sunfish mainsheet controls upgrade

I’ve written several posts in the past about upgrading to a Sunfish mainsheet ratchet block and the associated rigging to control your mainsheet.

• sunfish mainsheet block
• sunfish mainsheet block upgrade
• mainsheet block stand-up spring
• harken h150

six years ago, I said the following, and I still believe it to be true:

I really enjoy playing the mainsheet through the ratchet block, and enjoy how the sheave on the ratchet block grips the mainsheet, so that the amount of pull I see is reduced, helping to keep my hands and arms from tiring as quickly.  I also like that this setup will force me to focus more on the sail trim, instead of just using my old setup to set it and then forget it.  I’d highly recommend this upgrade to other Sunfish sailors.

the Harken 2135 ratchet block, in particular, has grooved edges on the inside of the sheave.  these grooves help to “grip” the line and reduce the amount of line pull by a factor of up to 10:1.  so if the sail is pulling with 100 lbs, your hands gripping the mainsheet could see a reduced load, maybe as little as 10 lbs.  over a long day of sailing, this will be significant!

part numbers and such are strewn along between the various blog posts, so I wanted to pull everything together in one place with a nice summary parts list and I made a labeled diagram to show what parts go where.  the picture is from our Minifish, but a similar setup is what I use on my Sunfish as well.

here is the parts list (while most of these parts are available at most Sunfish suppliers, you can find the same part numbers at your preferred or local supplier as well):

• Harken 2135 ratchet block (link)
• a cheaper ratchet block option is the Holt Nautos block, via Intensity Sails (link)
• Harken 150 cam cleat (link)
• Spring Cup HSB2 (link)
• Stand up spring H071 (link) or (this one) or (this one from Intensity Sails)
• Eyestrap, LP91100 or H137 (link)
• Stainless steel fasteners (I use machine screws, with a large flat washer and a nylon locking nut on the interior of the boat)

all told, you’re looking at an upgrade in the $70 to $100 range (depending on which ratchet block you pick).

if your Sunfish was a barn find or a cheap pick off of craigslist, this might be a lot compared to the price of your boat, but trust me: you’ll be happy with the upgrade if your current Sunfish setup only has the old “knee-knocker” hook at the lip of the cockpit.