How far could my main go over with any value?

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pcatterall

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As my 'new' dinghy's mast is unstayed the boom has nothing to obstruct it. I'm just about to cut the mainsheet in order to keep excess line from the boat. I wonder especially in dinghy sailing how far round the boom should /could go in order to be of any use!
 
Depends if you want to depower on a dead run . Quite useful when surfing downwind ashore. More often you can even stay on the same tack whilst running by the Lee and avoid a gybe if your boom is not prevented from rotating forward by a shroud..

Laser sailors will sail set with reverse flow over the sail . Typically with the boom in excess of 45 degree fore of abeam!

Better looking at it than for it!
 
I think, though I don't know the details, that a sail will extract more power from the wind if the air is moving across the sail than if the sail is at right angle to the wind and the air stalls. I certainly found this to be true with a spinnaker, and I think that dinghy sailors do the same with the main, hence the Laser tricks.
 
pcatterall said:
Thanks, there is quite a bit of 'spare' sheet to allow the boom to go beyond 90 degrees to the boat. I will keep it all for the time being then and see if there are any tricks!
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On a windy day might be worth putting a figure of eight knot to stop the boom going beyond about 80 degrees, and only untieing if expect to need to ease the sail further coming ashore.
Inexperienced Laser sailors used to regularly let the boom out too far downwind and suddenly flip in to windward due to reverse heel from the sail. Very wet. (Clearly experienced Laser sailors choose to do that intentionally, but they have already been through the swim stage and learnt)
 
I bought the recommended length of sheet for my Laser from Mr Cockerill (Rooster Sailing). There is an awful lot of it. I expect you have a bigger cockpit to store it in. I found there was so much sheet I ended up with my feet lashed together. I reckon the end of the boom would go a metre forwards? I don't think I've used that except on the slipway in an onshore breeze. The top laser sailors do push things a long way, especially in waves, to get around other boats in a big fleet. Not relevant to us club sailors?
 
When I used to sail international OK we would often have the boom forward of mast down wind, very tippy though but fast. So needed long main sheet
 
dunedin said:
On a windy day might be worth putting a figure of eight knot to stop the boom going beyond about 80 degrees, and only untieing if expect to need to ease the sail further coming ashore.
Inexperienced Laser sailors used to regularly let the boom out too far downwind and suddenly flip in to windward due to reverse heel from the sail. Very wet. (Clearly experienced Laser sailors choose to do that intentionally, but they have already been through the swim stage and learnt)
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This gave me a good laugh as I remembered sailing Toppers, Lasers, a friend's Europe and my old Finns.

The 90 degrees angle works OK in light conditions but I'd suggest you put a knot into your mainsheet to prevent it going past 80 degrees on a windy day. Anything further will send you straight in for a swim (and I've been there many times).

If you let your boom out to 80 degrees on a windy day the leech of your sail will go further than the boom, and the laminar flow across the sail effectively drives the rig sideways, pushing the boat over to windward. To reduce this tendency you can tighten the kicker but you can over tighten it, cutting off the flow across your sail and slowing the boat.

You sometimes see pictures of singlehanders with unstayed rigs going downwind with the boat leaned over to windward and the boom right out. This is for experienced racers only because if they get it wrong they're going for a swim.

So use a knot in your mainsheet, don't cut the sheet.
 
pcatterall said:
Thanks all! I see that there is enough sheet for the boom to up to the forestay ( except there isn't one!) ! but I will tie a bloody big knot at 80 degrees! I aim to stay in the boat!
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Dinghy sailing? Don't worry about it. I've taken many swims from different dinghies over the years and its also good practice for resolving issues if something goes wrong with the boat. Besides, in Spain the water is warm enough to be inviting :)
 
langstonelayabout said:
Dinghy sailing? Don't worry about it. I've taken many swims from different dinghies over the years and its also good practice for resolving issues if something goes wrong with the boat. Besides, in Spain the water is warm enough to be inviting :)
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Sorry! dinghy here in the frozen north! I do expect a ducking but plan to avoid it if possible! I'm 78 and concerned even in summer about shock. I will wear my shorty wet suit though so probably not an issue.
 
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