Mast head Sheaves
Posted: Thu Apr 12, 2018 3:32 pm
Hello all,
To be lifted back in I need to get the backstay off. Now, once launched, in order to get the backstay back far enough to get it on, I use the topping lift to pull the mast back, reattach the backstay and I am done.
I cranked it up quite tight on the winch this time, not thinking too much of it (and thinking back, i didn't winch it on the centreline, it was off centre to port slightly as I couldn't make the topping lift up onto the pushpit at the centre because of the liferaft), did up the backstay, and then when I came to release the topping lift the stretch came out of the rope, however, the rope remained tight!
I tried pulling from both ends, if I pulled the mast end piece mightily hard, it would edge about 3 inches with a bit of a bang and a jump. If I pulled from the boom end, I couldn't get the rope moving at all.
This rope is on a sheave outside the mast. Is this a trip up the mast I'm looking at? What do you think has happened? Anything else I can try before sprinting up on my Top Climber?
![Image](https://i.imgur.com/AnfHXK2l.png)
![Image](https://i.imgur.com/4KghPK0l.png)
![Image](https://i.imgur.com/iF6qFA2l.png)
Looking back at my old photos, I bet the sheave is an old Tufnol one and thats blown apart, split in two and has eaten the rope? See the below from where I replace the main sheet sheave, but NOT the topping lift one!
![Image](https://i.imgur.com/jSmxGF0l.png)
Does anyone know the size of these sheaves so I can order one before I go aloft?? (One trip up is easier than two!)
To be lifted back in I need to get the backstay off. Now, once launched, in order to get the backstay back far enough to get it on, I use the topping lift to pull the mast back, reattach the backstay and I am done.
I cranked it up quite tight on the winch this time, not thinking too much of it (and thinking back, i didn't winch it on the centreline, it was off centre to port slightly as I couldn't make the topping lift up onto the pushpit at the centre because of the liferaft), did up the backstay, and then when I came to release the topping lift the stretch came out of the rope, however, the rope remained tight!
I tried pulling from both ends, if I pulled the mast end piece mightily hard, it would edge about 3 inches with a bit of a bang and a jump. If I pulled from the boom end, I couldn't get the rope moving at all.
This rope is on a sheave outside the mast. Is this a trip up the mast I'm looking at? What do you think has happened? Anything else I can try before sprinting up on my Top Climber?
![Image](https://i.imgur.com/AnfHXK2l.png)
![Image](https://i.imgur.com/4KghPK0l.png)
![Image](https://i.imgur.com/iF6qFA2l.png)
Looking back at my old photos, I bet the sheave is an old Tufnol one and thats blown apart, split in two and has eaten the rope? See the below from where I replace the main sheet sheave, but NOT the topping lift one!
![Image](https://i.imgur.com/jSmxGF0l.png)
Does anyone know the size of these sheaves so I can order one before I go aloft?? (One trip up is easier than two!)