Moving Ballast ( ie mobile corrector wieghts)

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Zecc
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Moving Ballast ( ie mobile corrector wieghts)

Post by Zecc » 17 May 2004, 10:40

This may be a flight of fancy, but I was wondering the other day about a movable ballast system within the IOM hull which actually takes my correctors wieghts and places them within a mechanism ( I have some prelim ideas on how to do it ) to be able to alter the trim of the hull slightly with sheeting position.

I was wondering if anyone had opinions ( :) ) on this from a legallity perspective and from a practicle effectiveness point of view?

Thinking back to my skiff days I have many fond memories of my helmsman cracking me on the back of the head telling my to shift my self aft (obviously I wasn't moving quickly enough for his liking). I was wondering if the same principle of shifting available weight aft down wind held true at a smaller scale in an IOM?

Anyone?

From a legality point of view, I checked the rules and dont see anything there which precludes it ( I am willing to stand corrected, rules interpretation are not my strong point), as long as I dont intend to have it sticking out of the boat or use a seperate channel and servo to control it.

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Re: Moving Ballast (ie mobile corrector wieghts)

Post by Chairman » 17 May 2004, 11:02

Zecc wrote:From a legality point of view, I checked the rules and don't see anything there which precludes it
Hi Zecc

The class rules say at "C.4.3 CORRECTOR WEIGHT(S)", that "Corrector weight(s) [...] shall be fixed in/on the hull".

The Equipment Rules of Sailing say at "B.10.1" that "Corrector weights shall be securely fixed".

And Appendix E to the RRS says, at "E4.7 Moving Ballast", that "During an event [...] ballast shall not be shifted, shipped or unshipped".
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Zecc
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Post by Zecc » 17 May 2004, 11:38

Well I did say rules interpretations weren't my strong point :D

Thanks very much Lester for setting me straight.
Peter Zecchin - AUS756

Roy Thompson
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Post by Roy Thompson » 17 May 2004, 17:05

On the question of moving ballast - we are trying to devise a way to ensure that in the upcoming Europeans 2004, ballast doesn't accidentally (or deliberately heaven forbid) move about during the event. We have an old and very small supply of self destructing (if moved) stickers as used by dinghy sailing event measurers but we can't source more. We have thought about a simple 'blob' of silicon or something similar, or even digital photos and a description, although for most of these good access is neccesary.

Any other ideas (tried) out there ??? (We're talking about the more or less permanent ballast used to bring the boat up to the 4kg minimum limit, not the ballast used to equilibrate rigs so that they all weigh +/- the same to keep the boat within the limits when you change rigs.)
Roy Thompson
"WE DON'T SEE THINGS AS THEY ARE, WE SEE THINGS AS WE ARE" A.N.

Greg Vasileff
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Post by Greg Vasileff » 18 May 2004, 03:08

......on this topic also, there is a new concern about moving ballast "I" believe, and that's the new thinking of having a bulb with adjustable canting by the turning of a couple of screws or bolts on the bottom of the bulb. How does one monitor this during a regatta? Adjusting the angle of your bulb is moving ballast, not to mention possibly changing the depth of the keel past maximum.
Greg V

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Post by Chairman » 18 May 2004, 11:32

Greg Vasileff wrote:Adjusting the angle of your bulb is moving ballast
Hi Greg

Yup, I think the rules are quite clear on this.

It is interesting that removing the IOM keel (for storage, perhaps, at the end of a day during a multi-day event) is also technically "moving ballast", and so there is a submission to change E.4.7 to allow "fixed" ballast, such as a keel, to be moved:
Submission: 142-03 wrote:PROPOSAL:
E4.7 Moving Ballast
Rule 51 is replaced with:
During an event and unless class rules specify otherwise,
(a) moveable ballast shall not be shifted, shipped or unshipped; [...]

REASON:
This will allow that keel with fin and bulb can be removed between two days of an event.
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Roy Thompson
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Post by Roy Thompson » 18 May 2004, 16:57

Greg wrote:
How does one monitor this during a regatta? Adjusting the angle of your bulb is moving ballast, not to mention possibly changing the depth of the keel past maximum.
Yes, good point. I guess the total draught of the hull/keel that remains within the limits as checked by the tank is still legal. It's a 'yes it's within the limits' or 'no it's not' question, and not a question of 'hull and keel draft are xxx millimetres'. This is something we need to think about. Being able to measure the angle of bulb cant is a process which is at best a bit tricky in the warm confines of a workshop using a very carefully prepare jig etc and it would be quite difficult to undertake this type of millimetric measurement during an event even if desirable.
So where does that leave us - with another rule which is difficult to check (like aluminium grades, variations of wall thicknesses of alloy tubes etc...) but in it's essence is trying to avoid certain specific things - in this case the gross movement of 'fixed' ballast. How much movement is allowed? Zero? Well we can't event measure it too easily if we're talking about bulb cant. That's the problem. The solution?????...
Answers on a postcard to....
Roy Thompson
"WE DON'T SEE THINGS AS THEY ARE, WE SEE THINGS AS WE ARE" A.N.

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