I have been using the original 8 mm ropes for the main and jib and today i came accross this page, where they state, that for a 31 ft (as our current boat) a 10 and 12 mm recommended.

I had no issues with the 8 mm so far, but I am not racing, nor I take her out in rough weather.

what size ropes you use on your boat and did you have any issues with a different size before?

12 on the main, 8 on the traveller, 10 on the heady & poled headsail sheets. We were on 12's but works just as well on 10's, although when it gets up around 20-30 it needs 4 wraps to stop slipping. Mine are non tailing old school Barlows with a 150% #1 and 135% #2 headsails.

Can't remember exactly my rope sizes (timber hull, gaff rigged, 30ft) but certainly nothing as small as 8mm. I think 14mm main sheet and 12mm elsewhere. I recommend getting whatever suits the hand size of you and your crew. When you need to haul on a sheet or a halyard it needs to be comfortable and therefore safe.

I replaced my 12mm main sheet with 10mm and the ease of use because of the reduced friction( I guess) was gobb smacking, that being said its only 23m2 ish sail with a 4:1 purchase

Strength-wise you'll be fine with 8m, just comes down to ease of handling and what your winches are geared towards. Headsail sheets that you're handling all the time are nicer if a bit thicker, means less blisters.

Select to expand quote

Dexport said..
Strength-wise you'll be fine with 8m, just comes down to ease of handling and what your winches are geared towards. Headsail sheets that you're handling all the time are nicer if a bit thicker, means less blisters.

blisters are never an issue, always use gloves. I think the 8s slide easier through the fittings. I wonder if that extra thickness helps a bit with longevity

Select to expand quote

woko said..
I replaced my 12mm main sheet with 10mm and the ease of use because of the reduced friction( I guess) was gobb smacking, that being said its only 23m2 ish sail with a 4:1 purchase

thats what i was thinking. less clearance more friction for the rope to slide through

On my 28 most halyards are 8mm spectra, spinnaker halyards 10mm db, spinnaker sheet 8mm db, barber hauler 5mm db, Genoa 10mm db, main traveller 8mm db, boom traveller 10mm db, boom uphaul 8mm spectra, main preventer 8mm db, reef line and outhaul 8mm db, cutter halyard 10mm db, sheet 10mm db, running back stays 8mm spectra, back stay adj. 8mm dynema.
It works fine at steady 35 knots.

G'day, as dexport says strength isn't normally an issue with modern ropes it just comes down to handling.
We ran 6mm & 8mm sheets on everything on a Sayer 12m full carbon race boat, no problems just wear gloves...

Select to expand quote

Hort said..
G'day, as dexport says strength isn't normally an issue with modern ropes it just comes down to handling.
We ran 6mm & 8mm sheets on everything on a Sayer 12m full carbon race boat, no problems just wear gloves...

G'day Hort, what boat?
Seabreezy, I run a max of 10mm on a 40'. Smallest sizes are the spinnaker tweakers at 6mm. For your sheets, make sure they''re big enough to hold comfortably and small enough not to foul your self tailor /deck jammers/cleats etc. Too big a sheet on a self tailor will guarantee it pops out when you least want it to.
And always yes to gloves, and make sure they are in good nick. .
A good mate just upgraded from a Benny 40.7 to a H&H 42, on its first/second sail a month ago his hand slipped of the pedestal, and falling he grabbed the mainsheet just as the trimmer was easing. Result was his index finger went into the turning block and took it off clean. They re-attached it, but it failed to graft and they amputated this week.
Easy to do. I didn't quite lock the traveller last Sunday, and even holding tension on it, the dyneema slipped through my old gloves, shredding the gloves and a couple of layers of skin.
Still can't hold a bloody pen.

There is a difference if cruising or racing.
I would not go for the smallest rope if you are only cruising Large enough to hold comfortably is a plus but not big it fouls 12 mm is good on a cruiser for Genoa sheets. I run 10 mm for spinnaker sheets.

Of course the cost of hardware rises exponentially with the size of rope. 10mm and 12mm is good size for me.

Shaggy, the boat was Wasabi
built for & raced in Melbourne to Osaka

Select to expand quote

Hort said..
Shaggy, the boat was Wasabi
built for & raced in Melbourne to Osaka

Cool boat. Melbourne to Osaka....now that would be an achievement.

I was co skipper not the owner. ( all our sailing was 2 handed or solo) It was an interesting project over 2 years. We minimised weight & tried to make as much stuff dual purpose. All rigging & running rigging was reduced right down to near working load limits. All halyards & sheets were double ended, even our anchor line was 8mm spectra already spiced so it could double as emergency halyards. It sounds over the top but payed off with a 40 footer that only weighed 4000kg to start with every gram saved counted.
Anyway we had a lot of light breeze for the 31 day race but up to 60kn 8 to 12 m waves. Nothing broke & we got line honours & second on handicap.

we run 5 mm dynex on main and jib halyard the main halyard goes to original captive wire winch jib halyard is spliced into 3 strand polyester as atail for handaling

Sooooo many cruising boats I get on have way oversized ropes. The "ease of handling" line is mostly in people's heads.
The friction is way worse than the handling.
12mm max on just about any boat under 60ft.
All running rigging is sized for its stretch (or lack of) not breaking strain, eg. A 40ft masthead cruising boat can use 12mm double braid Genoa halyard, loads will never get close to the 3000kg break, but at 1000kg you'll prob see 5% stretch.
Put a 10mm spectra halyard in and you'll see less than 1% stretch.

My Sabre and nearly all Laser sailors use 7mm main sheet which we hang onto all race!!

shaggy - thanks, I have learnt to be careful around ropes/sheets when my mum's finger was taken off by our german sheppard held on a leash.
plus, if you do not realise how much a nylon rope can burn your hand, you are a fool. As my instructor use to say it: wear gloves, you only have one skin and the rope is stronger, that is why you use it..

Twodogs - I do not see the difference between racing and cruising. If a rope handles harder because it jams due it's larger size, why is that better for cruising? I had 12mm on the jib before and it would barely go through anything. Yes, it was easier to hold, but because it was larger, it started to chafe/wear out sooner.

Jackthe - there is only 10c difference between a size 8 and 10 I think and 100kg in strength

rumblefish - I tend to agree, but rather the size, maybe the frequency of swapping it out for a new one matters more?

Select to expand quote

Seebreasy73 said..
shaggy - thanks, I have learnt to be careful around ropes/sheets when my mum's finger was taken off by our german sheppard held on a leash.
plus, if you do not realise how much a nylon rope can burn your hand, you are a fool. As my instructor use to say it: wear gloves, you only have one skin and the rope is stronger, that is why you use it..

Twodogs - I do not see the difference between racing and cruising. If a rope handles harder because it jams due it's larger size, why is that better for cruising? I had 12mm on the jib before and it would barely go through anything. Yes, it was easier to hold, but because it was larger, it started to chafe/wear out sooner.

Jackthe - there is only 10c difference between a size 8 and 10 I think and 100kg in strength

rumblefish - I tend to agree, but rather the size, maybe the frequency of swapping it out for a new one matters more?

Of course you don't want to go oversize where it won't run through pulleys.
You are not so worried about weight on a cruiser. Or getting the extra 10 th of a knot with a bit of extra weight hanging off the clew affecting the shape.

I think 10mm will suffice. But there is a difference between rope nd rope. Where do you get your ropes from, Whittworths?

Select to expand quote

Seebreasy73 said..
I think 10mm will suffice. But there is a difference between rope nd rope. Where do you get your ropes from, Whittworths?

If you're talking double braid, then Whitworths is fine.
Spectra, if you're not exposing the core then the Donaghys stuff from Whitworths is ok, don't like their own Tec brand.
If you're exposing the core you want spectra with a smooth dyneema core, not white fluffy stuff!