Out boat was hauled today. I was told that based on the crane's scale the boat weighed over 16,000 pounds! They subtracted the weight of the crane's bar and straps to get to that number(aprox. 700 #s) The water tanks were nearly full as well as the fuel tank. Other weight would include the usual anchors, sails, cushions & assorted seasonal paraphernalia. The Catalina manual indicates that "displacement" is just under 12,000#s with a standard keel.
I had the same "overages" with my c27.
Are the yards readings possible? I can't get anywhere near that weight starting at 12,000#s & adding back the extras. If I have that much water absorbed into my fiberglass (i.e blisters & delamination) I assume I'd be sitting a bit low in the water. The boat sails and performs just fine.
Thanks in advance,
Ken
Ken : Back about 1990/91 the was a "ho hum" blivet in the Mainsheet that said something like "BTW the draft of the C34 wing keel is really 4'3" . We missed the design goal of 3'9" !!"
I went down and immediately measured my boat (on the hard) and the article was correct. I'd suspected that anyway.
So I started to ponder and NOT being a marine architect I started to think about known items such as length, width, keel ballast wt. and decided that there was only one item that would cause that hull to sit lower in the water - it was much heavier than designed!!
I've always believed that the C34 displacement is about 15000 lbs NOT 12500. So you're weighing in at over 16000 with full water, fuel and assorted junk sounds about right to me for a 1988 C34!! :roll:
Several years ago I went with the mover to haul Grasmere from Minnesota to South Dakota on a trailer. The trailer had a title weight of 3,950. We stopped at an elevator and had her weighed. Boat and trailer weighed 19,550, so 19,550 minus the 3,950 trailer weight, she weighed 15,600 The water tanks were empty but the fuel tank was about full. The boat was loaded with many extras, 4 batteries, spinnaker, AC, dodger, bimini and just about every other gadget you can think of. I know the grain elevator scale is accurate so 12,500 can't be right. 600 to 700 pounds of extras sounds about right. I think about 15,000 is much more accurate.
steve
Looks like the same for the c42 but it's only about 10%.
http://findarticles.com/p/articles/mi_m0BQK/is_4_10/ai_n14813621
But 15,000 pounds... that's over 25% more than Catalina is listing.
( That makes a j/105 half the weight - with half the room below ;) )
And knocks the keel/displacement down from nearly 42% to 33%...
I guess the upside could be a stronger boat... ?
Is it common for other builders to publish the displacement so much less
than the real figure? 5 or even 10% is one thing but 25% ... wow.
This is a fascinating thread. I find our MkII a handful to stop at a dock if I have made a less than perfect landing. I say to friends that if this is what it takes to stop a 12,000 lb vessel then this is as big as I can manage. I am also amazed that it rides at 3-4" above its load water line and seems unaffected by more chain,water and books. Maybe this is really a much larger vessel than advertised!
I think it is pretty clear the early models weigh in the neighborhood of 15,000 lbs. I am curious if the late models weigh the same or if construction materials and design have lightened them up, or possibly made them heavier. Does anyone have an accurate weight of a late model mk-II?
steve
Displacement of our 1990, C34, standard fin keel, standard rig, integral swim platform, with full tanks, ground tackle, ob and dingy, tools, spares, food, etc., but without crew, is 16,728 pounds. We have seen this measurement twice and both were within 2%. The C34 is a BIG 34 footer, which performs well and is able to carry the equipment and stores that a couple needs for cruising. BTW, our C34 floats above her factory waterline stripe.
About time, I wasn't saying anything, but our 1991 weighed in at just under 17k last year at the haulout for bottom paint with full cruising gear.
I feel better now.
Jim
I know it's been a while since there's been any posts to this thread, but I just bought a 1990 Catalina 34 and during the survey they measured 19,000 pounds! My wife and I were expecting to open a compartment or storage locker and find lead, but every thing's been really clean so far. The boat came with a few extras, but we certainly don't have 7,000 pounds extra ...
Cheers,
Mike
Mike, is your boat (or was it when you bought it) in the water year round? I have a theory (completely unbelabored by fact that fiberglass does take on some water weight, and this action would be aggravated by never having a chance to "dry out" in the off season.
Was the scale calibrated correctly?? Was there tare weight from something that wasn't subtracted out?? Just some thoughts.....
I think there are a number of factors:
-- the factory came in a bit higher than expected
-- weight doesn't include any fluids
-- weight doesn't include any canvas, sails, or lines
-- weight doesn't include any personal objects or optional equipment
-- the hull and deck gain weight from absorbing water over time
It would be very interesting to weigh a brand new c34 before any sails/canvas/accessories were added.
I still doubt it would be 11,900# as the sales brochure suggests....
Craig
Quote from: Craig Illman on March 06, 2007, 12:04:08 PM
I still doubt it would be 11,900# as the sales brochure suggests....
Craig
No, but 12,900 would be in the ballpark.
Well, the surveyor was quite surprised when the yard told him how much, so he went to check the reading himself. Then he asked the yard foreman how recently the lift had been calibrated. The fellow said that it was right on ...
Also interesting, is that the previous owner had a survey done on the boat in 2000, and at that time it weighed in at 16,000# and the same comment was made then ... that it seemed heavy for the stated weight.
So, 7 years later my boat has put on another 3,000#. Hmmm ... didn't realize my boat was like me ... getting heavier with age! :D
Wonder if I decide to go racing whether I'd get credit for being so, >ahem<, portly?
Cheers,
Mike
Ray,
Sorry to burst your bubble, but displacement and weight, as you use them, are EXACTLY the same. Displacement is, as you say, the weight of the water equal to the volume of the boat below the water ("the weight of the water that is displaced"). To use your Catalina example if you put a boat in a full tank of water and weigh the water that spills over the sides it will EXACTLY equal the weight of the boat. Now it is true that the VOLUME of the water displaced will vary depending on the density of the water, but the weight stays constant. There is also another meaning for displacement, which you alluded to, with regards to documenting (sort of a federal registration) a vessel. That has to do with cargo volume which, obviously, is based on the volume of the boat. It is also measured in tons, but has nothing to do with the amount or weight of water the boat displaces.
The following is from an earlier post called C34 Displacement and Tonnage. Furthur info on the same topic.
According to our survey Gross tonnage is listed as 13 tons. Net tonnage at 12 tons. And displacement at +/- 11,950 dry.
What is Gross Tonnage?
Gross tonnage is a measure of the internal capacity of a ship, tug or barge. It is a cubic or space measurement of all areas of a vessel with some allowances or deductions for exempt spaces such as living quarters.
What is Net Tonnage?
Net tonnage is a measure of the internal capacity of a ship, tug or barge's cargo space volume only.
Displacement: the direct measure of the actual weight of a vessel. Displacement tonnage is the weight of water displaced by the hull of a boat. A vessel floating in fluid will always displace an amount of fluid equal to its own weight.
We asked the crane driver who launched my MKII hull number 1657 last weekend. It came in at 18,300 lb. (8.3 metric tons). This is with no mast, full fuel tank and empty water tanks. No gear on board except for anchor and rode. Two 122lb 4D batteries.
Where does the extra 5,000lb come from?? I guess I should not be expecting much acceleration under sail?
On that note, any opinions on the lifting points prescribed in the owner's manual? Most folks here set the aft lift point at the aft bulkhead rather than where Catalina has it marked in the manual.
Tony
For what it's worth, I hauled hull #195 FKSR last month and the lift operator said 15000lbs but aprox. 14000 net , no water, no cushions, no provisions, boat was almost completely empty due to the work I was doing. Boat is in water year round. I thought that was heavy but at 18k lbs...wow...must be a mistake.
George
Fort Lauderdale, FL
If she still does 6+ knots in 12 knot breezes..... :abd:
George : Your displacement sound about right to me. Somewhere between 15000 and 16000 loaded! :thumb:
For what it's worth, I finished bottom paint last weekend and asked the lift operator what the boat weighed as he was putting her back in...right at 1700 pounds with a full fuel tank and about 3/4 full forward water tank. We have all the safety gear plus bedding and normal galley equipment on board. Boat is not loaded for summer cruising yet.
Jack
Oops, dropped a 0 there, should be 17,000 :D
I had my boat hauled this week and was told it came in at 18,000 lbs. Full fuel tank and full starboard water tank, aft tank empty. I've got lots of stuff on it, radar, 8D and 2 GP 27 batteries, bow and stern anchor, two BBQ's, small Honda generator, food for three, and oh yeah, some spirits! Seems to sail fine and doesn't seam to sit low. If this weight is correct should I worry about water in the hull?
Paul : I'd first check on the travellift's strain gages to see if they are correct, as 18K is a little heavy! If they are correct then you could have water in the hull. :think
Just a reminder: mine weighed 18,300 without mast, and with empty water tanks. That was after sitting six months on the hard, with the temperature hitting -30 degrees celsius at times (a home freezer is set at -18). That much water would have split my hull wide open when it froze. Somehow I don't think the weight is water! Maybe a bit more weight in the wing keel?
Tony
Guys : Travelifts are notorious for never having the strain gages recalaberated !! Like any precision tool (i.e. torque wrench or scales etc.) the reading can't really be counted on if it hasn't been re certified/checked.
Most yards do have a moisture meter to give you an idea of how much water your hull has assimilated. :thumb:
Mine was lifted by a mobile "construction" crane, that has mandatory regular calibration. It must be checked regulary, so that they know how far they can reach safely with the load, and not tip the crane off its legs. When my boat clocked 18,00 plus pounds, the operator had to override the safety warning, in order to reach far enough to put me in the water. Other C34's in our club read 16-17K.
Tony
I think Ron is correct about not being calibrated or someone not knowing how to read them. I was there with the yard owner when she went back in. This time the reading was 15,500 lbs.