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  #16  
Old 01-16-2017, 01:10 PM
BertKu BertKu is offline
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Location: South Africa Little Brak River
Could anyone help me with the following.

I made my own roll on / roll back system for my jib.

Question: Do you have 2 ropes to the roll up unit + the rope attached to the jib sail?

OR

Do you have 1 rope to the roll up unit and you unroll the sail by pulling the sail rope.

Much obliged if you could give me some information. Bert
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  #17  
Old 01-18-2017, 12:00 AM
BertKu BertKu is offline
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Quote:
Originally Posted by BertKu View Post
Could anyone help me with the following.

I made my own roll on / roll back system for my jib.

Question: Do you have 2 ropes to the roll up unit + the rope attached to the jib sail?

OR

Do you have 1 rope to the roll up unit and you unroll the sail by pulling the sail rope.

Much obliged if you could give me some information. Bert
Let me re-phrase my question. Would it have an advantage if the roll-on -roll off jib system has 2 ropes and can be independently controlled from pulling the sail. Bert
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  #18  
Old 01-18-2017, 04:39 AM
gggGuest gggGuest is offline
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I don't get involved with such things, so I don't know, but for unrolling the jib to be a bigger load on the sail than the wind provides would seem surprising unless the system had quite horrendous friction..
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  #19  
Old 01-18-2017, 12:07 PM
BertKu BertKu is offline
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Quote:
Originally Posted by gggGuest View Post
I don't get involved with such things, so I don't know, but for unrolling the jib to be a bigger load on the sail than the wind provides would seem surprising unless the system had quite horrendous friction..
Thank you for your reply. You see, I thought maybe somebody who is using a roll-on jib system, maybe could tell me, yes sometimes I wished that I could roll-in and roll-out, without to fiddle with the jib rope. So I have in the meantime modified my top bracket and am able to roll-out by pulling the jib rope. Should I have trouble with the 25 mm rod whereon the sail is wound around, I can either then increase the size to 40 mm diameter or to add a 3rd rope. Thanks gggGuest.
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  #20  
Old 03-04-2017, 07:02 AM
BertKu BertKu is offline
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Location: South Africa Little Brak River
Quote:
Originally Posted by gggGuest View Post
I don't get involved with such things, so I don't know, but for unrolling the jib to be a bigger load on the sail than the wind provides would seem surprising unless the system had quite horrendous friction..
gggGuest. I had no alternative than to modify my reefing system. The sail maker who likes to make the 8 m2 sail, is pulling the sail in at the middle, while a normal jib is from the bottom close to the reefing drum. The result was that the force on the middle of the 25 mm pipe was often too great and the pipe started to bend. Needless to say, that the system was not reliable enough.

Therefore I have split the drum in 2 sections and made it a type of “endless loop”. If I roll the sail out, the rope winds up on the other side. If the sail needs to be reefed in, I bring it back by pulling the other way.
It performs like a dream , it is reliable and I am able to pull the rope from the cockpit. The only disadvantage is that I had to reduce the rope size from 8 mm to 6 mm. To enable to reef the sail in and out.
Cost? I made it for 3 dollar off cut stainless steel from a manufacturer, who otherwise have to sell it at scrap value. A piece of strong plastic pipe, 4 long SS bolts and nuts and 6 small 5 mm SS bolts. I used a lathe to make 2 end parts from a piece of aluminium rod. Thereafter, I did some anodizing on the aluminium end parts. Bought for 2,5 dollar 15 meters of 6 mm rope. I used 2 mm SS welding wire for the guidance of the rope A piece of rubber I still had and the total cost was +/- 10 dollar.
This exclude the anodized aluminium 25 and 22 mm pipes on which the sail roll up.
Bert
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  #21  
Old 03-04-2017, 05:51 PM
CT249 CT249 is offline
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A dinghy class I sail used to have an endless rope. When your (adjustable) rig tension was low the endless rope allowed you to unroll the jib more easily. It also meant that you were not compressing the rolled jib by pulling on the sheet.

A lot of the time the jib was unrolled via the sheet, but there was no cost and some benefit in the endless system.
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  #22  
Old 03-05-2017, 03:11 AM
BertKu BertKu is offline
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Join Date: May 2009
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Location: South Africa Little Brak River
Quote:
Originally Posted by CT249 View Post
A dinghy class I sail used to have an endless rope. When your (adjustable) rig tension was low the endless rope allowed you to unroll the jib more easily. It also meant that you were not compressing the rolled jib by pulling on the sheet.

A lot of the time the jib was unrolled via the sheet, but there was no cost and some benefit in the endless system.
Thank you, I thought already there must be commercial reasons not to offer this kind of roll up/off system. Thanks I am enjoying this system now. Bert
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