Replacement gates at Benson Lock

Captain Coochie

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I'm interested in why they have swapped them for steel . Seems odd to me as timber gates are easier to repair . Well i think they are and thats why they have been used for the last x amount of years . This lock was 1890's and had timber gates for all that time without all this work done so why change the materials ?
I know nothing about steel or lock construction come to think of it . I'm just interested in the reasons .
 

TrueBlue

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I'm interested in why they have swapped them for steel . Seems odd to me as timber gates are easier to repair . Well i think they are and thats why they have been used for the last x amount of years . This lock was 1890's and had timber gates for all that time without all this work done so why change the materials ?
I know nothing about steel or lock construction come to think of it . I'm just interested in the reasons .

Be patient Cuchie, I've prepared a long article explaining succinctly (I don't do "succinct" as folks here know) some of the ins and outs.
Too long (see above) for this forum so it'll appear over on TMBA when I've solved layout and piccies problems.
 

teddington_lock

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As i understand it , it is to do with the procurement of hardwood timber for the gates.

The frames are greenheart , with oak planking.

Sourcing it from a sustainable place is nigh on impossible. So they are made in steel.

Chertsey lock has had steel gates for years , Boveney too.

Our gates on head and tail of the launch lock are steel , the middle gates of the barge lock are steel ( head and tail are wood though )
 

TrueBlue

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As i understand it , it is to do with the procurement of hardwood timber for the gates.

The frames are greenheart , with oak planking.

Sourcing it from a sustainable place is nigh on impossible. So they are made in steel.

Chertsey lock has had steel gates for years , Boveney too.

Our gates on head and tail of the launch lock are steel , the middle gates of the barge lock are steel ( head and tail are wood though )

Paul Power said as much in his presentation. New gates are lifted / inspected every 15 years and I suspect that cleaning up the rough bits on these will be easier than resheeting the old timber gates.
I got the impression that all replacements in future will be steel.

The exception is Iffley which being in a heritage area has to be timber...
Daft - you can't see the gate from anywhere and the walkways are already steel, completely masking any nice woodwork...

Bummer.
 

Captain Coochie

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Its odd that the main reason given seems to be you just cant get good wood anymore or its hard to find .
That just isnt true .
Will they really last that much longer considering that timber gates can be repair in place given them a longer life .
I'm not really fussed about it as i said . I just think that its odd to change the construction after hundreds of years .
I would be interested in the timber sizes needed to construct a lock gate so i can work out how much one costs . Green timber aswell i assume so even cheaper .
 

dash300

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I'm interested in why they have swapped them for steel . Seems odd to me as timber gates are easier to repair . Well i think they are and thats why they have been used for the last x amount of years . This lock was 1890's and had timber gates for all that time without all this work done so why change the materials ?
I know nothing about steel or lock construction come to think of it . I'm just interested in the reasons .

Steel gates are certainly more common on the continent than wooden ones and many of their locks are vast and deep. If your in the bottom of one of their deep ones on a sunny day its like being in a fridge! I can only assume that steel is stronger and more easily repaired than our beautifully crafted wooden ones. The major continental routes are still very much driven by commercial traffic than leisure and commercials have priority at the locks.
Having shared locks with fuel barges for Skippol airport who used me as a fender:eek: I am quite happy to let them go first.
 

TrueBlue

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Its odd that the main reason given seems to be you just cant get good wood anymore or its hard to find .That just isnt true .
Will they really last that much longer considering that timber gates can be repair in place given them a longer life .
I'm not really fussed about it as i said . I just think that its odd to change the construction after hundreds of years .
I would be interested in the timber sizes needed to construct a lock gate so i can work out how much one costs . Green timber aswell i assume so even cheaper .

Sorry, it was my spin on the topic (old goon show joke). PP did mention greenheart as a material.
That's go me thinking; on the narrow canals most lock gates are timber and those that are steel just rot away. Even steel balance beams are being replaced with good old timber. However, that's not necessarily true for broad locks.

On the upper, upper Thames when those huge balance beams 20' x 10" x 10" (guess) are replaced the replacements don't seem to be wearing well.

It may well be that it's more a case of can't get the wood in the right dimensions..

Could be an interesting topic. I think the price per gate was about £30k. Should have gone with a notebook.
 

Captain Coochie

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Well i can get you a whole tree if you want it so not being able to get it the right size may be something to do with where they are shopping or who they are ordering from .
I guess at one point the EA had thier own joinery shop . Do they still have one now ?
Maybe we will start seeing UPVC lock gates soon :D
 

teddington_lock

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It's not that you can't get good timber , more that ( being the EA ) using hardwood from a non sustainable source is a no no. I imagine PP has a fairly good inventory of suppliers.

The beams on ours at least are 12 x 12 .

If you want to see a big steel lock gate , get yourself to Tedders on the 13th Feb , as our tail gates are being lifted off the launch lock ( they are 6.85 metres high x 4.5 metres wide and weigh 10 tons each ) They will be lifted off by the salvage barge and then the barge will be towed round the end of the island and into the barge lock ( Teddingtons are the only gates on the river that the barge cannot lift completely to drop them onto a pontoon ) . There is an 80 ton mobile crane coming to the lock to lift them from the salvage barge onto the pontoons to be towed to Sunbury.

The head gates of the barge lock were re-sheeted about 4 years ago ( as the beams were found to be in excellent condition , so they weren't replaced with steel ) , and the tail gates of the barge lock are being resheeted in the autumn of this year ( again the beams are in excellent repair , must be the quality of the lock keeper who looks after them ;) )
 
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TrueBlue

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Great - some numbers

It's not that you can't get good timber , more that ( being the EA ) using hardwood from a non sustainable source is a no no. I imagine PP has a fairly good inventory of suppliers.

The beams on ours at least are 12 x 12 .

If you want to see a big steel lock gate , get yourself to Tedders on the 13th Feb , as our tail gates are being lifted off the launch lock ( they are 6.85 metres high x 4.5 metres wide and weigh 10 tons each ) They will be lifted off by the salvage barge and then the barge will be towed round the end of the island and into the barge lock ( Teddingtons are the only gates on the river that the barge cannot lift completely to drop them onto a pontoon ) . There is an 80 ton mobile crane coming to the lock to lift them from the salvage barge onto the pontoons to be towed to Sunbury.

The head gates of the barge lock were re-sheeted about 4 years ago ( as the beams were found to be in excellent condition , so they weren't replaced with steel ) , and the tail gates of the barge lock are being resheeted in the autumn of this year ( again the beams are in excellent repair , must be the quality of the lock keeper who looks after them ;) )

in your dreams (ha ha).

Doubtless you will do / arrange for some piccies to your normal 'igh quality, innit.

13th. Feb seems a bit ominous.. Only an 80 ton crane - had to have a 120 tonner to get my boat out of the garden - oh, it was a bit heavier....

Could be fun.
 
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