Balast Questions

[sasailor]

Good day to all contributors, I am a new resident on the list and need your advice – sorry to come begging right at the start without first helping out – fact is you guys are a lot more knowledgeable than me -))

I am hoping that you can assist me with a suspected ballast problem, I am in the process of purchasing an Elvstrom Quarter Tonner, a 25 foot racing sloop. She has a horrible reputation in Durban (my home port) for being virtually uncontrollable downwind and extremely tender.
Having been aboard I think I know what the problem is and I think I have seen proof of it. The first time I noticed the boat it had overbalanced onto its bow during kedging. When I went aboard I saw that at some stage in its past – and looking at the fittings it was original equipment – it had an inboard marine diesel. This has been removed and nobody compensated for it’s loss in terms of weight. So the questions are as follow:
First - does anybody on the board know the design – if you do, do you know which marine diesel they installed (Swedish boat – possibly Volvo?), More to the point what did the motor and gearbox weigh (Kilograms please) – I think the lack of approximately 350 kg of weight below the waterline behind the keel accounts for the boats behaviour. (Do you think I am on the right track here?) I do not wish to move the keel as this has never worked in my experience – aside for as a means for boatyard owners to buy new luxury cars.
Second - What is the best way to add ballast to a GRP yacht – I have considered things like bolting in pieces of railway track to the existing motor mounting. I would really appreciate any light the board can cast and advice you can spare me.
Kind Regards and complaints of the Season


Tel +2731 267 0646
Cell +278234 22 33 6
Durban South Africa

 

[Guest]

Sorry, don't know the design.

The easiest way to add ballast is in the form of lead pigs securely fastened in the bilge. Scrap lead is pretty cheap, in the UK, my scrap metal merchant pays me
£ 300 per ton. casting the stuff is a cinch. Sand to form the mould, a variety of sausepans, when no one is looking, and away you go.

A classier alternative is to cast a lead shoe to go on the bottom of the keel. Watch out for structural over loading though.

It might me worth getting in touch with the RORC rating office, they might have records, or a copy IRC certificate which would help. Sorry I don't know their address, but you should be able to get in touch via www.rorc.org.uk

Enjoy your summer, whilst we're freezing up here!

 

[sasailor]

Thanx for the info Mike, will follow up - they seem to be having server problems right now - who isn't.

Tel +2731 267 0646
Cell +278234 22 33 6
Durban South Africa

 

[oldsaltoz]

G'day Juan, and welcome to the forum,



This sounds like the same problem Holland 30's have. If so placing ballast will NOTcure it, the problem is one of basic design.



If my memory serves me correct they were designed to comply with a measurement rule, (IOR or half ton, I can't remember) as a result they have a tucked up canter at the stern and a very narrow transom. Pigs down wind till you work out the best trim for the main and be very fast at letting it go or getting it on too far when running downwind. Very good upwind and fantastic in light air upwind.



I had the pleasure of delivering one from Cairns to Brisbane a few years ago, one of the few deliveries where I looked forward to head winds.



Perhaps one of our Holland 30 owners can throw a little more light on the subject.



Avagoodweekend Old Salt Oz /forums/images/icons/cool.gif

 

[aod]

Down wind sailing is a common IOR problem because the boats dig their noses in and all hell breaks loose.
The fact that you have no engine which was located abaft the keel MUST affect the trim and indeed increase the buoyancy aft of the keel. This would in effect make the boat more buoyant exactly where you don't want it, accentuating the problem of lack of buoyancy in the bow (sailing along arse up) and thus the tendency to dig in the bow.

The solution in your case would be to glass in lead blocks using fibreglass webbing and epoxy resin into the bilges where the engine would have been. (If you glass in too much you can chisel through the strops and remove it).

Another tip when you are running to have the crew as far back in the boat as possible, and I do mean as far back as possible. You can also stick a reef in or even two reefs if it's windy, and also try and keep the stored sails aft. The kite will try and lift the bow and the main will try and force it down thus if you reduce the area of the main you in turn reduce this leverage.

I am not guessing here I have raced an IOR three quarter tonner for five years.

Hope this helps!

 

[gunnarsilins]

Sorry, beeing picky....

....but Paul Elvstrom is not Swedish, he´s Danish! So if guessing what engine there was you also should consider a Bukh.
Merry Christmas greetings from s snowy Stockholm!

 

[Jacket]

If the inboards been removed, does it have an outboard on the stern instead? Because if it does, I'd have thought the extra leverage due to it being mounted further back would make up for the lighter weight of the outboard compared to an inboard, and the boat would still be trimmed similarly. Of course, the centre of gravity would be higher.

 

[sasailor]

The geniuses never thought to mount the outboard - used to tow it out of the moorings with a dingy - to the amusement of all - 5 hp Yamaha - dont think it would compensate as it's pretty new - 98 model - thanks for the thought though - am going to mount a pivoting dive platform that will double as outboard mount. I think this will allow me to get the maximum pivot out of the outboard and use the drive to turn the boat instead of relying on the rudder - if it works as I am hoping it will I should be able to spin her around in her own lenth - am playing with the idea of running a gear and chain arrangement off the rudder post - but this will complicate the pivoting of the platform no end.

Tel +2731 267 0646
Cell +278234 22 33 6
Durban South Africa