Mainsheet blocks

Jan 22, 2008
16
Catalina 275 15 Bellevue, WA
Has anyone documented how to best rig the blocks for the continuous mainsheet?

I bought my boat used and when it was shipped from Michigan, I think they rigged the mainsheet wrong. It always seems twisted. Today I remove the blocks from the boom and tried to roll them some to correct the issue, but I dont think I made it better. Does anyone also know the path that the sheet should follow..and to the extent I want to change it, how would i go about doing that?

Thanks,

Mike
 

Joe

.
Jun 1, 2004
8,198
Catalina 27 Mission Bay, San Diego
Has anyone documented how to best rig the blocks for the continuous mainsheet?
It always seems twisted.
Mike, I don't have any advice specific to your boat, but I can make the suggestion that you lock the shackle posts on the block to keep them from swiveling. It may or may not mean unraveling the sheet, you'll have to take a close look to see what kind of mechanism the blocks use. Some blocks just have a sliding tab, others require removing and reinserting the post.
Running the lines back and forth in the multi purchase rig creates a natural twisting force because of the lay of the rope. Fixing the blocks so they can't swivel will solve the twist.

As far a continuous mainsheet... try working out the ergonomics first, before you start moving things or buying more equipment. Ask yourself how your sail handling will be improved. MId boom sheeting, a dodger, a poorly designed traveler system are all reasons to reconsider the layout. How you like to sail is the most important consideration. Good luck.
 
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Likes: Ward H
Jun 6, 2016
206
Catalina 275 Wilmette, IL
With the mainsheet blocks directed aft (helmsman aft of the track), have the single block (oriented beam/beam) on the aft boom connection and the double block (oriented fore/aft) on the fore boom connection:

P1030697.JPG


Probably easiest to run half the mainsheet through the single block. Then take both ends and run them through the double fiddle (term?) up to the aft side of the double block, through the double block towards the bow and back through the mainsheet block towards the cleats:

P1020691.JPG


Hope this helps.
 
Sep 24, 2018
3,414
Catalina 30 MKIII Chicago
I'm not sure if this is applicable for multiblock setups but when only using two blocks, you want the lower one to swivel but the upper one to not swivel
 
Feb 22, 2015
15
Catalina 30 Redondo Beach
I had that problem on a different boat. Two single blocks. Drove me nuts. Turned out to be tightening the lock screws on the blocks. Had never noticed them.
As Joe said, rig a way to keep blocks on the shackle posts from turning.
If that picture is of your blocks and no lock screws, you might try running a line connecting the blocks center holes. Might be enough to stop the twist. Of course the lock screw is a better approach.