New Blocks for Mainsheet on 45 Footer

[UNCIVILIZED]

Originally Posted by CaptNemoO2

Thanks. I tried to Google this setup but I had a difficult time figuring out what terms to search for. Most of my hits revolved around dinghys. I would like to find out more info, especially to double check the order the line runs through the 3 blocks on the boom, but it's proven to be a hard search! Any hints?

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I'm not 100% clear on what you're asking, but these links may help you sort out your confusion.

Harken - System Diagrams
Harken - Mainsheet Systems
If not, then try & spell out what the problem is, & let us have a crack at it. Also, have a look in their online Product Support Section, there's a LOT of good info there.

[CaptNemoO2]

Originally Posted by UNCIVILIZED

I'm not 100% clear on what you're asking, but these links may help you sort out your confusion.

Harken - System Diagrams
Harken - Mainsheet Systems
If not, then try & spell out what the problem is, & let us have a crack at it. Also, have a look in their online Product Support Section, there's a LOT of good info there.

I've been to Harken's site, it does not show this particular setup. I just figured any mainsheet rigging that dampens the shock loading of a jibe would have more information about it online.

As far as my question about rigging it goes is regarding the order the line is fed through the blocks on the boom. Having never seen this type of mainsheet setup before, I wanted to make sure it's rigged right (see my picture posted earlier). The previous owner had several things rigged wrong, like the vang was up side down. Flipping it back the right way increased it from 4:1 to 5:1.

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[Sailor Bob 350]

If it was me, I'd skip all the math and (in my opinion) under-engineered Harken stuff. I'd get a set of Garhauer blocks, with ball bearings, of the same dimensions (maybe use a double at the bottom if the pull geometry is entirely parallel), and a new main sheet. Better than new.

[daddle]

Even though I like high tech gear in general, I use plain old Sta-Set (dacron double braid) of 11mm (7/16") for the mainsheet. The little bit of stretch saves the gear in a high-wind or accidental gybe situation. Low stretch (Spectra) lines can destroy the blocks, traveller, or track. The bit of stretch does not seem to cause a trim problem as it would in a halyard or guy. The money you save can be spent of nice blocks.

[UNCIVILIZED]

Originally Posted by marinduque

Even though I like high tech gear in general, I use plain old Sta-Set (dacron double braid) of 11mm (7/16") for the mainsheet. The little bit of stretch saves the gear in a high-wind or accidental gybe situation. Low stretch (Spectra) lines can destroy the blocks, traveller, or track. The bit of stretch does not seem to cause a trim problem as it would in a halyard or guy. The money you save can be spent of nice blocks.

On this, you might try Regatta Braid, it has about double the stretch of Sta-Set.

As to main sheets which are set up, or designed to minimize the shock from gibing, I don't know that such exist. Other than going to twin main sheets, & or preventers.
There are, however, several commercially made products designed to slow booms down (mostly when gibing). Boom-brake, I think, is one of them. But they're rigged independently of the mainsheet as far as I know.

Basically, they work on the same principle as a Figure-8 rappel device, only they're a lot bigger & run the line through a few more twists & turns, to increase friction (during a gibe).
Kinda' unnecessary if you ask me, but there are a number to chose from. Or one can go the DIY route, & fabricate something similar.

I say, ust leave a pair of preventers pre-rigged. KISS.

[UNCIVILIZED]

Originally Posted by CaptNemoO2

I've been to Harken's site, it does not show this particular setup. I just figured any mainsheet rigging that dampens the shock loading of a jibe would have more information about it online.

As far as my question about rigging it goes is regarding the order the line is fed through the blocks on the boom. Having never seen this type of mainsheet setup before, I wanted to make sure it's rigged right (see my picture posted earlier). The previous owner had several things rigged wrong, like the vang was up side down. Flipping it back the right way increased it from 4:1 to 5:1.

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On your mainsheet, the most similar one on Harken's page is the 5:1 with a Dedicated Winch.

To rig your system a bit more efficiently: Start @ the pad eye, go over a single block mounted on the middle bail, then down to the upper sheave of the fiddle (double) block. From there, up to the single block on the aft pad eye, & down to the bottom sheave of the fiddle (double) block. Then, up to the single block mounted on the forward pad eye, & over to the deck block on the starboard side.

Can't promise it'll give you much, but what can it hurt to try. Getting rid of one of the singles on the boom, & swapping another for a fiddle with a becket would likely be your best bet (aside from lower friction blocks).

And FYI, it's still safe enough to slow the boom's crossing via the hand on the sheet technique, when the wind's light. Just do a controlled ease of the sheet through your hand, as the sail reaches centerline & starts to refill on the new tack.
I've done it plenty of times on Maxi's in light air. The technique doesn't change appreciably just because the boat/sail is bigger.

[Zach]

It looks like to me, that someone broke the block that went on the boom bail that is currently a bowline.

I bet, that block was a becket block and they reversed the run on the traveler blocks to let it dead end at the boom, instead of running to the boom, to the traveler block, and back to the becket.

Just my .02... Most of the time stuff that doesn't look right, happens because someone jury rigged something, that works well enough that it didn't bother them enough to replace.

Zach

[CaptNemoO2]

Originally Posted by UNCIVILIZED

On your mainsheet, the most similar one on Harken's page is the 5:1 with a Dedicated Winch.

To rig your system a bit more efficiently: Start @ the pad eye, go over a single block mounted on the middle bail, then down to the upper sheave of the fiddle (double) block. From there, up to the single block on the aft pad eye, & down to the bottom sheave of the fiddle (double) block. Then, up to the single block mounted on the forward pad eye, & over to the deck block on the starboard side.

Can't promise it'll give you much, but what can it hurt to try. Getting rid of one of the singles on the boom, & swapping another for a fiddle with a becket would likely be your best bet (aside from lower friction blocks).

And FYI, it's still safe enough to slow the boom's crossing via the hand on the sheet technique, when the wind's light. Just do a controlled ease of the sheet through your hand, as the sail reaches centerline & starts to refill on the new tack.
I've done it plenty of times on Maxi's in light air. The technique doesn't change appreciably just because the boat/sail is bigger.

Thanks, I will try re rigging it the way you suggested. I do plan on replacing the blocks, but I will probably keep the three on the boom to keep the same load distribution. I need to replace them with ones that don't swivel, and would like to go to ball bearing blocks, probably Garhauer.

And for the jibe technique, I know it doesn't change, just bigger forces involved. But I'm more stupid than others so I do it on my dad's boat. On my boat, I'm usually at the helm, and I'm not going to tell a crewmember/guest to do that. I don't want them getting hurt, we're only out there for fun afterall. And we all know it's all fun and games until someone gets hurt...

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