Sigma rig setups?

   Just incase to follow up. Dried the boat out yesterday scrubbed her off. Put more tension on the caps, worked on using the runners she how high she'd go before the speed really fell off. Got some odd backstay settings from a book using a fair ammount of backastay in the light stuff. Anyway got a 3rd last night, the best results we've had round the cans at are club. 

Cheers for the help. 

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3793 Send Private Message Find Member's Posts Newbie Joined: 19 Nov 06 Location: United Kingdom Online Status: Offline Posts: 9	Post Options Post Reply Quote 3793 Report Post Quote Reply Topic: Sigma rig setups? Posted: 15 Jun 07 at 9:37am
	Just incase to follow up. Dried the boat out yesterday scrubbed her off. Put more tension on the caps, worked on using the runners she how high she'd go before the speed really fell off. Got some odd backstay settings from a book using a fair ammount of backastay in the light stuff. Anyway got a 3rd last night, the best results we've had round the cans at are club. Cheers for the help.

Stefan Lloyd Send Private Message Find Member's Posts Really should get out more Joined: 03 Aug 04 Online Status: Offline Posts: 1599	Post Options Post Reply Quote Stefan Lloyd Report Post Quote Reply Posted: 13 Jun 07 at 1:36pm
	I've spent a lot of time helming 38 foot cruiser-racers and target boatspeed in powered up conditions was 6.7-6.8 knots. These are slightly quicker boats than a Sigma/36. So yes, I'd try more forestay tension and more pointing.

3793 Send Private Message Find Member's Posts Newbie Joined: 19 Nov 06 Location: United Kingdom Online Status: Offline Posts: 9	Post Options Post Reply Quote 3793 Report Post Quote Reply Posted: 13 Jun 07 at 12:21pm
	At falmouth week last year. We were hitting 7.4 upwind and were holding 8 kts off the wind and getting over 9 at times. The instruments had been califbrated or at least checked over at the begging of 2006. So what you are saying is 7.4 means we are pointing too low. We need to go for more hight? I.e, increased forestay tension using the runners. The boat dosn't have a VMG meter on it, just wind angle and a couple of displays wind, speed, ect. Cheers.

Stefan Lloyd Send Private Message Find Member's Posts Really should get out more Joined: 03 Aug 04 Online Status: Offline Posts: 1599	Post Options Post Reply Quote Stefan Lloyd Report Post Quote Reply Posted: 13 Jun 07 at 12:07pm
	I don't know how well your instruments are calibrated but 7.4 knots upwind, if accurate, is "too fast". For optimum VMG on a boat that size something like 6.5-6.8 would be typical once the boat is powered up. Downwind you aren't likely to get the same speeds inshore because the waves are smaller.

3793 Send Private Message Find Member's Posts Newbie Joined: 19 Nov 06 Location: United Kingdom Online Status: Offline Posts: 9	Post Options Post Reply Quote 3793 Report Post Quote Reply Posted: 13 Jun 07 at 10:29am
	Yeah I realised my mistake about the runners! Read a useful book last night! The problem is before we've only really raced her offshore. So we had the chance to sit there and mess about and in a straight line the Sigma is fast and we got some good results. Started really racing her around the can's this year and just can't get the speeds we've seen out of her. On an upwind leg in say 20kts she used to get about 7.4kts and downwind/ broadreaching anyway over 8. She feels really tender on helm screwing up into the wind alot which she never used to do, in gusts she used to be really steady. As for sails, she has a brand new UK TD Carbon main on her and new set of spinnakers the Genoa all Sobstad gensis. Apart from the No1 which is the hardest used they are all in pretty good condition. I just can't think of anything diffrent apart from the rig and its my weakest point, I've never really got into learning about setting it up. From sailing One Design dinghys I've always had referance points and people to talk to. As I was saying the book I've been reading has given me some ideas to try out, I think its just a case of spending as much time as possible trying new things out. Cheers for any help!

Stefan Lloyd Send Private Message Find Member's Posts Really should get out more Joined: 03 Aug 04 Online Status: Offline Posts: 1599	Post Options Post Reply Quote Stefan Lloyd Report Post Quote Reply Posted: 12 Jun 07 at 8:07pm
	So are you asking about the fractional version? In that case, no the runners aren't for tuning the main. They are for tuning forestay tension (basically more tension = less power but better pointing). On a masthead boat, runners tune mast bend. Runners on = straight mast, more power, runners off = bent mast. On a fractional rig checkstays do the same thing if you have them, which a Sigma/36 doesn't. You want the amount of rake that gives the desired amount of weather helm at the target powered-up angle of heel. Which is all very well if you know either of those targets but you probably don't. Around 50cms of rake is likely to be roughly correct (measured by hanging a weight from the main halyard and measuring the horizontal offset at gooseneck level). When you say "Im not getting the performance I've seen previously" try to be more specific. Slower? In what conditions? Or not pointing? Other reason for going slower are bottom in bad condition, or it's time to write the sailmaker a large cheque.

3793 Send Private Message Find Member's Posts Newbie Joined: 19 Nov 06 Location: United Kingdom Online Status: Offline Posts: 9	Post Options Post Reply Quote 3793 Report Post Quote Reply Posted: 12 Jun 07 at 5:18pm
	Okay. Sigma 362 is the masthead version the orignal 36 is the fractional version. I've been told to get the caps pretty tight but I have no idea how much rake I want on the rig. Im also intrested in how you use the runners, I know they are for tuning the main and don't support the rig, a friend has a suggested to mark these up, which is great but Im not sure what Im looking for here. I think the main problems are Im used to getting settings off sheets and just going with those and playing aroudn with it. With the Sigma I have no refrences or anything so Im struggling to get started. In previous years the rig has been set up by local riggers but Im unhappy with it now and Im not getting the performance I've seen previously. I think it would be worth my while to sit down and sort it out myself to get better results than they can.

TimC Send Private Message Find Member's Posts Visit Member's Homepage Posting king Joined: 18 Oct 06 Location: United Kingdom Online Status: Offline Posts: 153	Post Options Post Reply Quote TimC Report Post Quote Reply Posted: 12 Jun 07 at 2:21pm
	To be honest I've only sailed the 38 so I'm pretty used to its rig but the only 36 we have at our marina is masthead rigged. A quick google search shows loads of pics of fractional 36s so I guess the one I've seen must have a custom rig on it.
	J92s GBR 9224R "Upstart" twitter.com/upstart_racing

Stefan Lloyd Send Private Message Find Member's Posts Really should get out more Joined: 03 Aug 04 Online Status: Offline Posts: 1599	Post Options Post Reply Quote Stefan Lloyd Report Post Quote Reply Posted: 12 Jun 07 at 2:15pm
	Sigma/38 is fractional swept-back rig with runners used to tune forestay tension. It's a lot of years since I sailed a Sigma/36 but from what I remember they are the same.

TimC Send Private Message Find Member's Posts Visit Member's Homepage Posting king Joined: 18 Oct 06 Location: United Kingdom Online Status: Offline Posts: 153	Post Options Post Reply Quote TimC Report Post Quote Reply Posted: 12 Jun 07 at 1:26pm
	Isn't the sigma 36 rig very different to a 38? In that one is very fractional with runners and the much less so? Edited by TimC
	J92s GBR 9224R "Upstart" twitter.com/upstart_racing