on the floor
It broke three ribs and my right arm
And I'm very sad to say
That I hope you'll understand why Paddy's not at work today.

<hr width=100% size=1>regards
Claymore
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