Griffon Centre of Gravity - Fore/Aft

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Swirley
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Griffon Centre of Gravity - Fore/Aft

Post by Swirley »

Hi, Does anyone know where I could get a drawing that shows the centre of gravity on a Westerly Griffon Mk1 Bilge Keel? I have the chance of a strong (but short) trailer, to move the boat a short distance for winter storage. The trailer's flat bed will take the keels, but not the rudder. Assuming the CoG is around the middle of the keels and not too high, this should be OK. I would sleep better though after seeing a side view of a Griffon with the CoG shown.

Here's an example of what I'm looking for...

Image

Thanks in advance for any help.

Best Regards,

David
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Re: Griffon Centre of Gravity - Fore/Aft

Post by Jolly Roger »

There may be another Griffon owner who can advise. If not a phone call to the Ed Dubois yacht design studio should give an answer.
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Re: Griffon Centre of Gravity - Fore/Aft

Post by aquaplane »

I would suggest that you need to suck it and see.

Plonk the boat on the trailer and see if you can lift the tow hitch. If you can't it's too heavy. If it's too easy or the rig tips backwards you got it wrong the other way.

For a short tow at low speed you may get away with it, just don't do 50 MPH and hit the brakes.

How short is your short trip? If it's very short and it's a recognised route between a lift out spot and a storage place plod may not bother you overmuch. There again, they might.
Bob.
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Re: Griffon Centre of Gravity - Fore/Aft

Post by Swirley »

Jolly Roger wrote:There may be another Griffon owner who can advise. If not a phone call to the Ed Dubois yacht design studio should give an answer.
Thanks Jolly Roger. Dubois gave advice by email... estimating the longitudinal CoG as being towards the back of the bilge keels.
The mast lowered etc. will all have an effect of course.

The move went successfully. Thanks again.
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Re: Griffon Centre of Gravity - Fore/Aft

Post by Chris H »

My Griffon II is now out on its trailer and I can confirm that it balances almost exactly on the middle of the bilge keels perhaps about 50mm behind the centre.
However, I should add that I do have 120ft of chain in the anchor locker but balanced by the Bukh engine (is there a heavier engine?) and full fuel tank behind the CoG.

I hope this helps

Chris H Pinar GN400
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Re: Griffon Centre of Gravity - Fore/Aft

Post by Swirley »

Hi Chris, Thanks for your note. It's reassuring that your practical experience ties up with the theory.
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