Headknocker on a dinghy

I have this funky little South African scow that I keep on the beach for messing around.

It has a fairly low boom and a long trunk so the centreboard can move to balance the boat for sloop or mono rig sailing. Unfortunately this leaves the mainsheet rigging fairly aft and makes the the slot you pass thru a challenge with the tiller/stick easily getting hung up on the mainsheet. The simple solution is just to play the sheet off the boom but  I have a headknocker for my SanJuan 21 so I gave it a test run on the Sonnet. Takes some getting use to but solves the transition issues. 

Potential issues with this setup? Do other classes do this?




Super Anarchist
East Coast OZ
Not familiar with the term, but it looks like a cleat that swivels from side to side.

For most boats the practical problem is they can only be cleated and uncleated from a narrow range of fore and aft positions.

Too far forward you can't uncleat it. Too far back it won't cleat.

That won't suit most dinghies which require a wide range of movement.

Mind you, many boats sail with a main played from the boom (most skiffs) without a cleat.



Super Anarchist
NA westcoast
Yahh, sailing is a verb, especially for the mainsheet.   Cleats just get in the way. Modernize the sheeting with a bit more purchase, sort a more powerful vang,  and you can lose the headknocker and kneebanger all at once.


duncan (the other one)

Super Anarchist
Yeh - get rid of the cleat - use a ratchet block hung from the boom.

Use 2:1 at the rear end (block on bridle, terminate on boom) for more purchase if you need it.

Other alternative is just to whack a bunch of purchases mid boom to the aft end of the case, and swing your tiller extension out back when tacking.

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As above, if you’re cleating the main you’re not playing the main enough.

I have used a ratchet block on the boom and it works well. My boat is Una rig and possible to over sheet in medium conditions. I did use calibration marks on the sheet. Less of an issue on sloop rig. I think you would benefit from an extra purchase, a block on the bridle and lead the and lead the tale to the boom



Super Anarchist
The biggest problem with a head knocker on a dinghy is that you lose the ability to easily adjust leech tension with the sheet, as you’re primarily just pulling the boom athwartships with no downward force component if you’re hiking at all.  This necessitates very active use of the vang.   Long story short, a headknocker on a dinghy is as much a traveller as it is a main sheet.  



New member
I've sailed Sonnets. They are great boats in strong breeze. Playing the sheet off the boom is not really done and will only work in light stuff. The cleat you've put on the boom may seem convenient but it's going to take your head off if you catch it on a gybe. As Tink said get a ratchet block I would change out the fairlead on the Center board case for a swiveling ratchet block and double up on the bridle end for extra purchase. 

Fold the tiller backward while tacking. 



Right now
Western Canada
Quite a collection you have there, Wannabe. Seems to me I have seen you describe your Solo, Sonnet, 505, FD and SJ21 over the past few years. Is that your SeaSpray in the background, too? 



Lottsa people don’t know I’m famous
Austin Texas
Lots of Ensemble GM sailors swear by their Oxen Block. 
it is a big ratchet they hang from the boom.

on the first pull it locks and holds the mainsheet almost as well as a cleat 

a second pull releases the ratchet and it becomes a free wheeling pulley.

when the sheet is trimmed again it becomes a ratchet 

it takes a bit of time to get used to it because you must always trim a bit to let  the sail out 

( personal experience —— I damn near sunk an Ensign in a round robin team championship because I was slow to get the boom out in a sudden puff. One of my crew spent most of the rest of the race throwing buckets of water over the side ..... but we won... so it came out fine and left us with a better story)

you can probably find a vendor through the Ensign Class website 


Major Tom

Super Anarchist
Darkest Africa
The boom has also been raised 100mm in the last couple of years, and the centreboard has been lengthened, it is now protrudes a maximum of825mm below the keelson, your boat is probably 35 years old.

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This post was a bit of a conversation starter on benefits and drawbacks of off the boom sheeting and the option of cleating. I've tried  double ratchet blocks on the mainsheet but went back to 2:1 and a single ratchet as it felt smoother. The headknocker is positioned far enough forward that it takes effort to cleat and uncleats as soon as you pull on it.


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