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Old 18 February 2011, 20:42   #1
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Country: France
Town: St Barth d'Anjou
Boat name: Sirius
Make: Pacific 22
Length: 6m +
Engine: Inboard diesel
Join Date: Feb 2011
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Where to put the weight in a Pacific

Hello

New to the forum but been owner to a pac 22 since almost two year that I am slowly rebuilding/renovating. I have decided to install the 170 L tank from Vetus taking out the old tank. Now my question to members with more experience from the pac 22. Shall I put the tank in the existing tank compartment or in the forward compartment. I have measured and it fits both so it is not a question of room. It is more that I would like to what gives the best balance, does she need more weight forward or not. I have made a new engine cover with an integrated console with the helmsman position like the one on the pacific 24. That means that helmsman and the "navigator" will be behind the engine close to the transom. I will also put a beefer A-frame with self-rightening bag and a radar as well. All this give that I will shift some weight from the front to the rear.
Anyone any ideas what that gives to balance. How is she balanced with the original layout and and how sensitive is she to the load? //Thanks in advance.
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Old 18 February 2011, 22:57   #2
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Country: UK - England
Town: Plymouth
Boat name: 2XS
Make: Halmatic Pacific 24
Length: 7m +
Engine: 135hp Honda X2
Join Date: Jan 2004
Posts: 529
Hi
If you put the Vetus tank in the place of the original tank this will leave the forward compartment to be used as a storage hold, the original weight distrubution of the Pac 22 i would say was as near perfect as you can get, i never managed to nose dive it into waves and only once felt it was going to flip backwards, well it was in 3-4 mtr waves with a head on 70-80mph winds at full chat.

Still wish i kept it
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Old 18 February 2011, 23:03   #3
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Country: UK - Channel Islands
Town: jersey
Boat name: Martini II
Make: Arctic 28/FC470
Length: 8m +
Engine: twin 225Opti/50hp 2t
MMSI: 235067688
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This will probably be of interest if you haven't seen it already:

http://www.rib.net/forum/showthread.php?t=1884
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Old 19 February 2011, 10:09   #4
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Country: France
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Boat name: Sirius
Make: Pacific 22
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Engine: Inboard diesel
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OK Thanks

Guys thanks for the tips.
Martini, I read that thread as well as yours on your Arctic 28 impressive work! More or less doing the same though not with the same "speed";
-Taken out the engine and repainted it (Yanmar 4LH-DTE) I will tune it up to 210 hp or what ever I can get out of it (the exhaust temp will tell perhaps I will upgrade the turbo as well to get the 4LH-STE spec).
-Repainting and shorten the engine compartment.
-Redoing the deck with new marine plywood and a layer of GRP
-New console integrated with the eninge cover (done myself in marine plywood and GRP)
-Forward storage compartment with a planus hatch (thought of your alu hatches Martini but Jesus they are not cheap...)
-New A frame a la Delta 740SX (CAD drawing done will be ordered next week from MATC in south France)
-New tubes from Henshaws (Pac 22 MkII (Thanks Chris)) together with a self rightening ba
-New seats (have an idea with a base in stainless stell or GRP supporting tractor seats, sounds starnge I know but I think I will make it work, refuse to pay 3000+ euro per seat for Ullman or similar.
Redoing the layout in other words, very meuch inspired by the Pacific 24 and the Delta 740 which means a layout with aft helmsman position. LIke it more since it gives you control of the passengers (the kids) and free up a lot space on and below the deck.

So Ian if I understands you right you dont see any problem with putting the tank in the aft froward compatrment as Pete7 did even though I might transfer a bit of the other weight to the rear?

Cheers

Petrus
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Old 19 February 2011, 11:09   #5
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Country: UK - Channel Islands
Town: jersey
Boat name: Martini II
Make: Arctic 28/FC470
Length: 8m +
Engine: twin 225Opti/50hp 2t
MMSI: 235067688
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Posts: 3,030
I can only speak for Arctics not Pacs but..

I had some concern over CofG when doing my build, the things I was adding and taking away would've moved the weight toward the stern and I didn't know if my bow was going to end up to flighty.

I even put a small access hatch going forward inside my forward under-deck locker. The idea was that I could get access to the tip of the bow to fill it with lead at a later date if required.

Turns out my fears were completely unfounded, the Arctic runs very flat in all conditions. I find most ribs are happy in a following sea but working hard to keep the bow down in a head sea. I on the other hand am quite happy in a head sea and feel more vulnerable in a following sea, the tendency for the bow to stuff is quite strong! Although I suspect this might have a lot to do with the design of spray rail on the bows rather than just weight distribution.

Obviously none of the above may necessarily apply to your Pac but I suspect needing more weight in the bow isn't going to be an issue.

In short, I'd say put the tank back where the old one was.
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Old 19 February 2011, 22:54   #6
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Country: UK - England
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Quote:
Originally Posted by Latitude65N View Post
OK Thanks


So Ian if I understands you right you dont see any problem with putting the tank in the aft froward compatrment as Pete7 did even though I might transfer a bit of the other weight to the rear?

Cheers

Petrus
Hi Petrus
I have some paper work with the measurments of the C of G, i will dig them out maybe some use in positioning counter ballast weight, the tank is forward of the C of G anyway, so the bigger the better.

Either side of the forward big space (in front of the fuel tank) there are spaces, i am going to fill mine with steel punchings to counteract the two outboards that i want, instead of an inboard there are also some other smaller compartments right up to the bow you could fill them as well.
Ian

In my pac i sold, i had a tank made and the was 190ltrs, wanted to fit the Vetus one but one of the bearers was an inch out at the bottom so it wouldn't fit
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Old 24 February 2011, 22:59   #7
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Country: UK - England
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Hi Petrus
C of G is 1850mm from the stern base, hope this helps.
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Old 24 February 2011, 23:12   #8
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As per almost every planing hull - about 1/3 of the way forward.
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