Halyard stretch

[Brian D]

Sunday I was going to go up my mast to replace the steaming light bulb. But before doing so, I wanted to test my jib halyard. So I formed a loop with a bowline knot, raised the halyard about 2' and stepped into the loop. I was taken aback by how much the haryard stretched. About 1.5'. So I decided not to go up the mast.Would this be considered normal stretching? I don't know exactly what kind of line it is so I can't give any info. I weigh about 220 (must... lose... wight...).Thoughts?ps, I was going to tie off another line to the halyard and use my ATN Top Climber.

 

[Steve O.]

not normal

I suspect that you do not have the right type of line for your halyard. You might want to remedy this situation.

 

[Joe]

sounds like nylon....

... change over to a polyester type. Drop by San Diego Sailing Supply in Pt Loma for their help.

 

[Larry Wilson]

Not really that much stretch

All things considered, that's not that much stretch. Keep in mind, that if you have a 60 foot long main halyard, your percentage of stretch was only 5%. The newer yachtbraids will be in the 1.5 to 2.5 range. Once you've raised your main, tensioned the halyard, you will only have 50% of the total length, so that 18" is now only 9" or less.

 

[Brian D]

So Larry...

If I connect the line that is attached to my ATN and run it all the way up the mast, the stretch will be less that when the halyard is near the deck? I think I worded that correctly. So I really don't have much to worry about except not tying a good knot?

 

[Moody Buccaneer]

Sounds like normal stretch to me

As Larry says, that's only about 5%Standard yacht braid (double braid polyester) will stretch 5% at about 17% of rated load.The fact that your halyard stretched 1.5 ft just means that your 220# is between 15% and 20% of the ropes rated strength. You have a 5:1 static safety margin. On a 27 foot boat the halyard is probably 5/16" or 3/8". If it's 3/8" and stretched that much it's low quality line.For lifting humans, I like to see a 20:1 static safety margin. For 220# guys like us (must loose weight) that means a halyard that is rated 4400#. In Dacron double braid that means at least 3/8" diameter (3750#) or 7/16" diameter (5500#).In Spectra that's 1/4" (4300#) or 5/16" (7400#)5/32" wire at 2400# is marginal, 7/32" at 5000# is better.If the halyard was 5/16 Spectra it would have stretched less than 1% of it's length or about 5"

 

[Alan]

Double braid polyester...

...is next to the worst line to use for a halyard. Stretch is a critical spec of any halyard. It is a major factor in sail shape. Double braid poly has far too much stretch characteristic to make a good halyard. A spectra cored line like Samson XLS is a much better choice. It will only stretch .5% at 10% of rated load, and .8% at 20%. On a typical 50' mast with a 220# load on a 3/8" line that would translate into about 4" of stretch. Still too much for proper sail shaping but far better than the 1.5 feet of poly(db).However, a more critical question is: how old is that halyard? If it is more than 5 years old, you shouldn't be using it for safety purposes. I carry a dedicated climbing line that is used exclusively for that purpose. Pulling it through with the halyard is an easy way to replace. Then when done pull the halyard back again. Think about it, it's ONLY you thats going up there!

 

[Brian D]

I do want to replace my halyards...

So I might just wait until I do that before going up the mast. I think it will make me feel a little more secure.Thanks all.