Mainsail Centre Sheeting

 

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The 200 is way easier to roll tack than the Fireball ...

Rick

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Rick -  I generally agree with most of what you say but then you usually don't just make statements with no reasoning!

I didn't say RS200s didn't roll well, but I still say they require a quite refined technique whereas in comparison, the Fireball doesn't.

Originally posted by Stefan Lloyd Originally posted by Guest#260 Originally posted by Stefan Lloyd Originally posted by Guest#260 Actually, the hull shape of the 12 & the Merlin are pretty poor for roll tacking as they tend to scoop water over the side as they are so wide. Well it needs fine judgement on exactly how far you can heel, but the width gives you lovely leverage for a good vigourous roll. Believe me, you can propel a Merlin very nicely up the beat by roll-tacking. Agreed ... but round boats roll better ... But if you look at the bit of a Merlin or N12 hull that is in the water, it is quite round. Remember they are wide at deck level but much narrower at the waterline.

I hesitate to get involved in this but I was in Winders the other day and was suprised at just how flat the underwater section of their Merlin is. It still rolls well though - partly because although flat its so narrow that there's little resistance to rolling it. The Merlin rig is near perfect for rolling as well - its light weight mean body movements easily initiate and finish the manouvre whilst the large roach seems to open as air accelerates off it and then close to maintain flow.

The point that all boats are different and require different techniques is  most valid. Compare  for instance an RS200 and a Fireball, to look at them you'd think that the RS with its roundish sections would be a dream to roll tack but the Fireball with its flat panels wouldn't be. In fact, the RS takes a lot of technique to roll well - as it  easily scoops water, and its fully battened main has to be 'popped' at the right moment for the roll to be effective. The Fireball however rolls really well, doesn't readily scoop water (wide side tanks help here) and the main flops over well with little problem popping the top batten.

Edited by Hector

Originally posted by Guest#260 Being able to roll through a large angle means you can do a more effective (illegal) roll tack.

I don't think I'd regard it as the prime chractareistic of a good roll tacking boat. Both my last Cherub and my IC can readily be heeled to very great angles, but neither is precisely a demon roll tacker. Indeed I'd had the Cherub 14 years before we really got roll tacking to work at all, whereas earlier shapes, especially 60s ones, roll tacked just fine thankyou.

I'd regard rocker, reasonable rise of floor and having the buoyancy reasonably near the middle of the boat as being attributes. It seems to me to be all about how the board goes through the water and the water flows round the hull a bit. Flat wedge shaped boats tend just to go splat/splat than gain much propulsion, and boats that are reluctant to tack anyway aren't going to be a good bet, because you lose too much forving them through the tack anyway.

Originally posted by Stefan Lloyd Originally posted by Guest#260 Originally posted by Stefan Lloyd Originally posted by Guest#260 Actually, the hull shape of the 12 & the Merlin are pretty poor for roll tacking as they tend to scoop water over the side as they are so wide. Well it needs fine judgement on exactly how far you can heel, but the width gives you lovely leverage for a good vigourous roll. Believe me, you can propel a Merlin very nicely up the beat by roll-tacking. Agreed ... but round boats roll better ... But if you look at the bit of a Merlin or N12 hull that is in the water, it is quite round. Remember they are wide at deck level but much narrower at the waterline.

True, but you can heel an Ent to perhaps 60 degrees before you scoop any water but you could never do that in a 12 or MR. Being able to roll through a large angle means you can do a more effective (illegal) roll tack.

Edited by Guest#260

Originally posted by Guest#260 Originally posted by Stefan Lloyd Originally posted by Guest#260 Actually, the hull shape of the 12 & the Merlin are pretty poor for roll tacking as they tend to scoop water over the side as they are so wide. Well it needs fine judgement on exactly how far you can heel, but the width gives you lovely leverage for a good vigourous roll. Believe me, you can propel a Merlin very nicely up the beat by roll-tacking. Agreed ... but round boats roll better ...

But if you look at the bit of a Merlin or N12 hull that is in the water, it is quite round. Remember they are wide at deck level but much narrower at the waterline.