Boatmad.com


Reply
 
Thread Tools Display Modes
 
Old 30-03-2004, 10:20 PM   #1
Registered User
 
glen76's Avatar
 
Country: england
Location: southampton
Occupation: engineer
Interests: lots
Boat make: scorpion 8.1
Engines: 250HO
Cruising area: solent

Join Date: Mar 2004
Location: southampton
Posts: 1,353
bow tanks

not having a bow tank im curious,

1stly where do you put them, up high? down low? over the nose or centre?
2ndly how much capacity and weight do they add??
oh and lastly how the feck do you use em. Is it not an accesory that a well designed and balanced boat shouldnt need

thanks
__________________

glen76 is offline   Reply With Quote
Old 31-03-2004, 07:26 AM   #2
BananaShark Member
 
Cookee's Avatar
 
Country: UK
Location: Salcombe South Devon
Occupation: Racer and builder
Interests: Winning races
Boat name: BananaShark
Boat make: BananaShark 34' Race
Engines: Twin Yanmar BY 260's

Join Date: Mar 2004
Location: Salcombe South Devon
Posts: 4,638
Re: bow tanks

Quote:
Originally posted by glen76
not having a bow tank im curious,

1stly where do you put them, up high? down low? over the nose or centre?
2ndly how much capacity and weight do they add??
oh and lastly how the feck do you use em. Is it not an accesory that a well designed and balanced boat shouldnt need

thanks
Glen -

Bow tanks are usually right up in the bow - any well set up performance boat should have its weight down low - a low centre of gravity is important. There are also saddle tanks which are put further back in the boat to add more weight to the boat for very rough conditions.

As far as weight / capacity is concerned it varies depending on the size of boat - a Phantom 18 might only have 50 litres or even less, whilst our raceboat has a 150 litre tank with a 3000 gallon per hour pump to empty it!

They are very simple to use - there is a pick up at the transom which can be lowered to scoop up water, and at 50 or 60 mph you can fill a tank quite quickly! This is often operated by the navigator. To empty the lever (often an adapted gear lever using the same type of cable) is pushed the other way and the fill becomes the dump and the water rushes out the way it came in.

As everything in this world is a compromise you can never have a perfectly designed boat for every condition - these things are usually only found on race boats although some leisure boats intended for "heavy duty use" may also have them fitted - another way of "ballasting" a boat is to have more than one fuel tank so that you can move fuel fore and aft depending on the conditions.

Bow tanks are used when heading into the waves when you would normally trim the engine in to prevent the bow heading skyward - and then emptied when heading downwind when you would normally trim the engine out to prevent the boat from stuffing.

I hope that explains the use of bow tanks - I'm sure someone else will have something to add or tell me I'm wrong!

__________________

__________________
Cookee



British Champions! RIB Formula 1 2005
National Speed Record Holder at 90.15 (still)

www.bananasharkracing.com
Cookee is offline   Reply With Quote
Old 31-03-2004, 09:21 AM   #3
Ian
Registered User
 
Location: Cheshire

Join Date: Mar 2004
Location: Cheshire
Posts: 137
Re: Re: bow tanks

Quote:
Originally posted by Cookee
Bow tanks are used when heading into the waves when you would normally trim the engine in to prevent the bow heading skyward - and then emptied when heading downwind when you would normally trim the engine out to prevent the boat from stuffing.
Please forgive my ignorance on this topic as most of my boating activity is spent waterski-ing on a flat bay. I do nip round the headland etc from time to time but at a steady pace for the kids to look at the birds (feathered variety) but I would like to go a bit further afield and yes....I know...I should really get myself some professional training.

My question is this....If the bow was trimmed down when heading in to the waves, would this not increase my chances of 'stuffing it head first' in to a wave. Does the rule of thumb that you mention only come in to affect over a certain speed.

Many Thanks
Ian is offline   Reply With Quote
Old 31-03-2004, 09:45 AM   #4
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
Ian
where abouts do you boat?? must be North Wales, Abersoch, Morfa Nefyn? if you come from Cheshire??

I believe (or though I'm no racing expert) Cookee means on the plane, so normally into the waves your bow would always point skyward and the boat would smack down on its stern...

We almost sunk our extreme26 in a big following sea of the needles last year... we had her on full trim up, doing 15mph, but the waves were so big they just pushed the nose down into the next swell and we got a few swampings!!! Was a scary experience!!
Admiral P. Brain is offline   Reply With Quote
Old 31-03-2004, 10:34 AM   #5
Ian
Registered User
 
Location: Cheshire

Join Date: Mar 2004
Location: Cheshire
Posts: 137
Admiral,

Correct ! Anglesey, North Wales.

Now then, cookee says 'keep the engine trimmed in to prevent the bow from going skywards' (in to the waves). But I'd have thought if you keep the bow down its going to go straight through the oncoming wave.

Have I lost the plot?
Ian is offline   Reply With Quote
Old 31-03-2004, 10:55 AM   #6
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
Theres trimming in and TRIMMING IN !! depends on boat set up I suppose..

normally the boat, even trimmed in, would ride the front of the wave ok, cookee is talking more about going over and past the wave..

Sometimes depends on the hull shape

We run our boat trimmed out on a flat sea to get water contact on the flat pad at the stern (however on freak swash and we are skywards)

Whilst in the chop we trim in to angle the hull flat to use the deep v at front/mid section to cut thru the waves and cushion the ride...


used to live in Wilmslow and do all my early boating when i was a nipper in Morfa nefyn and Absercoch (1984-88).... little 13 and 15ft fletchers anything bigger than a 60hp was pure show off!!!
Admiral P. Brain is offline   Reply With Quote
Old 31-03-2004, 11:11 AM   #7
Ian
Registered User
 
Location: Cheshire

Join Date: Mar 2004
Location: Cheshire
Posts: 137
It's a small world....I'm in Wilmslow now!

Used to go to Morfa Nefyn about '87 '88 fight on the slipway next to 'The Cliffs' spend a day on the girlfriend's father's 15' Glastron - 80 Merc. Back to the caravan at Pystll for a brush up and then back to 'The Cliffs' for another fight....this time with Aled the one-eyed local. Did you ever try their Ckicken Curry. It was soooo good.

I used to get on well with a couple of the locals. One was crew on the lifeboat although we never met professionally so to speak.

Did a couple of trips over to Abersoch as well and used the park and launch opposite Land & Sea. Good Times..............
Ian is offline   Reply With Quote
Old 31-03-2004, 11:20 AM   #8
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
yeah they were great times

used to sneak into the cliffs (was only 16 in 1987 )
and play the machines and pool, yeah i remember the one eyed locals!!

my folks had a cottage at the top of that beach road...
used to spen most time on water or over at the ty coch pub on the beach....

used to live on Hawthorn lane no 16 untill 1990 my folks moved away 2 years ago... still go back for the odd wkend good friend lives in mobberley, so many new bars now!!!
Admiral P. Brain is offline   Reply With Quote
Old 31-03-2004, 11:31 AM   #9
Ian
Registered User
 
Location: Cheshire

Join Date: Mar 2004
Location: Cheshire
Posts: 137
So many new bars and so little time.
Ian is offline   Reply With Quote
Old 31-03-2004, 11:36 AM   #10
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
so do you boat now the menia straits?? need a rya sailing couse round there early 80's didnt like those swrils currents 'swellies' they call them!!
Admiral P. Brain is offline   Reply With Quote
Old 31-03-2004, 12:18 PM   #11
Ian
Registered User
 
Location: Cheshire

Join Date: Mar 2004
Location: Cheshire
Posts: 137
No East Coast between Benlech and Moelfre.

Want to try the straits this year but not alone. (old outboards, swellies, rocks etc) thought about launching from Menai Bridge turning right under the two bridges and heading out past Port Dinorwic then up the west of Anglesey to Llandwyn Island for the day.

There is a good place to ski just off Plas Newydd on the Anglesey shore of the straits but again.....never tried it.

I could do with a Fourwheel drive for the slips though then I don't have to worry about tides. At the moment, If the tide isn't on the slip I just handball the boat and trailer in and out off flat sand. But the slips at Menai Bridge, Beaumaris etc. go to a rocky surface when the water is low and they are quite steep.
Ian is offline   Reply With Quote
Old 31-03-2004, 12:24 PM   #12
Ian
Registered User
 
Location: Cheshire

Join Date: Mar 2004
Location: Cheshire
Posts: 137
This is what the Swellies can do to ya.

HMS Conway being towed through the straits, broke free and ended up breaking her back in front of the watching thousands.
Attached Thumbnails
Click image for larger version

Name:	conwaythree.jpg
Views:	354
Size:	29.5 KB
ID:	159  
Ian is offline   Reply With Quote
Old 31-03-2004, 12:27 PM   #13
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
yep we used to have an old landrover pull the boats anywhere...
its all so easy now in Poole they plonk it int he water... then scoop it up when u've finished!!
Admiral P. Brain is offline   Reply With Quote
Old 01-04-2004, 10:40 AM   #14
Registered User
 
glen76's Avatar
 
Country: england
Location: southampton
Occupation: engineer
Interests: lots
Boat make: scorpion 8.1
Engines: 250HO
Cruising area: solent

Join Date: Mar 2004
Location: southampton
Posts: 1,353
thats not the rmyc is it?
glen76 is offline   Reply With Quote
Old 01-04-2004, 10:46 AM   #15
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
nah cobbs quay sh*tty end of the harbour but one of the few that operate a racking system
Admiral P. Brain is offline   Reply With Quote
Old 01-04-2004, 11:06 AM   #16
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
hold your breath £2,800 for the year !! for 26ft
include exta £100 for the 1ft bathing platform !!

saves me £80 on antifoul !!
Admiral P. Brain is offline   Reply With Quote
Old 01-04-2004, 12:01 PM   #17
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
you never know !!
yeah you wanna keep that boat out of the water and slipping it yourself often ruins the days boating!!

is everything done then?? what mods you made so far??
Admiral P. Brain is offline   Reply With Quote
Old 01-04-2004, 12:32 PM   #18
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
Crumbs thats a lot of work.... suppose that why these boats plummet in value from new!!

bit of a squeeze in that engine bay eh!!! not suprised with those lumps youve got in there... remeber breath in!!!

when i launched redmist last wkend found Tony Davis wedged in the bilge sorting out the transducer!! thought he might of been down there since christmas!!! we had to hire the crane to get him back out !!!
Admiral P. Brain is offline   Reply With Quote
Old 01-04-2004, 12:50 PM   #19
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
We just drop a cheeseburger in the bilge and Tony's soon down there!!!

only joking of course he's finished RedMist, mended all the minor dents we made last year added some new trick bits and its as good as new again!!! all part of the service he provides!!
bring on the summer!!
Admiral P. Brain is offline   Reply With Quote
Old 01-04-2004, 01:17 PM   #20
Registered User
 
Country: Lymington UK

Join Date: Mar 2004
Posts: 501
new machined stainless switch panel to be engraved...

new polished alli steering hub extension (eddiemarine california)

better drainage system for engine hatch lip

new cabin fitting for secure storage

replaced damaged gaffrig throttle

new shiny red fusion coated grab handle on stern to get up the ladder after too many beers!!! (eddiemarine california)

new bennet sport tabs, old ones paint finish had come off

new transducer for garmin thru hull previous external one ripped off on a high speed run!!

repaired upholstery and other little bits...
__________________

Admiral P. Brain is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Powered by vBadvanced CMPS v3.2.3

All times are GMT +1. The time now is 05:41 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
×