Weighing a dinghy on bathroom scales

[Greenheart]

Ever tried it? On the basis that my boat may not turn the corner on the first floor landing, I'm thinking I'll take the scales to the boat instead of bringing her home...

...but if I put each wheel in turn on the scales, then the point of the bow, and if I add up the results and subtract the weight of the trolley, is there any reason I won't have calculated what the boat weighs?

Mine isn't a very typical example of the Osprey class, so the textbook figures aren't likely to apply.

Thanks!

 

[penfold]

Take two pieces of wood the same depth as the scales, or stacks of pieces of wood to make up the depth, to prop up the wheel or bow where the scale isn't, or the weighing process will be inaccurate, or at least more inaccurate than it needs to be. Scales need to be as level as possible for best results so flat-ish concrete or tarmac is preferable to other surfaces; if not take a piece of plywood to go underneath and do your best.

 

[LittleSister]

Or borrow a couple more bathroom scales for an hour, and you won't need to worry about differential levels.

 

[Boater Sam]

Spring balance, raise one corner a little at a time. Add.

 

[Chiara’s slave]

Or borrow a couple more bathroom scales for an hour, and you won't need to worry about differential levels.

This way is good. Accurate, way better than one corner at a time. But I’d love to see the OP carry his Osprey to the bathroom.

 

[finestgreen]

Ever tried it? On the basis that my boat may not turn the corner on the first floor landing, I'm thinking I'll take the scales to the boat instead of bringing her home...

...but if I put each wheel in turn on the scales, then the point of the bow, and if I add up the results and subtract the weight of the trolley, is there any reason I won't have calculated what the boat weighs?

Mine isn't a very typical example of the Osprey class, so the textbook figures aren't likely to apply.

Thanks!

What about getting a handful of cheap luggage scales and lift the dinghy by them all at the same time? (Perhaps with the assistance of some volunteers)

 

[Daydream believer]

Most class assns have the gear to weigh the dinghies. Are you not a member of the Osprey class?
A club may have a set of dinghy scales & can stick the boat in a pair of slings & weigh it. That is what happens at our club at national events. Are you a club member?

 

[Daydream believer]

What about getting a handful of cheap luggage scales and lift the dinghy by them all at the same time? (Perhaps with the assistance of some volunteers)

I would imagine Dan's boat weighs as much as a 20ft cruiser. It would probably need a substantial diet for the average luggage scales. Do not forget he has half the planets supply of plastic bottles for buoyancy in the tanks (which are, by now, probably 25% full of water)& extra drain tubes for starters. Plus lots of -shall we say- additional experiments, to add weight.

 

[Refueler]

Get a hanging scale ... put rope round the dinghy and hoist it up .... scale will show immediately without any maths needed.

 

[Daydream believer]

..

Get a hanging scale ... put rope round the dinghy and hoist it up .... scale will show immediately without any maths needed.

So without a friendly YC, - Plus a point to hoist it from, complete with tackle-, any ideas where Dan would obtain such a set up?

 

[Refueler]

..

So without a friendly YC, - Plus a point to hoist it from, complete with tackle-, any ideas where Dan would obtain such a set up?

Given some of the other replies .....

 

[Boater Sam]

Weigh it like you do a dog. Weigh yourself, then carry boat and weigh again. Simple deduction will reveal the weight I trust,......or should that be truss?

 

[Chiara’s slave]

Picking up an Osprey, you’ll certainly need a truss afterwards.

 

[tico]

I learnt to sail in a 'Fish' which I understand was the prototype for the Osprey. (Sail number 5)
that took 4 people to lift it!

 

[Minerva]

I would imagine Dan's boat weighs as much as a 20ft cruiser. It would probably need a substantial diet for the average luggage scales. Do not forget he has half the planets supply of plastic bottles for buoyancy in the tanks (which are, by now, probably 25% full of water)& extra drain tubes for starters. Plus lots of -shall we say- additional experiments, to add weight.

Easy solution - fill the old coke bottles with helium - hey presto an osprey that floats in the air! Give those America's cup boats a run for their money who are reliant on foils for their upwards lift!

 

[Malabarista]

Go to your local commercial waste transfer station and drive onto the weighbridge. Go home. Take the dinghy off the trailer and go back to the weighbridge to get the weight of vehicle plus trailer. Hey presto. This is a bit topical for me as i am currently ( yeah really) sitting in the queue of a commercial waste transfer station ?

 

[Stemar]

Easy solution - fill the old coke bottles with helium - hey presto an osprey that floats in the air! Give those America's cup boats a run for their money who are reliant on foils for their upwards lift!

Be a bit of a bugger to manage close hauled, though - rather more leeway than you'd want

 

[fisherman]

We wanted to weigh a large hatch cover. We found a fulcrum, a beam, and a suitable (20kg in this case) weight. Hung the cover off one end, the weight off the other, shifted the weight until we had equilibrium, did the measurements and applied the ratios. The weight can be a container for water which is added and is easily quantified. Or you can use a person of known weight.

 

[Daydream believer]

We wanted to weigh a large hatch cover. We found a fulcrum, a beam, and a suitable (20kg in this case) weight. Hung the cover off one end, the weight off the other, shifted the weight until we had equilibrium, did the measurements and applied the ratios. The weight can be a container for water which is added and is easily quantified. Or you can use a person of known weight.

That better not be the wife then, or your figs will be well out. Might be a bit dodgy if she sees the calculations that you apply .

 

[Daydream believer]

. This is a bit topical for me as i am currently ( yeah really) sitting in the queue of a commercial waste transfer station ?

What bin will you be getting in to?