31 TE Weight

[Tunateaser]

Riddle me this.
The original Brochure I have for the 2006 31 TE has the boat listed at 12,500# This seems light. Every other spec sheet I have read said dry weight 14,000 - 14,400. Just had mine weighed after breaking a lift cable. With 35 gallons of water, empty holding tank and 150 gal of fuel with twin 6lpa=stp engines boat weighed in at 20,500# any Ideas. Did Ablin include the engines, gen set ETC in their calculations?

Eric

[Norseman]

How is it floating on it’s lines?
Sitting deep in the water?
6000 lbs should make a big difference.

[Tunateaser]

Its fine except for crashing off the lift with a brand new 5/16 cable minimum breaking strength 9K I might have had it far back putting 10K per cable making sense BUT why is the boat so heavy?, still cleaning the underwear!!! Some thing is wrong with the original specs.

[Ben423]

The brochure I saw shows a 31TE with a single Cummins 450C. Its dry displacement is listed as 14,000#. The 450c weighs roughly 1,885 lb. The Yanmar 6LPA weighs approx. 900#. But you have to add the weight of the extra shaft, prop, engine beds, mufflers etc. I would guesstimate that adds close to a thousand pounds. Then add 1,050# for fuel, 280# for water. That brings the boat to 16,330# before personal gear. Plus, builders tend to list their boats as lighter than the really are because they don't account for all the little things that add weight, so 20,000# is probably pretty accurate.

[Pitou]

Holy crap! I can't imagine having a cable break. Sounds like youre okay except needing to change your shorts, but how did the boat fare?

Here's my contribution to this:

The Albin Tech Specs Bulletin has the 31TE at 14,000 lbs dry for a twin and 12,000 lbs dry for a single. Not specific to any engine.

Check out the Specs in the Document Library:
viewtopic.php?f=41&t=7052

Add fluids: my engine: coolant (approx 10 gallons), oil (5 gallons)
diesel fuel at 7 lbs per gallon
water at 8.34 lbs per gallon
holding tank fluids .. My Vacu-flush holds 27 gallons

Options that add weight:
anything over 2 8D batteries
generator & optional sound enclosure, battery, fluids and associated gear .... fuel filter, thru hull, sea water strainer, seawater hoses & wiring
windlass, anchor & rode
rear aluminum doors on pilot house
Outriggers, more rod holders

Then there is ALL the gear .. collectively this all adds up FAST!

I have always "guessed" that my boat with a single Cummins QSC tops out around 17,000 plus to 18,000 lbs

[amber jj]

Our boat hauler figures our 31 with the twin Cummins runs about 20,000 or a little better. Our boat has never been over the scales with our current hauler,but that is his estimate from the way it feels when hauled .

[Tunateaser]

Well it does seems like the weight is probably close. The boat is fine. I did realize when I had it weighed that the center of gravity is actually about 18" aft of the center of the sling marks. So it was actually sitting back quite far. I had also guessed 17-18K was about right but I had no Idea it would be over 20. I haven't actually pulled it all the way out of the water since. I'm a little gun shy to say the least. If it is square weight wise on the lift it would be 5K per cable with a breaking strength of 9500 #. still doesn't give me a warm fuzzy feeling. It was on the lift all last winter but I just might have it hauled this winter.

[Makai]

I have never had a boat lift however 5/16” cable seems very small. I know that it probably specs. Out ok however I can only guess that the sheave is a small diameter so the bend in the cable needs to be considered. Another question is where did the cable break , was it right at a bend or in the middle where ? Also I assume that the 9k breaking strength was for the actual cable you bought. Different cable manufacturers have different ratings for the same size cables.

[Tunateaser]

It Broke in the middle. 9,100# is the for the actual cable

[Ben423]

New 5/16" dia. 7x19 wire rope has a breaking strength of approx. 10,000 pounds. Standard practice is to use a 5:1 safety factor for wire rope, or 2,000 pounds max load for that size wire. Quality control, the radius of sheaves and wear are all factors to consider when specifying wire rope. Using this standard, you would use 3/4" dia. wire rope to lift a 10,000 pound load.

[Tunateaser]

Yeah, that is not happening on ANY boat lift. Especially if you are dividing by 4-6 cables.

[Ben423]

You wrote that you were lifting 9,100# with a 5/16" wire cable. It doesn't matter whether you're using a single wire or a travel lift with 2 part or 4 part lifting tackle the same 5:1 safety factor rule applies. 2 part tackle with 5/16" wire rope can safely lift up to approximately 4,000 pounds. A small 15 ton capacity travel lift will often be set up with 2 slings with 2 part tackle at each end of the slings. So that amounts to 8 parts of wire to lift 30,000 pounds (travel lifts are often rated in metric tons, so I'll use 33,000 pounds). That amounts to 4,125 pounds per part. Using the 5:1 rule, it will likely be fitted with 1/2" wire rope. Cranes often use 6x19 instead of 7x19 because it's more flexible. I owned a boatbuilding company for 20 years and used cranes and hoists for many aspects of our production. Fortunately we never lost a load or had anyone injured due to inadequate equipment.

[WillieC]

Excellent info, Ben423. Engineering math and experience. Thank you.

[Tunateaser]

You wrote that you were lifting 9,100# with a 5/16" wire cable. It doesn't matter whether you're using a single wire or a travel lift with 2 part or 4 part lifting tackle the same 5:1 safety factor rule applies. 2 part tackle with 5/16" wire rope can safely lift up to approximately 4,000 pounds. A small 15 ton capacity travel lift will often be set up with 2 slings with 2 part tackle at each end of the slings. So that amounts to 8 parts of wire to lift 30,000 pounds (travel lifts are often rated in metric tons, so I'll use 33,000 pounds). That amounts to 4,125 pounds per part. Using the 5:1 rule, it will likely be fitted with 1/2" wire rope. Cranes often use 6x19 instead of 7x19 because it's more flexible. I owned a boatbuilding company for 20 years and used cranes and hoists for many aspects of our production. Fortunately we never lost a load or had anyone injured due to inadequate equipment.

3 each
Actually the breaking strength of the cable is 9100# the load for some odd reason was 20,500# / 4 cables = 5,125 each. I the boat was loaded evenly regardless of the lift being over loaded the cable would not have parted. After weighing it in a travel lift I find the sling marks have no relation to the actual center of gravity, The real question was why the boat was so far off from the specs? While I knew it was not 14,400 in my head I figured somewhere in the 18,000# range