Mainsheet length....

[prv]

Don't! I can think of anything more useless than a 1m length of rope

But if he buys the 20m and leaves it that length, then as Jac says, he can freshen the nip after a few years by cutting it shorter.

Where it did make sense to buy overlength was on the 2.5mm arctic mains flex I was ordering last night for a new shore power cable. 97p per meter for 50m or more, £1.60 for any less. So 50m cost just under fifty quid, but 40 metres (the amount I actually wanted) would have cost fourteen pounds more!

New extension lead for the garden in the offing, I think

(Not going to just add the extra onto the end of the boat cable, as it starts to get a bit iffy on voltage drop assuming I have everything on at once.)

Pete

 

[onesea]

Yep I agree with the maths.

Don't buy rope thats too large for the blocks ... dont ask

What you do then is turn it onto your "new" jib sheets and but a smaller pain sheet...

So you are thinking of getting 20m?

Don't! I can think of anything more useless than a 1m length of rope, so if you buy 25m you will have a handy offcut.

The problem then is you end up with lots of 5m lengths of rope, to long to throw away to short to keep

I took the old sheet in and said I want one of these, but I guess you do not have that option...

 

[Fantasie 19]

What you do then is turn it onto your "new" jib sheets and but a smaller pain sheet...


The problem then is you end up with lots of 5m lengths of rope, to long to throw away to short to keep

I took the old sheet in and said I want one of these, but I guess you do not have that option...

Chaps - you're brilliant - never expected too get as much fun from a boring question as this..

Too answer this & the other (perfectly valid) question - I don't have one at the moment - I'm making from new, so nothing to compare too/measure..

Lakey - absolutely correct with the Fantasie (swept back spreaders), but I'm setting up a Hurley 20 - not quite so spread back, and 90' makes for an easier "mathematification"... (the one in your picture was moored in the Emsworth Channel up to the year before last, b.t.w - didn't see her last year)

I'm launching a week Friday and won't have time to get down with some string..

I do have a mate with a Hurley though and he tells me his 4:1 is 14 mtrs (!)

I'm going to go 18m...

 

[Greenheart]

Just realised, after several weeks of ownership, that my Osprey doesn't have a mainsheet! Probably looted for the seller's newer boat.

The blocks are all a bit blooming petite for my taste in mainsheet diameters...

View attachment 30411

...is there an easy way to switch that tiny block on the swivel, for something bigger? Does it just unscrew from the sprung base?

I don't much like the prospects for leverage, with the mainsheet blocks barely five foot from the mast...okay, it's four-to-one, but the sail is 100'sq...

...would the leverage be better, with a 3:1 line rigged up to a transom-mounted traveller, led forward along the boom to the swivel?

I'd probably end up with a fifty-foot mainsheet...

 

[William_H]

Back to the OP. I agree as said that with end of boom sheeting 4 to 1 purchase may be too much. I would try 2 to 1. I have a 21fter with large mainsail and mid boom sheeting 4 to 1 is right there but end of boom sheeting will add twice as much leverage.
Also as said an SS wire strop from boom down to top block will save some rope. Not just at purchase but also when sheeted in less rope under feet.
Can't help dancrane I would suspect that the block is mounted on a swivel all riveted into place. You should be able to dismantle enough to confirm. You may have to resort to destructive dismantling then figure out a way to attach a bigger block. Certainly the small block looks too small for a decent sized rope. 100mm min I would think is needed. good luck olewill

 

[johnphilip]

Add a strop between the boom & top block will reduce the o/all sheet length

And provide a guarantee of head injury.

 

[Lakesailor]

If you undo the cross-headed screws that plate will lift off and you may see a nice nut to undo underneath it. I can't see why the block is too small. As long as the mainsheet runs through it it should be OK.
It's not taking the the full pull of the boom , surely it's just to lead the sheet from the traveller into the cleat? Hardly any force there.

You're doing it again Dan. Trying to solve a problem you haven't yet identified.
Take it sailing as it's set up. You may see all kinds of reasons it's like that.

 

[VicS]

Just realised, after several weeks of ownership, that my Osprey doesn't have a mainsheet! Probably looted for the seller's newer boat.

The blocks are all a bit blooming petite for my taste in mainsheet diameters...



...is there an easy way to switch that tiny block on the swivel, for something bigger? Does it just unscrew from the sprung base?

I don't much like the prospects for leverage, with the mainsheet blocks barely five foot from the mast...okay, it's four-to-one, but the sail is 100'sq...

...would the leverage be better, with a 3:1 line rigged up to a transom-mounted traveller, led forward along the boom to the swivel?

I'd probably end up with a fifty-foot mainsheet...

That block looks new..the red plastic is not faded like the bits on the jammer. If its been recently fitted it can be changed I would think.


Looks a tad small and will limit the size of sheet that can be used ... but if it is OK from that point of view do as LS says. Leave it for now and see how it goes. Change it it proves to be necessary.

 

[Fantasie 19]

That block looks new..the red plastic is not faded like the bits on the jammer. If its been recently fitted it can be changed I would think.


Looks a tad small and will limit the size of sheet that can be used ... but if it is OK from that point of view do as LS says. Leave it for now and see how it goes. Change it it proves to be necessary.

+1

Having come to a boat with no mainsheet it never fails to maze me how much blocks cost - altogether the mainsheet for this boat will be just shy of a £100 (£80 for two Selden blocks/£20 for the rope....) so if you can get away with using the existing you'll save a parcel of money for other things you may well need.....

W.r.t. the question about 4:1 v's 2:1 I was guided by two thoughts.... I had 4:1 on the old boat (a 19' er) and it seemed to be about right, but more importantly I also use the mainsheet for lowering/raising the mast so 4:1 can be very useful.....

 

[Lakesailor]

Pop over to http://www.ybw.com/forums/showthrea...RTH-OFFSET-COMPANIONWAY&p=4117822#post4117822 and tell him about costs.

 

[Stork_III]

If you undo the cross-headed screws that plate will lift off and you may see a nice nut to undo underneath it. I can't see why the block is too small. As long as the mainsheet runs through it it should be OK.
It's not taking the the full pull of the boom , surely it's just to lead the sheet from the traveller into the cleat? Hardly any force there.

You're doing it again Dan. Trying to solve a problem you haven't yet identified.
Take it sailing as it's set up. You may see all kinds of reasons it's like that.[/QUOTE

Push the spring down there should be a Clevis pin in there.

 

[Greenheart]

Thanks for these tips and thoughts, everyone.

For myself, I've no doubt I could sheet the main with the (absent) 8mm or 10mm line which the existing blocks permit...but whereas some payments are grudged and feel unjustified, I'd relish shelling out on big blocks and a luxuriously soft braid-on-braid...and since the mainsheet needs replacing, the option to upgrade the fittings weighs pleasantly on my mind...

...as does the option (though it would need much rearrangement) to mount the traveller on the transom, to benefit from the much better leverage there...

...but I probably won't, it's way too much hassle...and if I ever get to trapeze whilst singlehanding (I've read plenty of accounts of Ospreys sailed that way), I'll want the transom area clear of lines, so I can swing the two-meter tiller extension during tacks...

And you're quite right, Lakesailor: the tiny 'sprung' block on the swivel is only a guide, from the final block taking strain from the boom. It's just a pity it restricts any diameter over 8mm...

 

[Fantasie 19]

Pop over to http://www.ybw.com/forums/showthrea...RTH-OFFSET-COMPANIONWAY&p=4117822#post4117822 and tell him about costs.

I know - it's a drop in the ocean really - I'm moaning about having to spend what most people don't blink an eye at when filling the tanks on their Sunseeker...

I admire the Matilda guys spirit though..... if I'd been willing to wait of course, then everything comes down in price as you have the time to hunt around for bargains, go to jumbles, scour ebay, etcetcetc... I couldn't be bothered as I wanted to go sailing..... that's my choice and the kids can go hungry this month.....

 

[Greenheart]

Are there any serious downsides to using lengths of steel wire to join the blocks to the boom? As it is, 3 meters of mainsheet must be in use, even when close-hauled.

 

[Lakesailor]

Please.

Just rig it and go sailing. Everything will become clear.

 

[William_H]

Are there any serious downsides to using lengths of steel wire to join the blocks to the boom? As it is, 3 meters of mainsheet must be in use, even when close-hauled.

It has been suggested that the blocks will hit you on the head. II have had 2 single blocks hanging from my boom (21fter) on a strop about 25cms long. This is just at the entrance hatch. The traveller sheet track is on the bridge deck. No one has ever been hit on the head by the blocks. I have had people being caught or hit by the rope of the mainsheet in a gybe but none hit by the blocks.
Regarding cost of blocks. Being a long tern owner 32 years now same boat heavy usage. I have had a lot of blocks fail due to sun deterioration of the plastic sheave wheel. These are usually rivetted into the ss body of the block. I have ground out the pin on most of them and replaced this with a bit of 6mm od ss tubing with a 4mm screw and nut. Or sometimes a clevis pin. I am still appalled at the price of replacement sheave wheels. good luck olewill

 

[Greenheart]

Please. Just rig it and go sailing. Everything will become clear.

I know, I know...but waiting for the season to start is like waiting for Christmas, aged nine. And it's so cold, I can't even do some serious preparation/fixing up.