Enlarging Bolt Rope Diameter.

Appledore

Appledore

Well-Known Member
Joined
13 Nov 2011
Messages
810
Location
Bodmin Moor, Cornwall
Visit site
I've just bought a furling Genoa on Fleabay, and, as always, there is a risk. However, the sail size is fine for my boat except - as I thought it might be - for the bolt rope diameter. The sail, by the way, appears to be of Swedish make.

The bolt rope is 5mm and attached to the luff by a very stiff type of binding, not just sailcloth. It slides up my foil OK, but it is a little thin, and I would worry that it would be very likely to pull out. I suppose I could always keep a turn of sail on the foil, but that's not really the answer of course.

The only thing I can think of doing is purchasing sufficient adhesive Heavy Duty Sail Repair Tape (as advertised on Fleabay) and wrapping this around the existing bolt rope, extending each side to the width of the tape, i.e 50mm or 20+ mm each side. That should give me a little more thickness over the bolt rope.

The sail was not a lot of money, and it's not going to be worth giving it to a Sailmaker to fit a larger rope.

What sensible ideas have the panel got to suggest please?

Thanks.
 
Not convinced that your idea will work. You are also increasing the thickness on the sail that goes through the slot which might make it difficult to raise or lower.

No better ideas I'm afraid. The thought of it escaping in a blow is a bit alarming!

Could you sew on some webbing loops with sail slugs of the right size?
 
Last edited:
MoodySabre said:
Could you sew on some webbing loops with sail slugs of the right size?
Click to expand...

That thought had occurred to me, but the sail fabric adjacent to the bolt rope is very hard, almost like a plastic laminate (which I'm sure it isn't!). SWIMBO might not appreciate the number of broken sewing machine needles! However, a thought just occurred to me that I could perpaps drill (1mm drill??) through the fabric and affix the said loops using tough sail thread??
 
Is the slot so wide that you can actually pull the rope out if you give the fabric a good yank? Having too thick a luff rope will invariably cause problems, sooner rather than later. My Genoa is 35 square metres and the luff tape is only around 6-7mm in total (rope plus covering tape).

Remember that the force that is trying to pull the sail out of the slot is distributed along the entire length of the luff; it is not localised.
 
MoodySabre said:
You are also increasing the thickness on the sail that goes through the slot which might make it difficult to raise or lower.
Click to expand...

Surely if the slot was already that tight, there'd be no risk of the rope pulling through it and no need for the modification?

Pete
 
PUFF:

The bolt rope on my existing Genoa is about 7 mm. This one is 5mm, and the slot is marginally narrower. I can just ease the bolt rope out from the slot where it feeds into the foil, so it's only a fraction undersize, hence wondering about binding sail repair tape along the full length of the luff. Could add a milimeter or thereabouts.

PETE:

The above should answer the query. Bolt rope internal could be 7-8mm, but slot is probably 4.5mm wide.
 
Friend of ours recently had their bolt rope changed by a sail repair place. Cost £60. (38ft boat.)
They pulled out the old rope whilst replacing it with a larger size.
Straight forward job apparently.
 
Appledore said:
PUFF:

The bolt rope on my existing Genoa is about 7 mm. This one is 5mm, and the slot is marginally narrower. I can just ease the bolt rope out from the slot where it feeds into the foil, so it's only a fraction undersize, hence wondering about binding sail repair tape along the full length of the luff. Could add a milimeter or thereabouts.
Click to expand...


I agree that 5mm rope and a 4.5 slot won't work. The proper way to solve this is to cut off the existing "binding" that you mentioned and replace it with thicker continuous support tape (or "luff tape", as it is sometimes called). This tape can be bought ready-made from a variety of sources. I would suggest a #7 which costs around $4 per foot from here: http://www.sailrite.com/Continuous-Support-Tape-7#description

If you wish to see a whole video (around 45 minutes long) about how it's done you might want to have a look at this: https://www.youtube.com/watch?t=2152&v=8AY9c28aicA

You do need a good sewing machine if the sailcloth itself (and not just the existing "binding") is very heavy - which I doubt. If you have average manual skills you should have no problem; I have done it several times on my and friends' sails.

I hasten to add that I have no connection with the company to which I linked other that I have bought stuff from them in the past. I would suggest that you make approaches to a sailmaker to obtain a ball-park figure of what it would cost so that you can better decide whether to do it yourself or to have it done professionally. I do believe that there are a couple of sailmakers on this forum.

Good luck.
 
prv said:
Surely if the slot was already that tight, there'd be no risk of the rope pulling through it and no need for the modification?

Pete
Click to expand...

The slot is for the thickness of the sail and luff tape/binding - that would be much the same regardless of the bolt rope size. It is just the bolt rope that is too small. Making both thicker is not necessary. I think you have misunderstood.
 
I've just gone through the process of replacing my luff foil. A lot of those on the market are actually 5.5mm and the Selden I went for certainly is. My jib luff tape is 5mm. I expect no issues. I also had a conversation with a surveyor, who suggested it wouldn't be worth it for a mm.

If you do want to replace the luff tape, it cost me £235, IIRC, about 5 years ago for a 16m luff.
 
lpdsn said:
I've just gone through the process of replacing my luff foil. A lot of those on the market are actually 5.5mm and the Selden I went for certainly is. My jib luff tape is 5mm. I expect no issues. I also had a conversation with a surveyor, who suggested it wouldn't be worth it for a mm.

If you do want to replace the luff tape, it cost me £235, IIRC, about 5 years ago for a 16m luff.
Click to expand...

Had a quote from a Plymouth sailmaker today to removing the existing rope and tape and fitting a 7mm one for £11.50 a meter plus VAT. Sail is just over 7 meters, so about £100.
 
You must log in or register to reply here.

Share this page

Top