How much do my mast weight.

sailaboutvic

sailaboutvic

Well-Known Member
Joined
26 Jan 2004
Messages
9,972
Location
Northern Europe
Visit site
Here a question for the number crunchers .
Removing a 14 mts mast off my boat how much less daft would I have ?

We Draw 1.85 Mts in salt water , just doing some sums and wonder about doing some of this season plotting about in the French rivers and canals has we be sailing the south of France .
 
We need a lot more information than that. Material for a start. Where are your going to keep it as you wander about the rivers? Where will your sails go?

Given to people can lift my my mast and all the gubbins that come with it lets say 100 KG. When somebody steps onboard I cant see any change in the waterline.
 
Mast Aluminum , storing it isn't a problem there mast racks in port Napoleon .
Also being in fresh water it would float higher .
Need to knock off 20cm at less
 
Last edited:
Vic,
Fresh water is less dense (less buoyant) than seawater so you would need to displace more freshwater to achieve the same buoyancy meaning you actually float lower in fresh water!! The difference is about 25kg per tonne - so if you remove 250kg mass from a 10tonne boat and put it in freshwater the waterline will stay the same.
Chances are that when you remove mast, rigging, sails etc and move to fresh water your waterline level will be much the same
 
crisjones said:
Vic,
Fresh water is less dense (less buoyant) than seawater so you would need to displace more freshwater to achieve the same buoyancy meaning you actually float lower in fresh water!! The difference is about 25kg per tonne - so if you remove 250kg mass from a 10tonne boat and put it in freshwater the waterline will stay the same.
Chances are that when you remove mast, rigging, sails etc and move to fresh water your waterline level will be much the same
Click to expand...

Thanks Chris , look like we be spending more time sailing the south French coast .
I take it your doing the crossing this year ?
 
You will lose very little draught by taking off an alloy mast, probably under a centimetre. You will gain more than that in draught by going from salt to fresh water - maybe 4 to 6 cm. You will draw MORE THAN 1.85 in fresh water, even with mast off.
 
You might find that removing many layers of old antifouling, call it copper, might have more impact. I doubt it will give you 20cm. But - emptier water tanks, no mast (boom plus pole), less chain, a clean hull, gen set? no sails might all add up.

Jonathan

edit

And then think like a racing yacht, or multihull - what else do you not need (at all) or might do without (for a few week, month).
 
Last edited:
Neeves said:
You might find that removing many layers of old antifouling, call it copper, might have more impact. I doubt it will give you 20cm. But - emptier water tanks, no mast (boom plus pole), less chain, a clean hull, gen set? no sails might all add up.

Jonathan



edit

And then think like a racing yacht, or multihull - what else do you not need (at all) or might do without (for a few week, month).
Click to expand...

Removing antifoul layers is an interesting idea in that I think it may well make things worse given the density of spent dry antifoul and the fact it's under water. I think it might actually be contributing to buoyancy. Based on nothing other than a hunch.
 
Neeves said:
You might find that removing many layers of old antifouling, call it copper, might have more impact. I doubt it will give you 20cm. But - emptier water tanks, no mast (boom plus pole), less chain, a clean hull, gen set? no sails might all add up.

Jonathan

edit

And then think like a racing yacht, or multihull - what else do you not need (at all) or might do without (for a few week, month).
Click to expand...
As full time liveaboard I guess there lots more we could remove :) .
Chris has set me straight , just a idea I had in a min of madness at 05.00 althought we could still spend some time doing the Rhone which should give us a few months doing some thing different .
 
It’s dead easy to work out. Measure its thickness, height and circumference in metres. Multiply all the dimensions, then by 2,600 to get kg. Add a bit for spreaders and wire and rope.

For the effect on displacement you need the x section area of your waterline. A tape measure and simple maths should get close enough.
 
Last edited:
If I read your question properly, you intend to leave the mast in Port Napoleon tootle inland a bit then return to Port Napoleon after tootling.

If that is correct you have no problem whatsoever. You have a a lot of water on the Rhone until Lyon, then take the Saone seamlessly which I also believe has sufficient depth. You can reach the very heart of France with no problem (look at the map for wine regions for instance) calling at many fine places, I reckon you could easily reach St Jean do lois (spelling) which I, quite cosy and cheap(ish) winter lay-up place for many lay-abouts.

Take a good buke or buy a moped in st Jean de whatnot.

Edit: I have included a few grammar mistakes to let you feel comtortable. OOoeeer gee whiz ---ducking and running. :;-) ;-) ;-(.
 
Last edited:
BurnitBlue said:
If I read your question properly, you intend to leave the mast in Port Napoleon tootle inland a bit then return to Port Napoleon after tootling.

If that is correct you have no problem whatsoever. You have a a lot of water on the Rhone until Lyon, then take the Saone seamlessly which I also believe has sufficient depth. You can reach the very heart of France with no problem (look at the map for wine regions for instance) calling at many fine places, I reckon you could easily reach St Jean do lois (spelling) which I, quite cosy and cheap(ish) winter lay-up place for many lay-abouts.

Take a good buke or buy a moped in st Jean de whatnot.

Edit: I have included a few grammar mistakes to let you feel comtortable. OOoeeer gee whiz ---ducking and running. :;-) ;-) ;-(.
Click to expand...
Hey hey hey :) your PC spell check has let you down again , haha .
Yes I have looked at it again to day between wiring up a new battery monitor and sitting in the sun enjoying a glass of vino .
The Rhone has about 350 miles of good navigation water and has you say then there the Saone should keep us busy for a while ,
In between a bit more work to morrow and my afternoon siesta more research to be done ,
If anyone done this it be good for your experience.
 
Don't the reeely keen racers snap their tooth brushes in half to reduce weight? Perhaps shave daily to get rid of heavy stubble?
Best stay away from the Canal di Midi on account of the depth..
 
Vic
Remember to factor in an allowance for all the cases of wine that you will persuade yourself to buy for the return journey.:very_drunk:
 
Resolution said:
Vic
Remember to factor in an allowance for all the cases of wine that you will persuade yourself to buy for the return journey.:very_drunk:
Click to expand...

Do you think I stupid or something ? ? .
That's all going in the dinghy which I plan to tow behind :) which will be towing another dinghy which will have anchor,chain,outboard,tools,fuel,water,food,all our worldly goods,locker, doors,floor boards, and me as I weigh more them my better half .
 
You must log in or register to reply here.

Share this page

Top