For those who bought a widebeam - regrets? or still happy?

[Robbo]

Thanks. It's not bad for a basic Liverpool Boat, but it really could do with a paint job now.

 

And you've moved the oil radiator from the middle of the room, looks a lot better now

[MtB]

 

And you've moved the oil radiator from the middle of the room, looks a lot better now

 

And given it's a bloke's boat, I'm wondering why a living room that size isn't full of engine parts, motorbike frames, circular saws, oil drums, dozens of PCs, all that sort of stuff, y'know...

 

 

MtB

[mark99]

 

And given it's a bloke's boat, I'm wondering why a living room that size isn't full of engine parts, motorbike frames, circular saws, oil drums, dozens of PCs, all that sort of stuff, y'know...

 

 

MtB

 

And a Stirling Engine. Plus an empty coffee jar with a old paintbrush in it.

Edited October 22, 2014 by mark99

[MtB]

 

And a Stirling Engine. Plus an empty coffee jar with a old paintbrush in it.

 

 

Ah yes!

 

And of course a workbench made from a pair of trestles and an old door, covered in clutter...

 

 

 

MtB

[blackrose]

 

And given it's a bloke's boat, I'm wondering why a living room that size isn't full of engine parts, motorbike frames, circular saws, oil drums, dozens of PCs, all that sort of stuff, y'know...

 

 

MtB

Because all that crap is cluttering up my engine hole!

[Scholar Gypsy]

 

Yes nice and simply explained.

 

It's not intuitive but correct.

 

It catches people out who go to great lengths to try to rubbish the fact that the same water is needed to transit a lock whatever boat size is used.

 

When going up, less water goes into the lock chamber via the paddles but lots go in via the top gates when they are opened and the boat moves out.

 

Now re widebeams. I would not rule out a widebeam but if we did get one it would be a shapely classic like a proper Dutch Barge. I've seen some lovely wide boats on the GU but they are all old classics.

 

Sorry, but it's not correct. Going through or transitting a lock involves three steps:

 

a) putting the boat into the lock

b ) raising or lowering the boat once it is in the lock

c) leaving the lock

 

Many of the earlier posts on this subject focus just on step b ), which always uses the same volume of water - the size of the lock (width x length x rise) = V, and is not affected by the size of the boat.

 

However a) and c) depend on the displacment (weight) of the boat = D

 

And so the net effect is that the amount of water used when transiting a lock is V+D when travelling uphill, and V-D when travelling downhill.

Edited October 22, 2014 by Scholar Gypsy

[kazbluesky]

 

You have a lovely boat BlackRose

 

 

Wow that is a big boat, beautiful too. Thanks for the info.

[Robbo]

 

Sorry, but it's not correct. Going through or transitting a lock involves three steps:

 

a) putting the boat into the lock

b ) raising or lowering the boat once it is in the lock

c) leaving the lock

 

Many of the earlier posts on this subject focus just on step b ), which always uses the same volume of water - the size of the lock (width x length x rise) = V, and is not affected by the size of the boat.

 

However a) and c) depend on the displacment (weight) of the boat = D

 

And so the net effect is that the amount of water used when transiting a lock is V+D when travelling uphill, and V-D when travelling downhill.

 

Thats how I thought (see post 23 or 24), however the water in steps a and b is not actually used so is not lost in the process of using the lock.

[kazbluesky]

I tried to copy your pics to this post but couldn't manage it somehow. How long did it take you to fit out Black Rose? You did it yourself, yes? Did you have any previous experience with fitting out a boat?

[mark99]

 

Sorry, but it's not correct. Going through or transitting a lock involves three steps:

 

a) putting the boat into the lock

b ) raising or lowering the boat once it is in the lock

c) leaving the lock

 

Many of the earlier posts on this subject focus just on step b ), which always uses the same volume of water - the size of the lock (width x length x rise) = V, and is not affected by the size of the boat.

 

However a) and c) depend on the displacment (weight) of the boat = D

 

And so the net effect is that the amount of water used when transiting a lock is V+D when travelling uphill, and V-D when travelling downhill.

 

Too many beers last night.

 

Step B - yes - same water used - clumsy words by me.

 

Critique / try this as an explanation re step B re going down?

 

As well as water volume around the boat from upper lock height to lower lock height, water volume from the 3d shape of the boat under the waterline is forced out of paddles (eg when going out downhill) but this extra water slips back in when transitting.

Edited October 22, 2014 by mark99

[Robbo]

 

Too many beers last night.

 

Step B - yes - same water used - clumsy words by me.

 

Critique / try this as an explanation re step B re going down?

 

As well as water volume around the boat from upper lock height to lower lock height, water volume from the 3d shape of the boat under the waterline is forced out of paddles (eg when going out downhill) but this extra water slips back in when transitting.

Water isn't forced out, it's all done by gravity.

[mark99]

Water isn't forced out, it's all done by gravity.

 

 

Ok yes but is that a simple explanaion of why the same water is used?

 

as the boat falls in the lock the submerged bit of the boat pushes up water (displaces) and that water exits the paddles

Edited October 22, 2014 by mark99

[Robbo]

 

 

Ok yes but is that a simple explanaion of why the same water is used?

 

as the boat falls in the lock the submerged bit of the boat pushes up water (displaces) and that water exits the paddles

I don't really understand what your trying to say. As long as the two are connected at or below the lower water level, the lock will "empty" or "fill" once you've removed the paddle(s). Like having two water tanks connected together at the bottom, they will both find the same level. Edited October 22, 2014 by Robbo

[MtB]

Because all that crap is cluttering up my engine hole!

 

 

Ah but a widebeam as big as yours doesn't have an 'engine ole', it has an 'engine cavern' surely!

 

 

MtB

[Scholar Gypsy]

 

Thats how I thought (see post 23 or 24), however the water in steps a and b is not actually used so is not lost in the process of using the lock.

 

Here's another way of looking at this, that gets the same answer.

 

On a level stretch of water when a boat moves from A to B then an equal volume of water moves from B to A -to fill the "hole" left at A. That amount of water is D, the displacement.

 

This result holds true even if the boat pauses half way between A and B, to go up or down in a lock, of volume V. The amount of water needed, once the boat is n the lock, to raise (or lower) the level of water in the lock is V - not affected by the size of the boat.

 

So, combining both results, if you go down a lock (and leaving it as you found it), the amount of water that moves from the top pound to the lower pound is V-D (as the water in the "hole" below the lock "moves" to the hole above the lock). If you go up the amount of water that moves from the upper pound to the lower pound is V+D.

[mark99]

I don't really understand what your trying to say. As long as the two are connected at or below the lower water level, the lock will "empty" or "fill" once you've removed the paddle(s). Like having two water tanks connected together at the bottom, they will both find the same level.

 

Trying to communicate why it's wrong when people think a big boat uses more water than a little boat using the lock by using a simple explanation. Still I'll leave it.

Edited October 22, 2014 by mark99

[mark99]

 

 

 

This result holds true even if the boat pauses half way between A and B, to go up or down in a lock, of volume V. The amount of water needed, once the boat is n the lock, to raise (or lower) the level of water in the lock is V - not affected by the size of the boat.

 

So, combining both results, if you go down a lock (and leaving it as you found it), the amount of water that moves from the top pound to the lower pound is V-D (as the water in the "hole" below the lock "moves" to the hole above the lock). If you go up the amount of water that moves from the upper pound to the lower pound is V+D.

 

The trouble with that is that someone may say (erroneously)

 

"but my little d is not as big and your big D hence I've used less water in the lock!"

 

Also I'm still unsure about your saying it take different volumes of water to lift or descend any boat - so bear with me.

 

Going Down

 

1) The lock takes 100 tonnes of water from empty to full. The lock is full. A 35 tonne boat enters top gate and pushes out 35 tonnes water back into upper pound. The top gate is closed. You let 65 tonnes water out of the lower paddles, now after 65 tonnes water have been let out, the boat pushes up 35 tonnes of water to maintain being afloat, this water escapes through the paddles as normal. Total water let through paddle = 100 tonnes.

 

Going UP

 

The lock is empty and the lower gates open. A 35 tonne boat moves in and 35 tonnes water moves out but the lower water level, of course, remains the same. The lower gates are closed. Upper paddles are opened and 100 tonnes of water are needed to fill lock from lower level to upper level before you open lock gates and move out.

 

NB are you saying if you left a boat in a lock and just opened and closed the paddles going up then down, the water used is different?

Edited October 22, 2014 by mark99

[blackrose]

I tried to copy your pics to this post but couldn't manage it somehow. How long did it take you to fit out Black Rose? You did it yourself, yes? Did you have any previous experience with fitting out a boat?

 

It was built as a lined sailaway, so according to one p*ss-taking neighbour it was already fitted-out when I bought it and should never have taken me so long to finish. I have to admit he was right - it took me ages... But I was living on it while installing the stove, fitting the kitchen, bathroom, building cupboards, installing the gas system and fitting various bits of electrical equipment. Living on a boat while fitting it out is always going to be a bit slower - plus I didn't have any previous experience and never claimed to be quick.

 

But I think even inexperienced people can get reasonable results if they take their time and do plenty of research beforehand. I was always ok at using tools so that helped. If you look carefully every job I did is far from perfect, but I think the overall effect is good.

 

Galley at the stern

 

Corridor from the saloon through to the bedroom with the bathroom to the right

 

Cupboards I built to use the dead space along the corridor and into the bedroom.

 

 

Bedroom at the bow. I just bought some pine wardrobes and fitted them to the bulkhead. I couldn't afford oak to match the lining.

 

Trying to communicate why it's wrong when people think a big boat uses more water than a little boat using the lock by using a simple explanation. Still I'll leave it.

 

I haven't bothered to follow the various arguments on this subject because I'd first need someone to explain to me why it matters....

Edited October 22, 2014 by blackrose

[David Mack]

 

Thats how I thought (see post 23 or 24), however the water in steps a and b is not actually used so is not lost in the process of using the lock.

And this point is surely the nub of why people disagree whenever this topic comes up. There is no common definition if what is meant by water being "used".

 

To my mind water is not "used" if it merely swaps place with a boat as it enters or leaves a lock, as the water level does not change. I think there are only two valid definitions of "used" (in our perfect world where lock gates don't leak and evaporation doesn't occur etc.):

 

1. The amount of water "used" is that which has to be added to the top pound to bring it back to the same water level as at the start.

2. The amount of water "used" is the quantity which goes to waste over the overflow on the bottom pound (or lost to a river, the sea etc).

 

Over time these two quantities are equal, but for a single locking may differ e.g. if the lock starts out empty and ends up full.

 

The discussion here has only concerned the movement of boats, but on a freight carrying canal there is another effect. When a boat is loaded it sinks deeper into the canal and so some water is lost over the overflow (if the canal was already full). Similarly the water level drops when a boat is unloaded, and so needs to be topped up.

 

So here's a puzzle to ponder: A simple canal has two pounds and a single lock. A cargo is loaded on boats at one end of the canal and emptied at the other end, the boats returning empty to be reloaded. Does the canal use more water if the cargo is travelling uphill or downhill?

[Dalslandia]

many people have don the study on "The importance of water for shipping"

It's like talking about if a fly change the weight of an airplane if it fly around inside the cabin or sits on the back of a seat.

;-)

 

Have to ad, that many people don't understand, or just ask anyway to have something to say, how the water come back up the canal system? and if the water freeze in winter? and ask if it is a summer job? and if we (a day trip tourist boat) goes in winter too? This is the 4 most common questions we get.

Edited October 22, 2014 by Dalslandia

[Scholar Gypsy]

Dear Mark

 

You said this - my suggested changes are below

 

 

The trouble with that is that someone may say (erroneously)

 

"but my little d is not as big and your big D hence I've used less water in the lock!"

 

Also I'm still unsure about your saying it take different volumes of water to lift or descend any boat - so bear with me.

 

Going Down

 

1) The lock takes 100 tonnes of water from empty to full. The lock is full. A 35 tonne boat enters top gate and pushes out 35 tonnes water back into upper pound. The top gate is closed. You let 65 tonnes water out of the lower paddles, now after 65 tonnes water have been let out, the boat pushes up 35 tonnes of water to maintain being afloat, this water escapes through the paddles as normal. Total water let through paddle = 100 tonnes.

 

Going UP

 

The lock is empty and the lower gates open. A 35 tonne boat moves in and 35 tonnes water moves out but the lower water level, of course, remains the same. The lower gates are closed. Upper paddles are opened and 100 tonnes of water are needed to fill lock from lower level to upper level before you open lock gates and move out.

 

NB are you saying if you left a boat in a lock and just opened and closed the paddles going up then down, the water used is different?

 

And my suggested changes ...

 

 

The trouble with that is that someone may say (erroneously)

 

"but my little d is not as big and your big D hence I've used less water in the lock!"

 

Also I'm still unsure about your saying it take different volumes of water to lift or descend any boat - so bear with me.

 

Going Down

 

1) The lock takes 100 tonnes of water from empty to full. The lock is full. A 35 tonne boat enters top gate and pushes out 35 tonnes water back into upper pound. The top gate is closed. You let 65 100 tonnes water out of the lower paddles, now after 65 100 tonnes water have been let out, the boat pushes up 35 tonnes of water to maintain being afloat, this water escapes through the paddles as normal. Total water let through paddle = 100 65 tonnes. [Add: if lock is refilled then the net amount taken out of the top pound is also 65 tonnes

 

Going UP

 

The lock is empty and the lower gates open. A 35 tonne boat moves in and 35 tonnes water moves out but the lower water level, of course, remains the same. The lower gates are closed. Upper paddles are opened and 100 tonnes of water are needed to fill lock from lower level to upper level before you open lock gates and move out. 35 more tonnes of water is taken out of the top pound when the boat exits. The lock is emptied and puts another 100 tonnes into the lower pound. Total amount moved from top pound to bottom pound is 135 tonnes

 

NB are you saying if you left a boat in a lock and just opened and closed the paddles going up then down, the water used is different? No. I need to think more carefully about what is happening in energy terms...

[Scholar Gypsy]

So here's a puzzle to ponder: A simple canal has two pounds and a single lock. A cargo is loaded on boats at one end of the canal and emptied at the other end, the boats returning empty to be reloaded. Does the canal use more water if the cargo is travelling uphill or downhill?

 

That's a nice puzzle. For simplicity, lets assume there are no overflow weirs (or the water levels are well below them!). Start with an empty boat at one end. It is then loaded, goes to the other end, is unloaded, and then returns to base, Then the lock is in the same state, and there is X less water in the top pound and X more in the bottom pound - that needs to be backpumped to put the system back in the same state.

 

The logic of my earlier posts means that X is more if the load is being moved uphill (V+L, where V is the lock volume and L is the weight/displacement of the load), compared to downhill (V-L). Again, thinking about energy means this must be the case - it takes energy to lift things uphill, and energy is released if things move downhill. Because this puzzle involves the boat moving in both directions through the lock, the displacement of the unladen boat (D) cancels out from the final answer.

[mark99]

No. I need to think more carefully about what is happening in energy terms...

 

 

 

 

Simon,

 

If you accepted 100 tonnes water used whether you go up or down you would not have to think about this as it would all fall into place. .

[Scholar Gypsy]

 

Simon,

 

If you accepted 100 tonnes water used whether you go up or down you would not have to think about this as it would all fall into place. .

 

What I meant to say was that (obviously) if you fill the lock and then empty it (whether it has a boat in it or not) then 100 tonnes of water moves in each case. The energy changes need a bit more thought - to check if the reduction in potential energy when you fill a lock is the same as the subsquent reduction when you empty it. In each case gravitational energy is converted to kinetic and then (as the turbulence dies down) heat energy.

[mark99]

Don't forget displacement (transfer of 35 tonnes of water from one point to another) is powered by an external souce (in my case a 2LW).