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Hello, is there any body out there?

Started by RogerBrisley, 31 Aug 2005, 11:27

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RogerBrisley

The recent mast weight discussion has been interesting,  (Yes Anonymous prats should keep away) but apart from some event reporting,  matters have tended to be slow and dull.  Not pointing fingers but where are the stimulating ideas flowing from"ermmm!" jimmy et al ?

There used to be a lot more going on......

I'm relatively new to the class and want to get a design 8 sorted,, so far i do not have any idea about where to start with tuning like how level (and what constitutes level) and whereto go from there.

Help

Roger

Antony (Guest)

Roger,
There is a 21 page downloadable (is that a word now?) tuning guide on this site.  On the front page top right go to 'About' and follow your nose through 'hints, tips etc'.  The tuning guide was extensively re-written recently with a lot of photos showing how to set a boat up as well as a table of numbers to aim for.

Have a go with the guide and make sure the boat is set up about right (spreaders, mast-bend, rake etc), then there is a technique guide that should help with how to sail the boat.. the key is to keep it flat.  

Obviously come back with questions if it does not work or make sense.

Have fun,
Antony

RogerBrisley


Anthony

Thanks for the reply.

I had already downloaded the Tuning guide but what eludes me presently is datum fore and aft trim particularly for a Design 8... i'm  currently obssessing (as my crew describes it) about mast rake.  Do the measurements in the guide refer to measurements taken with the top of the centre board casing being level ie with spirit level?  or does it refer to trim as I sail it and in which case is my normal  trim correct?  In this regard I'm obsessed with not having a rooster tail at the stern and thus trimming down at the bow.

Roger
3334

Roly Mo

Roger

Bring the boat, the guide and a big tape measure to the Ripon SC open (1 October) and we will help you set it up.  Both Howard Chadwick and Philip David make/made Design 8's go fast and I'll ask them if they will help out too.

Bernard
N3447

Antony (Guest)

Roger,
That is quite an obsession you have building there.   I would suggest the following:

1.  Get to Ripon if possible.
2.  Set the rake up using the tip to transom measurements in the guide.  I appreicate the issue with measuring being that all the boats are different, but we used to measure rake on the D8s as being tip (i.e the black band at the top of the mainsail track) to the floor just inside the transom as near the middle as you can get.  Using this measurement you should be able to get the rig right without stress about how level the fore-aft trim is.  Set up the bend/spreaders etc first as they do have some impact on the number.

Fore-aft sailing trim is more subjective.  In a D8 when you are both on thewindward side you just sit next to each other with helms legs aft of the thwart and crew by the shroud.  In lighter airs you can move forward, and on a light run you will want to both sit on opposite sides beside the shroud.  To be honest I would be surprised if you are doing much wrong fore and aft as it is pretty intuitive.

More likely problems upwind include the following:
1.  Keeping the boat as flat as possible, rig upright, and minimises wetted area so is fast if difficult to achieve.
2.  What you are, or are not, doing with the kicker.

Good luck,
Antony

MarkSimpson

Roger, we'll be at Scaling doing race officer duty on sunday.  We could get there early and have a look at things if you like?  Give me a call at home if you're interested.

Cheers
Mark

RogerBrisley

Thanks Anthony. Bernard and Mark for your advice / offers of schooling

Today Mark brought his know how and tension guage,  i brought my new extra long tape measure. to Scaling Dam.  My rig tension was about ok - only slightly soft (though I was off the scale) and rake etc was ok too.  Actually I found the results of measurin the rig tension quite instructive -  how little change in the muscle boxes could result in large changes in rig tension.

The net result of todays exercise has been to renew confidence in the marks and data provided by the previous owner.  Mark and I also took some other measurements which might be useful at Ripon..

I would appreciate Howard and Philips observations and advice if they have the time at Ripon if Bernard could fix this.

Mark was in the race office at scaling today and he also made some other useful observations. some deserved and  uncomplimentary.  However trim was not a problem....My crew may well be speaking to me by next weekend so we can build on this.... thanks for your time Mark. and thanks to Bernard Phillip and Howard in anticiipation.

Roger
3334

Roly Mo

Roger - we will test out Mark's input when we see you at Grimwith/Ripon/Yeadon!  We'll see you there!