Boat and Trailer weights

[mccaughd]

Howdy all,

My boat resto is taking its time but slow progress is being made.

Last night, with a group of friends, we got the boat (hull only) off the trailer so that the trailer can have some work done to it.

The 4 of us struggled with the hull due to its weight. Which has posed the question...How much does it weigh?

Are there any questimations as to how much a dual cockpit 4.8m timber clinker might weigh with no engine?
As a reference, my boat looks similar to Greg's "Stormy". I have a Chrysler engine that is no feather weight at approx 295kg to go in the boat.

As part of the trailer resto, a new axle is required and i have been budgeting on having to buy a 45mm axle, however if I don't need such a big axle due to my over estimation of weight, i can look at a smaller size axle.

By the way, I blamed the weight on the last coat of varnish.

Cheers

Damien

[Alan]

Damien,
when you have the boat upside down, get three blocks all the same height as some bathroom scales and put one under each corner. Then swap the scales one at a time for one of the blocks and record the reading, add all three readings together and that's the total.

The more the boat is level the more accurate the corner weights will be, but the total should always be close. I have only checked butter boxes which usually start around the 150kg for 14-15 foot.

It will be interesting to see what it comes out at (I wonder how much all the oil soaked into the hull weighs0. BTW, when I looked up specs for my mates 21 foot ski craft (F/Glass) it had bare hull weight of 800kg!!!!

Alan.

[mccaughd]

when you have the boat upside down, get three blocks all the same height as some bathroom scales and put one under each corner. Then swap the scales one at a time for one of the blocks and record the reading, add all three readings together and that's the total

Thanks Alan,

As of last night the boat is upside down on the pavers outside (covers on of course) so the method you have described is very easy to perform.

When i asked the boys last night after we had lifted the boat how heavy they thought the boat weighed their responses were "Fk'n heavy", "Way too heavy" and "Bl00dy heavy". At least now i have a method to calculate each of those descriptions

FYI, i corner weighted my sports car using bathroom scales and it was fairly close with some maths added in.

Cheers

Damien

[mccaughd]

No wonder the boys complained about the weight.
These were taken in the dark, while raining, not 100% level ground with el cheapo scales and boat bow down.
Bow 100kg
Port stern 75 kg
Starboard stern 80kg
Total 255kg

If the boat was 100% level i would have expected the numbers to be more even but this has given me a good indication of the hull weight.

Cheers

Damien

[Alan]

Damien,
looks pretty good to me, it might even out side to side when it's more level but the total should still be the same. When I weighed my 17'6" bond wood it was almost the same at each corner (total 150kg without deck) You'll have to do a before and after. Anyway, 255 by 4 blokes is around low 60's bet they wouldn't complain if it was a blonde.

Alan.