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pointing and speed

Started by mattb, 23 Mar 2005, 08:56

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mattb


DavidW

And now for the science!
Matt if you think back to Sunday you'll notice that all the boats in front of you were coloured - your's is white. Clearly satatistical analysis from this sample will reveal that coloured double bottom boats are quicker than white - this is proven further when you think back to Graham & Zoe sailing "Thanks for all the Fish", they were definitely slower when sailing white side up!

Seriously though - there was a lot of video footage taken on the day - Ther may be some clues in that, Graham is the custodian. There were some big shifts, being on the wrong side of some certainly cost us a lot of ground on occassions. We were generally sailing upwind with tell-tales on the jib streaming horizontally on both sides of the sail - I am more used to having the windaward one lifting a bit but we seem to foot much faster for a degree or two less pointing.

If all else fails enjoy the painting!

David






David Wilkins
3481 Cooked to Perfection

Confused (Guest)


Mikey C

Agree in general with what has been said before, only I disagree with the order!

Pointing in general is developed from the overall efficiency of the complete package, not just a particular bit of it.

Flatness for maximum efficiency through the water

foils and underwater area need to be in as good a condition as you can be bothered to make it - water is denser than air by a considerable amount and imperfections will show up here.

As new a sails as you can afford (from a reputable class sailmaker if I remember Mr Ross correctly...)

The measurements in the tuning guide wont help you much if your centreboard is a foot further back... In general try and set the rig up for balance, keep making minor rake adjustments until you can let go of the tiller upwind with the boat flat is the best guide. This makes sure you are not applying too much handbrake...

Video is good!

Cheers

Mike C
N3489 Radical Edward

PS. I agree with David, paintjobs are very important.
Carbon Toys for fast girls and boys!

//www.aardvarkracing.co.uk

Tim L (Guest)

Quite dangerous to make assumptions about pointing when sailing on inland venues as the wind is quite capable of extreme randomness even when you are only a length or two away from the other boat.

How much do you play the kicker as the breeze changes Matt? As your foils are presumably pretty good and your boat has been set up properly it's probably down to those controls that have to be set by feel and eye.  The kicker is key, back few inches of the top batten should be in line with the boom (which should be as close to centreline as you can hold it flat with.  For extra pointing you can hook the batten up a bit if the telltale will stay alive but you have to be very careful of stalling and be ready to dump several inches of kicker if you feel the breeze dropping or the boat slowing.  Have a look at the video and then get someone who does point well to go for a sail with you as they'll probably be able to tell you pretty quickly whether its a handling or setup issue...

T
N349? (It lives! Well as a shell so far...)  

mattb

Thanks for all your input.

In reponse
David - my boat is white - but my sails aren't -does that count?

To Confused - I am very sorry if you feel I have slighted you in any way. I was only asking for some advice and not making any attempt to upset admirals cup sailors. I mention the flooredness of my boat to indicate that its modern and down to weight - both of which might have an impact on speed.  Thanks for the advice anyway. Mainsail leech might well be the problem.

Mike -
If I'm pointing does that mean I've got an efficient rig? Doesn't sound quite right because I should be going faster. I certainly could have been sailing not quite flat because I was a little over powered in the gusts..... Something to work on there. Sails are alverbanks - same as yours I think. The rig balance sounds like a possible cause so I'll try it out this weekend. I'll have to rig something up to indicate when the tiller is centred....Ta.

Tim,
I've noticed a pointing advantage at all the open meetings I've been too over the last year. I guess - from what you say that the leech is too hooked. Actually I usually try to set the kicker so that the tell tales fly upwind. letting it off until they do - but I'll certainly look at the last few inches to the top batten next time.

You point well. Would you like to do a couple of upwind laps with me at Axbridge (assuming I can get there)?

Graham -
can I have a copy of the video please?

Thanks
Matt








Jimmy Whitehead

matt, an easy way to know if the boats flat is to let go of the tiller.....if the boat turns in any direction then your not flat! And if you ease off just a few degres then the boat will get a turn of speed and the apperent wind will move round which basically means you can point higher.

thats my thoughts anyway

Jimmy
N3458
(i think this has few few mistakes on the "english" front in it)

zozzab

Hi Matt, just had a look at the video and have a few observations:
- The rig looked great and your leech looked fine in the windier stuff but a bit hooked in the light stuff, could try letting the kicker off and taking the leech tension on the main sheet when it is light (that's what we do) and then applying kicker when it gets up
- You could do with sailing flatter, particularly when coming out of tacks (and there were plenty of those at Burghfield) to get the boat up to speed. Best options; dump the main more quickly when you get a gust to keep flat, get on the side quicker out of the tack, hike harder. At times we were absolutely fully hiked at Burghfield
- Don't get too hung up on direction that you are pointing relative to other boats, the video shows the effect of the gusts and shifts coming through which can be quite localised.

We don't have a TV / video so can't dump the footage to VHS but can show it to you at Bristol or burn a CD (with as much as I can fit on)

Happy tuning

Graham

MattB (Guest)

excellent.

thanks for taking the time Graham. I know we have problems getting the boat flat out of tacks - partly because its tricky to geet our feet under the toe straps and partly because were not confident enough to fully commit ourselves to the 'from the knees' hiking that you and Zoe do - in puffy and shifty winds.

I am reassured about the leech settings but  I'll let off even more when it goes light.

Selected extracts on a CD would be really good if you can find the time. I'm not sure whether I'll be at axbridge as Paula is away skiing. Does anyone else want to stand in as crew in my slower than it should be N12? All applicants considered!

Cheers all
Matt
N3486

DavidW

Ah! On-line coaching - this is brilliant!
Graham when you next get a spare moment to study the video I'd appreciate your comments on our set up. I wont get too upset about any comments of lack of co-ordination between helm & crew - it was the first time Helen & I have sailed together and probably the first time she'd sailed with someone nearly twice her weight!

Hope to see you at Brsitol - still looking for a crew - and before you say I don't think it will be windy enough ofr Matt and I to sail together!


Cheers

David
David Wilkins
3481 Cooked to Perfection

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