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No sam.

 

Gary runs a business building boats.

I have made an arrangement with Gary to build me two amas.

He has agreed to that for a certain price.

 

It is costing me what I expected and it is taking him the time that we both expected.

 

It is not the place to discuss private arrangements online.

 

Your estimate is a long long way over the top.

 

BTW our estimated ama weight is 75 kg

 

I wasnt asking about the financial arrangements just curious to see how long it takes a couple of pros to build some carbon floats.

 

Me and George were hoping to take 600 hours but it was more like 800 to do our tortured ply floats with a bit more fairing and painting yet.

 

 

Ha Ha Ha, Totally busted !

 

I never really properly worked out how much the ama was going to weigh, and never did a weight study or anything like that.

 

The basic premise was that the new amas were longer and lighter than the old one's and have similar amount of rocker.

Therefore that should be enough to make them faster than before.

 

Bullshitting about the weight being 75 kg has come back to bite me !

 

It weighs 125 kg !

 

and still has tramp tracks, chainplates, gudgeons, paint etc to go.

 

But that aside it still looks very cool.

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I told Gary a while back id give him a bottle of rum if they were under 100kg each...

 

Can we be sure this is not your way of saving your handicap and they actually weigh 60kg???

 

How much were the old ones?

 

Because the person I know with the biggest mouth saw me weigh them I had to 'fess up.

Word was going to get out there any way !

 

We aren't exactly sure how much the old ones weighed but I have lifted the old ones on a number of occassions, as have Bryan and Jason, these are definitely lighter, but to be honest I am not certain by how much.

 

These ones are a good deal bigger though at 22 square metres of surface area, and when fully submerged will displace around 3500 kg

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Ok, so I said it wrong.

 

Here is my point though.

 

Our sailing displacement is 1450 kg, so the buoyancy of our new ama is 240%? (Being 3500/1450 x 100)

 

When I bought Wolfy it was claimed it had 200% amas, but when you flew the main hull, the gunwhale of the ama was virtually level with the water, and there was very little reserve.

 

I think a lot of people state there ama buoyancy % using the weight of the bare boat, not the Sailing Displacement, including alll crew and all additional gear on board?

 

so if my new ama is 240% then are Lucifers and Sam's new boats amas really 350% ?

My sailing displacement is only a few hundred kilos heavier than Lucifer, so wouldn't those 8.5 amas need to have 4400 kg of buoyancy to be 350%, I know they are big but where is all the extra volume? they are giving away a decent amount of length, and our ama is still 900mm deep by 600mm wide.

 

Or is this not how you work it out ?

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Ok, so I said it wrong.

 

Here is my point though.

 

Our sailing displacement is 1450 kg, so the buoyancy of our new ama is 240%? (Being 3500/1450 x 100)

 

When I bought Wolfy it was claimed it had 200% amas, but when you flew the main hull, the gunwhale of the ama was virtually level with the water, and there was very little reserve.

 

I think a lot of people state there ama buoyancy % using the weight of the bare boat, not the Sailing Displacement, including alll crew and all additional gear on board?

 

so if my new ama is 240% then are Lucifers and Sam's new boats amas really 350% ?

My sailing displacement is only a few hundred kilos heavier than Lucifer, so wouldn't those 8.5 amas need to have 4400 kg of buoyancy to be 350%, I know they are big but where is all the extra volume? they are giving away a decent amount of length, and our ama is still 900mm deep by 600mm wide.

 

Or is this not how you work it out ?

 

Yes Tim some people use the boats weight and some people use the sailing weight inc crew, which is prob a better way of calculating it,

 

so we should be 900kg(inc cat 5 safety gear) +50kg (sails) + 300kg (crew and lunch/beer) so 3500 / 1250 = 280% floats, not 350% as I said before.

 

Even this sort of ratio theres bugger all freeboard on the floats when the main hulls flying high especially when sailing with 4 not 3 and wet sails etc.

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Wed Sep 22, 2010 12:37 am

we wont be useing the denny weight calc sheets ( sorry rob just joking )

Perhaps you should have. 75kgs vs 125kgs, with more to come is pretty embarrassing for professional builders. (sorry gary, unfortunately not joking)

 

Sun Oct 03, 2010 12:08 pm

So to summarise.

we don't know what we are doing.

......snip...........

At approx 75 kg our new amas are heavy.

 

I disagreed with you when you wrote this, but it looks like you were partially correct.

 

However, you have a really low opinion of your fellow sailors if you think they are gullible enough to believe that one of the most experienced composite boat builders and multihull sailors in NZ, with the help of one of the most careful designers, really put all that time and effort into designing the hulls for his pride and joy but "never really properly worked out how much the ama was going to weigh, and never did a weight study or anything like that." before telling everyone what it would weigh?

 

You should have asked! It is the least I can do after you were so helpful with your extensive, detailed (and totally wrong, but what the hell) analysis of the weight of my proa, even down to the 40 grammes of glue to join the foam together, and the weight of a coat of primer.

26 sq m (22 plus say 4 for bulkheads, sheer web, dagger case etc) of 500 gsm carbon cloth/10mm foam/200 gsm carbon cloth (2.5 kgs/sq m) is 65 kgs, plus say 10 kgs of uni for the bows is 75 kgs if it was vacuum bagged. Plus overlaps (2 kgs), hand laminating (13 kgs), the flanges required for a hull built in 2 halves (5 kgs), chainplate (2 kgs), gudgeons (4 kgs), dagger case (3 kgs), beam sockets (5) glue to join the two halves (7 kgs), and bog (2 kgs) is 43 kgs. Total 118 kgs.

 

That took a couple of minutes using guesses for the dimensions and details and is within 5% of the weight so far. Done properly using my "weight calc sheet" it would have taken an hour and been within 1%.

 

70% more materials than you allowed for makes your claim that it is on budget look bizarre as well. Or did you never really properly work out how much the ama was going to cost, and never did a cost study or anything like that, either?

 

Good try, laughing at yourself in the hope that no one else does, but a 70% error in the weight with more to come, is almost certainly a world record for a race boat. Your statement that you would have kept it a secret if you hadn't thought it would get out anyway does not do you or the industry much credit either. Do you apply the same rationale to the masts you build?

 

But don't worry. A couple of weeks of sanding and a glossy paint job and everyone will forget how much it cost and weighs.

 

By the way, you never answered the questions at the end of viewtopic.php?f=37&t=13974&start=80.

 

rob

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