Split backstay tensioning ideas.

[Ceirwan]

The current setup on my Sadler 25 is single backstay which goes through a wheel tensioner and then straight to a D-Ring installed through the deck, not only is it in the way of the tiller a little bit, theres no real backing behind it other than a small alloy block and the deck hull join.

The plan is to split it at the base so it comes up from each side of the transom and joins about a couple of metres up, then becoming a single backstay, I would however like to still be able to adjust the tension of the backstay, has anyone got any ideas how to go about it? Its a masthead rig so I can't just put a block and tackle in it!

 

[Poignard]

A tackle between the legs of the inverted vee. Haul in on this to increase backstay tension.

 

[Salty John]

Like this:
View attachment 42773

 

[oldsaltoz]

Please don't ask me what it's called, but recall racing a 28 foot mono hull that what you describe, it was a simple system with two steel rollers, one one each side of the inverted 'V' and a fixed eye for the sheet down to a turning block and into a set of jaws with a lift release, much like a main sheet.

Worked very well too, quick to adjust and a simple lifting motion released it altogether.

Good luck and fair winds.

 

[Poignard]

Like this:
View attachment 42773

Mine is simpler than that (and cheaper) but probably not as powerful. The two tackle blocks are simply seized to each leg of the vee and the fall of the tackle is made off on a small shroud cleat.

 

[Ceirwan]

The twin rollers looks pretty handy, I'll get looking on ebay! Thanks for the replies.

 

[Rigger Mortice]

Plenty here http://www.harken.co.uk/content.aspx?id=3896
The cascade system taken to both quarters is easy enough to set up. It's worth putting a strop across the tackle to make sure that, if the line is accidentally allowed to run free, the whole lot doesn't let the masthead go forward.

 

[Lakesailor]

Why not just have a sheave at the end of the single backstay and a loop of rigging wire from one deck fitting over the sheave and down to the other deck fitting. Then you can use your existing tensioner in one side of the loop.

The other proffered alternatives seem to still have a central deck fitting which will, presumably, still obstruct the tiller.

 

[Ceirwan]

Why not just have a sheave at the end of the single backstay and a loop of rigging wire from one deck fitting over the sheave and down to the other deck fitting. Then you can use your existing tensioner in one side of the loop.

The other proffered alternatives seem to still have a central deck fitting which will, presumably, still obstruct the tiller.

Because its a masthead rig it relies on the backstay to stay up. I had thought of that idea, but I don't fancy relying on a sheave for something so important.

I looked at the Harken site, Instead of running the block and tackle down to the centre, I'll offset it.
http://www.ybw.com/forums/newreply.php?do=newreply&p=4767950 Same as the 8:1 version.

 

[Lakesailor]

I think you are unduly pessimistic about the strength of the blocks.
A block designed for wire will have high loadings in mind as part of it's design
Plenty of masthead rigs have split backstays using sheaves.

Harken do a range.

 

[30boat]

Because its a masthead rig it relies on the backstay to stay up. I had thought of that idea, but I don't fancy relying on a sheave for something so important.

I looked at the Harken site, Instead of running the block and tackle down to the centre, I'll offset it.
http://www.ybw.com/forums/newreply.php?do=newreply&p=4767950 Same as the 8:1 version.

Just use an oversized sheave for wire and youll be able to relax.

 

[William_H]

The 2 sheaves box squeeze together system is most common around here on mast head rigs. With the advantage that there are no sheaves in the load path for the fall back position. good lcuk olewill