Rotostay upgrade

Poignard

Poignard

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I have an early Rotostay furling system, the type where the wire halyard leads from the head of the sail up to a sheave in the top swivel, then down the front of the foil to an eye on the drum.

http://www.catamaransite.com/Boats/article/rotostay_furler/rotostay_005.gif

I want to upgrade this to the later type where the head of the sail is shackled to a slider/swivel which is pulled up the foil by a rope halyard which passes over a sheave at the masthead and then down the mast to a cleat.

I have acquired a slider/swivel but I will also need the cap that fits at the top of the foil and prevents the slider/swivel being pulled up so far that it comes off the foil.

Does anyone have one of these caps to sell me? Or failing that, can anyone let me have a photo or drawing of this cap so I can make one?
 
parsifal said:
I have an early Rotostay furling system.........

I want to upgrade this to the later type where the head of the sail is shackled to a slider/swivel which is pulled up the foil by a rope halyard which passes over a sheave at the masthead and then down the mast to a cleat.

I have acquired a slider/swivel but I will also need the cap that fits at the top of the foil and prevents the slider/swivel being pulled up so far that it comes off the foil.
Click to expand...
It will be easy to improvise a stop to retain the swivel. Normally the sail will prevent it pulling to the vey top anyway.
BUT

You may also need to seriously modify the drum assembly so that there is a bearing on which the drum and foil rotates and which transmits the tension in the halyard and luff to the seem head otherwise you will simply pull the whole shooting match up the forestay.
 
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parsifal said:
I have an early Rotostay furling system, the type where the wire halyard leads from the head of the sail up to a sheave in the top swivel, then down the front of the foil to an eye on the drum.

http://www.catamaransite.com/Boats/article/rotostay_furler/rotostay_005.gif

I want to upgrade this to the later type where the head of the sail is shackled to a slider/swivel which is pulled up the foil by a rope halyard which passes over a sheave at the masthead and then down the mast to a cleat.

I have acquired a slider/swivel but I will also need the cap that fits at the top of the foil and prevents the slider/swivel being pulled up so far that it comes off the foil.

Does anyone have one of these caps to sell me? Or failing that, can anyone let me have a photo or drawing of this cap so I can make one?
Click to expand...

The later version has a big problem of halyard wrap round the foil - I know because I fitted the E version in 1993 - to replace the somewhat undersized original. You will therefore need a deflector fitted to the mast (ideally one with built-in rollers).

The Rotostay is well worth preserving - mine has done about 28Knm and, when the forestay was replaced this September, the rigger commented favourably on how much better it had lasted than the Furlex with which he usually grappled. I did turn up a new upper bearing in acetal - the old one, running on the shaft of the top clevis was utterly worn out and the top fork was a Norseman as you cannot get the new forestay past the foil joiners without attempting (very inadvisedly) to disassemble the foil.
The "cap" to which you refer is that very top bearing, firmly and permanently attached to the top section of the foil. So you'll need to involve a machine shop.

Bonne chance.
 
VicS said:
It will be easy to improvise a stop to retain the swivel. Normally the sail will prevent it pulling to the vey top anyway.
BUT

You may also need to seriously modify the drum assembly so that there is a bearing on which the drum and foil rotates and which transmits the tension in the halyard and luff to the seem head otherwise you will simply pull the whole shooting match up the forestay.
Click to expand...


The lower, ball bearing, merely takes the weight of the foil, Vic.
The top bearing is the part that prevents the whole foil moving up the forestay. Thus length of foil compared to length of forestay is a critical match.
There are major differences between the early and E type Rotostay, the biggest is that the later E type has a clockwise direction of unrolling and anti-clockwise for rolling - or the drum unscrews - the early one is unhanded and the drum a pig to remove.
I fear that the OP may be carrying Colin Chapman's dictum of "simplificate and add lightness" a step too far.
However a valid point which, I think, the OP has overlooked.
 
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charles_reed said:
The lower, ball bearing, merely takes the weight of the foil, Vic.
The top bearing is the part that prevents the whole foil moving up the forestay. .
Click to expand...

Will the early type that the Op has have such a bearing or is it something that will also have to be added.
There will be no need for it if the halyard falls back down the spar.

I was thinking he might need something like the Plastimo gear or even the Rotostay E

I doubt if the conversion will be as simple as just add ing the swivel and an end cap
 
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charles_reed said:
The later version has a big problem of halyard wrap round the foil - I know because I fitted the E version in 1993 - to replace the somewhat undersized original. You will therefore need a deflector fitted to the mast (ideally one with built-in rollers).

Bonne chance.
Click to expand...

Fitting a small block to an appropriate point on the mast so that it holds the halyard away from the foil will both stop the halyard wrapping (as above, and in rotostay's installation instructions) and have the effect that you won't need much of a cap as you won't be able to pull sheave or sail off the top .. so maybe just running bolt or clevis pin through will do you.
 
I have just taken apart the Rotostay 2 with the top stopper you mention,
it is not a stopper as it is only a push fit on the foil, as said above your luff length stops the guide coming off.

I am having to replace the system as there is quite a lot of corrosion on the inside of the foil as the last installer did not fit a plastic covered forestay.
Bit of a bummer as all the bearings etc. are in really good order
 
saltylegs said:
I have just taken apart the Rotostay 2 with the top stopper you mention,
it is not a stopper as it is only a push fit on the foil, as said above your luff length stops the guide coming off.

I am having to replace the system as there is quite a lot of corrosion on the inside of the foil as the last installer did not fit a plastic covered forestay.
Bit of a bummer as all the bearings etc. are in really good order
Click to expand...
A few questions if you don't mind.

If not a stopper, what does it do?

Is it a close fit on the forestay?

If you're scrapping the system, any chance I could have the 'stopper'? (I'll gladly pay the postage, and something for it if you wish)
 
parsifal said:
A few questions if you don't mind.

If not a stopper, what does it do?

Is it a close fit on the forestay?

If you're scrapping the system, any chance I could have the 'stopper'? (I'll gladly pay the postage, and something for it if you wish)
Click to expand...

looks nice and stops critters getting into the top of the foil
 
I know that I am late to the party but I am taking one off Swift as it's got a number of issues, starting with it doesn't want to come apart! and its easier to fit a new furler. If it's useful for spares and you can collect from Fareham before Tuesday 14th June, then PM me.
 
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