More Blocks On Dory Lug Main Sheet?

The Dory lug kit main sheet is designed with two turning blocks, one on the aft end of the boom, the other one mid boom, the main sheet going from a knot on the bridle to the two blocks and to the skippers hand.  I've seen multiple builders on You Tube videos that have 2 extra inexpensive blocks, one on the bridle and one in the boat..like this...main sheet ties to aft end of boom, down to a block on the bridle, back up to a block on aft end of boom (thus one purchase for half the line tension in the skippers hand) up to a mid-boom block, and down to a block on the daggerboard trunk (or somewhere) so the main sheet has a constant pull angle regardless of boom position.  I'm sure this post will get replies of "overkill" but if anyone has this on their boat, I'd be happy to hear how it works, or other ideas...thanks!


7 replies:

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RE: More Blocks On Dory Lug Main Sheet?

   I don't have a dory, but love sailing small boats - Snipes, 420s, lasers...

I like having a black on the trunk or somewhere in the cockpit to sheet from. But it is just a matter of personal peference. We ussually have a small ratchet block there and no cleat. make sure you put a spring on the block so when it is unloaded it will stand up, as opposed to flopping over and marring your beautiful varnish job. Harken, Ronstan ... all sell small dingy blocks and appropriate springs.

In my Snipe I have the mainsheet rigged as optional two parted from the traveler, even though that is no longer the style in Snipes. I like the extra purchase on the main sheet on windy days due to some tendonitis in my elbow. Again just personal preference. just realize your mainsheet needs to be longer to do this. 

Try it all the different combos and see what you like the best. I would think with a balance lug rig you will not need to generate much down force on the boom for sailing to windward (since the sailis self vanging), and therefore the two part mainsheet off the traveler is propably overkill. But at the cost of two small blocks and an extra long mainsheet, have fun making your own decision!

Joel

RE: More Blocks On Dory Lug Main Sheet?

   My concern would be that as you add blocks, you get more power to control the sail but have to pull further to get the boom to move the same distance.  There is a balance between how hard you have to work vs how many times you have to grab, pull, grab again to move the boom a certain distance.  

I am not explaining well but I hope the idea came across.

Ed

 

RE: More Blocks On Dory Lug Main Sheet?

Ed,   Agree adding purchase adds amount of sheet to pull in (and have laying about when tight sheeted), good point, thanks. 

Joel,I like your idea of having a stand up ratchet block (and no cleat) on the trunk or somewhere in the cockpit to sheet from....that allows the sheet to always be coming from the same location

So I think I'll end up adding the center ratchet block for convienence (which doesnt add purchase), thanks Joel,  and not add the two blocks that add purchase for now, thanks Ed.

Related question-----

There's one other block I forgot to ask y'all about...on the "stock" NE Dory arrangement, the main sheet is tied to a fixed center point on the bridle.  You Tube videos of NE Dorys show a small block on the end of the sheet that can ride across the bridle so the sheeting position is more under the boom.  I guess technically that changes the bridle to a free moving traveler sort of.  I know the nature of the lug rig is self vanging but it still seems like a inexpensive block to travel on the bridle makes sense.  Anyone?

Thanks!

Curt 830/997-8120 [email protected]

 

RE: More Blocks On Dory Lug Main Sheet?

I wondered about this type of question when building my dory.  Decided to sail it first without adding anything additional like the ratchet block mentioned.  Glad I did, and I suggest to anyone doing that first.  I still haven't made any changes.  If I went out on all-day or multi-day tours or trips, I might see things differently. 

RE: More Blocks On Dory Lug Main Sheet?

Curt,

Sounds like you're describing a sheet horse. Small boats work just fine with the sheet tied to a metal (bronze, brass or SS) ring that slides across the horse, instead of a block. That's what I've got on all 3 of my sheet horses.

I like Frank's idea of sticking with what the designer specified at least until you've tried it and decided that you need the change.

Laszlo

RE: More Blocks On Dory Lug Main Sheet?

Laszlo,  I understand, I'm just trying to get things covered before we leave for a 2500 mile drive to Maine for the summer with the boat, especially anything that may require drill fill drill, or mounting a block of wood etc

RE: More Blocks On Dory Lug Main Sheet?

   Curt,

The block on the traveler is used in small boats to keep the boom from centering in the boat. Small single sail boats - sunfish, lasers... do not want the boom on the centerline up wind. the sail will stall and create too much sideways force for the underwater foils to conteract.

Boats with a jib to curve the wind want thier mains on the centerline upwind. Without a jib, The mainsail needs to have the same angle of attack as a jib (never sheeted to the centerline!) so a block riding on a traveler helps keep the main from being over sheeted and stalling. Of course, the mainsheet tied to the center of the traveler also works fine, one just needs to be careful not to 'over sheet' and pull the boom to the centerline. A good rule of thumb is to sheet till the back of the boom is over the corner of the transom. That should give you and angle of attack simular to a jib.

How tightly you can sheet is depended on a lot of factors including the effciency of your underwater foils, hull shape, wind speed, waves...

Joel

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