Heavy v Light displacement

[david_e]

Have just finished reading the article about this by Andrew Simpson in this month's PBO, most informative especially him being a surveyor. I was interested in the bit about the thickness of hulls and also the damage he has seen on heavy boats due to pounding etc. In the end he favours light boats but doesn't go as far as differentiating one Mftrer from another. Any views?

 

[DoctorD]

This will run and run. MHO is:

Light AND Strong is possible and desirable with heavier layup/carbon fibre/kevlar in structural areas and better moulding techniques (e.g. scrimp). My boat (a Maxi 1100) has a superbly moulded and designed hull built in a very advanced factory in Gothenburg. As a result my hull is very strong indeed but the displacement of my (36ft) boat is only 5800 kg. J Boats too have very strong hulls and are lighter still (racing boat lightness).

Some massive steel and wooden hulls are actually over specified in strength or sometimes (surprisingly) are not strong enough in certain areas. Some massivley built GRP hulls have too much resin in them and are therefore overbuilt too.

I like a boat to be strong AND fast. Lightish boats are fast boats. Remember speed is good, so long as you can keep going fast to windward when it blows and is lumpy, and it is not too hard to steer downwind.

 

[david_e]

Scrimp technique

What is this, and do most mftrers do/use it.

I was speaking to J Boats yesterday about one of theirs on brokerage and they were emphasising the build quality and how good a sea boat they are. They tell me that they are built in various countries such as france & usa, look quite good on paper, not sure how much different to ben/jens they are though. The 105 is of interest to me.

 

[oldsaltoz]

G’day David.
Most craft these days are designed as ‘heavy’ or ‘semi displacement’ and the thing they don’t always tell you is that semi displacement hulls are very sensitive to weight. I refer here to your typical motor cruiser type vessel.

Avaniceweekend Old Salt OZ……

 

[billmacfarlane]

Re: Scrimp technique

They have a different philosophy from the typical Ben/Jean/Bav's in that the accent is on performance. Nice interiors though they can be a bit spartan , but the latest ones look plush. The cockpits seem to be laid out with racing crews in mind , and seem a bit old fashioned as they are very angular and don't have the soft curves of some designs. Agree with all the above comments re light and strong hulls but then again I would , also owning a Maxi 1100.
The argument "light v heavy" has been done to death on this forum. Try sailing both and see what you think.

 

[DoctorD]

Re: Scrimp technique

Scrimp is a technique - not yet used by many builders - which allows for a very high percentage of glass fibre to resin therefore making a strong but light hull. Go to www.jboats.com for more info. J Boats for the European market are made in France (to the US J Boat company's designs).

J Boats are very good boats. The 105 is an excellent cruiser/racer or racer/cruiser depending on fitout, with a large competitve fleet. It has a lower freeboard and narrower hull than the Benetau's and Bavarias of this world, therefore less space inside. Also the finish can seem spartan but it is all well made and works very well at sea. And you can sail the socks off most equivalent sized boats.

But as Bill says - go for a sail and see for yourself.

Graham

 

[Chris_Stannard]

The argument about light versus heavy has been well rehearsed elsewhere, one of the main objections to light being excessive crew fatigue in very bad weather. All of the pundits state that heavy displacement boats need to be stronger than their lightweight equivalents to take the extra pounding they get. Its the old old problem, every thing is a compromise somewhere. Its just a matter of what you want a boat to do and finding the best choice in those parameters.

Chris Stannard

 

[david_e]

Re: Test Sailing.

Thanks Bill and Doc, appreciate it has been given an airing even in my short time here, thought the article was of interest though, perhaps a little one sided.

The issue about test sailing is of interest and I would be interested to hear views.

Bought my current and first boat without a test sail, having narrowed the choice down from reading tests and reviews and also looking at the owners site. As it is she has turned out fine and sails better than I thought, previous experience (over 20 years ago) was always in long keelers, Folkboat and Cutlass 27's. I worked on the principle that unless I sailed loads of different boats then just sailing one wouldn't mean alot 'cause I wouldn't have alot to compare it with. With regard to the next boat I am at the stage of narrowing down to a short list in the anticipation that I will be getting a berth soon.

It would be nice to test sail the whole short list but time and distance (not so much choice up north) are against me which is why I am heavy on the research side, is it a grave error not to test sail or do many buy without one?

Also what are the ground rules or expectations if any? I viewed a boat last October, on the water in the marina. It was owned by the broker,mentioned a possible test sail (accompanied) and was told that it would be OK subject to paying a 10% deposit which would be refunded if not happy, I asked if this was normal and was told it was standard practice. Needless to say I didn't bother because of all the potential pitfalls etc.

If a boat is on the hard is it reasonable to be put in before survey for a test sail.

 

[Chris_Stannard]

Re: Boat Choice

Sorry I missed the point of your question. Until recently I sailed a Sigma 362, a smashing boat, which really looked after you in bad weather. It went to windward well and tended to leave most other boats of its size standing. It also went quite well down wind. I originally raced but was converted by SHMBO to cruising and I re- rigged with roller headsail and cockpit reefing. If tyou want a performance cruiser it is a very good choice. From a stabilty point of view the angle of vanishing stability was about 140 degrees.
I now have a NAJAD373, which was much more expensive. This is built to Germanischer Lloyds specifications which are said to be the most demanding for yachts, so I guess that should take care of the pounding arguement. The boat is designed for two people to sail and we have bought it so we can lock the door in the spring and come home in the autumn. It does not sail as well as the Sigma, but it motors a lot faster. It is also a real home from home and very well fitted out inside. Angle of Maximum Stability 78 degrees and Vanishing Stability about 138 degrees.
Why do I quote these figures. A lot of modern boats have angles of maximum stabilty of 50 degrees or less and vanishing stability of 120 degrees. This means they have a higher capsize risk and a greater probability of staying inverted for longer if they do become inverted. You can find a lot of data on www.johnsboatstuff,com which allows you to put in your own figures. It seems to me that, like me you are a cruiser and no doubt, as I do, do your best to avoid heavy weather. But we all get caught out sometime and in my view that means we need crew comfort and that means a heavy displacment boat.

Chris Stannard

 

[kidnapped]

Re: Boat Choice

J Boats only produce smaller/racy yachts in France, and they're more expensive than Ban etc. They produce the BIG BOYS in USA and I'd love to test sail one! Cost? well into HR/Najad/Malo country. In the meantime I've gone heavy... 15T
PS.... Chris are you going to be at Port Solent April 13th ... I think?

 

[hugh_nightingale]

Re: Test Sailing.

10% deposit for a test sail?

Not on your life. After you've said yes and subject to survey, then 10% may be in order.

Try to have a test sail, you may not find out much but you'll see how she (and the owner sometimes) handle things. If you are buying new all the manufacturers offer a test sail and NO deposit. How many did Bill sail before opting for the Maxi, several that I know of, eh Bill.

 

[DoctorD]

Re: Test Sailing.

I concur. I test sailed 6 boats before buying mine. Including ones that had to be craned into the water especially for me. I handed over not one cent until I committed to actually buy one, and then I paid a 10% deposit.

A boat is a big purchase and any reputable broker includes the time and costs of demonstration sales in their commission.

I do know people who have bought boats without sailing them, usually well known makes they have already sailed on e.g. Sadlers, Westerlys etc, but personally I would never buy a boat without sailing it, reefing it, motoring it and generally giving it a good workout.

Graham

 

[billmacfarlane]

Re: Test Sailing.

Too true Hugh. What I found was that the more expensive boats , HR , Malo etc were very accommodating and almost insisted that you had a good test sail before committing to buying. With the less expensive boats , it wasn't suggested and I had to ask. For the record I sailed HR , Malo , Starlight , Maxi and Jeanneau.

 

[david_e]

Re: Test Sailing.

Good, I'm glad you thought that about the deposit.

You are all correct about the test sail, being honest I am probably guilty of being a bit hasty in seeking to buy, wanting to make the most of the summer with the family if and when we get a berth. Makes sense to take a bit longer about it, and although I am leaning towards a Ben/Jen 32' boat, have not ruled out something more traditional like a Sigma 33.