GP14 Sailing › Forums › Forum › Forestay Failure
- This topic has 2 replies, 1 voice, and was last updated 10 years, 7 months ago by Oliver Shaw.
-
AuthorPosts
-
-
13/02/2014 at 1:40 pm #3679Oliver ShawModerator
<p id=”yui_3_14_0_3_1392297643035_14″>All the real load is taken on the genoa halliard, and the forestay is there only to keep the mast up while the boat is in the boat park; right?</p>
<p id=”yui_3_14_0_3_1392297643035_12″></p>
<p id=”yui_3_14_0_3_1392297643035_8″>Er, … … OK, it is also to support the mast in the event of needing to sail under main alone, with no headsail hoisted. But that situation won’t arise with a fully furling headsail that is left mounted whenever the boat is on the water. Right?</p>
<p id=”yui_3_14_0_1_1392297643035_1597″></p>
<p id=”yui_3_14_0_3_1392297643035_16″>Well, last night we got what the BBC news is describing today as hurricane force winds. Actually I thought the forecast had been “only” force 10, and I haven’t been conveniently able to check the actuality, but force 10 is quite enough.</p>
<p id=”yui_3_14_0_1_1392297643035_1624″></p>
<p id=”yui_3_14_0_3_1392297643035_20″>I spent the morning at home repairing a fence that had blown down, which was no great surprise in the circumstances. Then I picked up a message from the sailing club to alert me to chaos in the boat park; covers torn, boats upside down, and other damage. I actually got away quite lightly; <em id=”yui_3_14_0_3_1392297643035_25″>A Capella was very well tied down to a pair of substantial ground anchors – although one of them has started to pull out of the ground, but the forestay had snapped. I regard it as pure luck that the mast was not damaged as a result; I can only think that with the boom up and with a tie down strap over everything (and thus pulling downwards on the boom) the boom acted as a brace between mast and transom, and thus gave sufficient support to save the mast.</p>
<p id=”yui_3_14_0_3_1392297643035_60″></p>
<p id=”yui_3_14_0_3_1392297643035_28″>The forestay was in good condition, and the wire parted in mid span; not at one of the terminations, and not the lanyard at the bottom.</p>
<p id=”yui_3_14_0_3_1392297643035_62″></p>
<p id=”yui_3_14_0_3_1392297643035_32″>This was just with the bare mast up.</p>
<p id=”yui_3_14_0_1_1392297643035_1621″></p>
<p id=”yui_3_14_0_3_1392297643035_36″>When I started sailing GP14s, in the sixties, it was normal for forestays to be of the same diameter as the shrouds. Modern practice seems to be to use thinner wire for the forestay; my quick measurements today give 2 mm diameter for the forestay and 3 mm for the shrouds. Those measurements are reasonably accurate, although I did not bother to use the vernier scale for greater precision; if they are exact then the forestay has just under half the cross sectional area – <strong id=”yui_3_14_0_3_1392297643035_41″><span id=”yui_3_14_0_3_1392297643035_70″ style=”text-decoration: underline;”>and thus just under half the strength</span> – of the shrouds.</p>
<p id=”yui_3_14_0_1_1392297643035_1622″></p>
<p id=”yui_3_14_0_3_1392297643035_49″>I am not prepared to risk the mast, so my replacement forestay will be 3 mm …</p>
<p id=”yui_3_14_0_3_1392297643035_66″></p>
<p id=”yui_3_14_0_1_1392297643035_1623″></p>
<p id=”yui_3_14_0_3_1392297643035_53″>Oliver</p> -
13/02/2014 at 2:01 pm #3680Oliver ShawModerator
Oh dear, formatting gobbledegook; the website appears not to accept copy and paste, although everything looks perfect in the typing window. Let’s try again.
All the real load is taken on the genoa halliard, and the forestay is there only to keep the mast up while the boat is in the boat park; right?
Er, … … OK, it is also to support the mast in the event of needing to sail under main alone, with no headsail hoisted. But that situation is never going to arise with a fully furling headsail that is always left up (but furled when appropriate) whenever the boat is on the water. Right?
Well, last night we got what the BBC news is describing today as hurricane force winds. Actually I thought the forecast had been “only” force 10, and I haven’t been conveniently able to check the actuality, but force 10 is quite enough.
I spent the morning at home repairing a fence that had blown down, which is no great surprise in the circumstances. Then I picked up a message from the sailing club to alert me to chaos in the boat park; covers torn, boats upside down, and other damage. I actually got away quite lightly; A Capella was very well tied down to a pair of substantial ground anchors – although one of them has started to pull out of the ground, but the forestay had snapped. I regard it as pure luck that the mast was not damaged as a result; I can only think that with the boom up and with a tie down strap over everything (and thus pulling downwards on the boom) the boom acted as a brace between mast and transom, and thus gave sufficient support to save the mast.
The forestay was in good condition, and the wire parted in mid span; not at one of the terminations, and not the lanyard at the bottom.
This was just with the bare mast up.
When I started sailing GP14s, in teh sixties, it was normal for forestays to be of the same diameter as the shrouds. Modern practice seems to be to use thinner wire for the forestay; my quick measurements today give 2 mm diameter for the forestay and 3 mm for the shrouds. Those measurements are reasonably accurate, although I did bother to use the vernier scale for greater precision; if they are exact then the forestay has just under half the cross sectional area – and thus just under half the strength – of the shrouds.
I am not prepared to risk the mast, so my replacement forestay will be 3 mm …
Oliver
-
13/02/2014 at 7:30 pm #3681Oliver ShawModerator
Steve White wonders whether it was hit by flying debris in the general melee, which is entirely possible although there was nothing obvious on the ground.
And I stand corrected on the wind force; I am told that the Coastguard recorded 86 mph, which is well into force 12!
Oliver
-
-
AuthorPosts
- You must be logged in to reply to this topic.