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  #11  
Old 04-29-2015
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Schnick Schnick is offline
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I'd totally believe 800-1000 pounds over for a factory standard J boat of that size, that's in line proportionally with everything I've heard for the 35s.
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  #12  
Old 04-30-2015
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Manana Manana is offline
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Not always excess resin. Resin is approximately equivalent to water at 10 lbs. per gallon.
As mentioned above most quoted displacements don't include interior fit-outs, machinery, or tankage.
See reference above re "Guestimate"...

Henry - Manana was raced under IMS back east. I have numerous single point load cell lift certificates in the 10,500 lbs. range. Lifts done with an empty boat. No water, fuel or equipment. Basically turn her over and shake everything out. I doubt very much she would be anywhere close to that weight now.
Design weight was an optimistic 9,800 lbs. No way I can get down to that weight without judicious use of a grinder and sawzall... May have to put the original 2 cylinder Yanmar back in there too (not gonna happen).

Freeboard measurements done by some measurement rules are moot if the hull shape on file is not accurate. In the case of my old Humbolt Bay 30 the Mount Gay 30 hull form was used. I wish I had that length and hull shape (and foil package).
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  #13  
Old 04-30-2015
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henryr henryr is offline
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It's probably just me being a geeky NA, but I would love to have the Expresses lined up next to each other, and do a quick survey of gear on board and freeboards, just to see how time has treated them.

Similarly, would have been neat to do when J was next to Presto at Heather.

Obviously, the information gained from doing freeboards is only as good as the data used. Garbage in = garbage out. Fortunately, ORC seems to be better managed now than back in the bad old days when you had your issues.
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  #14  
Old 05-01-2015
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I measured the freeboards of my old HF with Horizon (Henryr would know the boat) years ago. I used a tape measure so not the most precise method, but I believe Horizon sat 1" up on the stern and 0.5" down on the bow.

So Horizon was maybe 150 lb lighter - and he had a light 2 stroke engine vs the 4 stroke on mine so close to 40-50 lb right there. Pretty close to the same weight I would say.
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  #15  
Old 05-04-2015
ShawMac ShawMac is offline
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So, I think there was a mistaken measure either going out or putting in, and I think it was on the way out. When we launched Natural High on Friday, we were specific about measuring the weight. The crane operator (and owner) said that the load cell was accurate to within 100 lbs or so. He measured 6500 lbs without the rig, so that is right on the claimed as sailed weight of 6700. We were all very, very surprised.

Either the first operator accidentally carried a 1 when comparing to the tare, or somehow she lost 1000-1400 lbs of moisture in 2.5 months in the shop. I favour the former. She is sitting a bit higher on the waterline, but not that much I don't think. She always sat shallower than her established waterline before.

Schnick will be interested that Willow (Ranger 29) followed at 7400 lbs with the rig on the deck and still lots of knick-knacks on board so not too chronically overweight.
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  #16  
Old 05-04-2015
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Schnick Schnick is offline
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7400 that is not too bad. There is a lot 'stuff' in Willow including a hot water system, heavy SS dodger frame, etc. The propane locker is a welded stainless steel drum that must weigh 50 pounds plus before you even put the tank in it.. Also consider that boat has been in the water pretty much continuously since 1972 - that's 43 years - it has clearly absorbed all the water it's going to absorb.
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  #17  
Old 05-04-2015
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Quote:
Originally Posted by ShawMac View Post
or somehow she lost 1000-1400 lbs of moisture in 2.5 months in the shop.
I think this topic has been discussed before. The only way a 30 foot cored boat could gain 1400 lb of water is is every bit of core in the hull AND deck is replaced with water. Even if the core is wet, I bet there would be less than 50 lb of water in the core. If you did have more and the boat is balsa then you have much bigger problems than simply an overweight boat.
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  #18  
Old 05-04-2015
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Definitely not that much water. That is why I think when the operator said she weighed 7900 coming out, I bet he misread and it was 6900. 400 lbs is way more realistic.
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  #19  
Old 05-07-2015
frfletch frfletch is offline
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I concur that NH could not have absorbed, nor evaporated 1000+ lbs of water. Someone made a mistake.

We weighed Voila with a scale on the single point lift. She was in racing trim and was 4683 lbs. Her designed weight is 3,950. I know from the builder that they never got the weight below 4,350 with no rig or hardware. They argued the case with Farr who suggested they must be resin rich, but they could not get it lower than 4,350 without running into delamination issues. Bruce Farr's cousin worked in the Laser yard in the UK and he could not get them down below 4,350 either. Finally the designer yielded to the idea that his team made an error in calculations, but the brochure had already been printed so they let it go. This adds to the previously mentioned issue of builders allowing lower design weights to be used in the marketing nomenclature, likely fully aware that the boats weigh significantly more. It sort of make a nonsense out of the designed and stated ballast ratios.
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  #20  
Old 05-07-2015
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Quote:
Originally Posted by frfletch View Post
I concur that NH could not have absorbed, nor evaporated 1000+ lbs of water. Someone made a mistake.

We weighed Voila with a scale on the single point lift. She was in racing trim and was 4683 lbs. Her designed weight is 3,950. I know from the builder that they never got the weight below 4,350 with no rig or hardware. They argued the case with Farr who suggested they must be resin rich, but they could not get it lower than 4,350 without running into delamination issues. Bruce Farr's cousin worked in the Laser yard in the UK and he could not get them down below 4,350 either. Finally the designer yielded to the idea that his team made an error in calculations, but the brochure had already been printed so they let it go. This adds to the previously mentioned issue of builders allowing lower design weights to be used in the marketing nomenclature, likely fully aware that the boats weigh significantly more. It sort of make a nonsense out of the designed and stated ballast ratios.
I imagine a lot of it is marketing driven perhaps with an attitude of "everyone else does it" and our boat won't be as appealing compared with boats built for the same market.

I'm surprised the L28 is out by that much. I would think the design weight would include mast and hardware so she is out by almost 800 lb. If you take the design disp of 3900 and back out the 1500 lb ballast and say 800 lb of misc you get 1600 lb hull and deck, which is probably generous. So the 800 extra lb means the hull and deck weight is out by 50%.

As to Farr's initial claim of them being resin rich. I'll assume roughly 50% resin/glass ratio which is on the low side, but will do for a "top of my head" calc would mean if it were a simple matter of being resin rich, the builder would have used double the designed amount. No way the laminate if done to the lam schedule could absorb anywhere near that much excess resin.

Besides the marketing side of things, my guess is also inaccurate or incomplete weight studies, especially in the pre-computer days where everything would have to be hand tabulated. For example were all the toe rail bolts included, cleats, tabbing, hoses etc accounted for or was an allowance simply made for them. I suppose if it were an allowance, the marketing department might find it easy to remove them from the equation. Anyway, just speculation on my part, but I find this side of things interesting.
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