Locks, another thought

[magpie patrick]

It's not supposed to be sacrificial in that sense, it's supposed to give slightly to mate when a steel edge wouldn't do that (on the Warwickshire Avon they have round mitre posts but I'm not sure how well that works if something gets caught in it.

 

Also, whilst there is a pre-disposition towards this wear on broad locks used by narrow boats, it can't be the only way it happens as it sometimes occurs on narrow locks as well, and I've seen old pictures of locks leaking like this when pairs were in common use and both gates would have been opened. I suspect gates that don't quite open properly are as prone, if not more so

[ditchcrawler]

It's not supposed to be sacrificial in that sense, it's supposed to give slightly to mate when a steel edge wouldn't do that (on the Warwickshire Avon they have round mitre posts but I'm not sure how well that works if something gets caught in it.

 

Also, whilst there is a pre-disposition towards this wear on broad locks used by narrow boats, it can't be the only way it happens as it sometimes occurs on narrow locks as well, and I've seen old pictures of locks leaking like this when pairs were in common use and both gates would have been opened. I suspect gates that don't quite open properly are as prone, if not more so

Its all those bloody canoeists

[Jerra]

I have just been reading NABO News about locks done the other way, Steel composite locks with sacrificial wooden edges that can easily be changed. I must say they did look good in the photos.

I was wondering if in this modern age there wasn't something which might deform when hit and then return to the original shape - rubber perhaps.

[ditchcrawler]

I was wondering if in this modern age there wasn't something which might deform when hit and then return to the original shape - rubber perhaps.

Maybe if fenders were attached properly they wouldn't lift gates out

[magpie patrick]

I was wondering if in this modern age there wasn't something which might deform when hit and then return to the original shape - rubber perhaps.

 

Some BCN single gates do have a rubber seal and they are spookily watertight - not a dribble

 

However, on a mitre gate I suspect it could get caught by a passing boat and pulled off, even on a narrow lock. On a single gate the seal is well out of the way when the gate is open, on a mite gate the boat can (and does) touch it

[Pluto]

Wide locks used to have slapping posts which the balance beam would hit when the gates closed, ensuring that the mitre faces fitted together correctly, ie with the flat faces flush against each other. The posts seem to have been removed in the 1960s, I was told because someone was killed after getting caught between the post and beam. Removing the posts allows the mitre to become rounded and more liable to leak because, as wooden gates twist slightly, the mitre does not fit in the same position each time the gates are closed. The photo also shows the bar under the beam which could be used to hold the gate open or closed, another lock fitting which has virtually disappeared. As Magpie mentions, it is difficult to fit a rubber seal which is not damaged by narrow boats entering or leaving wide locks. It has been tried.

 

[GUMPY]

 

The signs should say "to save water going all over the towpath" but they aren't long enough

That as you know is because BW rebuilt the bottom gates to tall.... same as lock59 on the GU.

 

For those that don't know the lock is the bywash as well, the top of the bottom gate and the weir in the top paddle chamber is what sets the level of the pound above, both should be the same height. So if the higher pound is up then the water goes down through the paddle chamber, fills the lock, then weirs over the bottom gates. This is common on the lower GU and K&A both of which are river fed. If you raise the height of the bottom gate the water can go over the towpath instead.

Also just because you come to a lock that is full when all the others have been empty its not always a sign that the top gates leak.

[spadefoot]

I was wondering if in this modern age there wasn't something which might deform when hit and then return to the original shape - rubber perhaps.

Whatever gets used, it will wear to some extent & therefore end up in the waterway, even at a microscopic level, & consequently in the flora & fauna of that waterway. With some waterways, that means it ends up in us.

It's possibly a minor thing, but I expect it has to be taken into account.

[MtB]

Wide locks used to have slapping posts which the balance beam would hit when the gates closed, ensuring that the mitre faces fitted together correctly, ie with the flat faces flush against each other. The posts seem to have been removed in the 1960s, I was told because someone was killed after getting caught between the post and beam. Removing the posts allows the mitre to become rounded and more liable to leak because, as wooden gates twist slightly, the mitre does not fit in the same position each time the gates are closed. The photo also shows the bar under the beam which could be used to hold the gate open or closed, another lock fitting which has virtually disappeared. As Magpie mentions, it is difficult to fit a rubber seal which is not damaged by narrow boats entering or leaving wide locks. It has been tried.

 

 

 

Interesting pic.

 

In addition to the slapping post, there appears to be a bar fixed to the underside of the balance beam with an eye bolt. They've all gone too nowadays. What were they for?

[Drayke]

 

 

Interesting pic.

 

In addition to the slapping post, there appears to be a bar fixed to the underside of the balance beam with an eye bolt. They've all gone too nowadays. What were they for?

The photo also shows the bar under the beam which could be used to hold the gate open or closed,

[MtB]

The photo also shows the bar under the beam which could be used to hold the gate open or closed,

 

Ah I see! Good idea.

 

Many thanks...

[Jerra]

 

 

Interesting pic.

 

In addition to the slapping post, there appears to be a bar fixed to the underside of the balance beam with an eye bolt. They've all gone too nowadays. What were they for?

I have seen some recently fitted but can't remember where. I seem to remember a thread decrying them and saying it was because current workers couldn't balance the gates properly.

[ditchcrawler]

I have seen some recently fitted but can't remember where. I seem to remember a thread decrying them and saying it was because current workers couldn't balance the gates properly.

T&M fradley

[gazza]

 

Ah I see! Good idea.

 

Many thanks...

Similar things can be found on handy lockside trees on the Nene, the vee gates are interlocked with the guillotine gate, if the vee gates open when you are trying to empty the lock the gate won't raise.

 

Nightmare on your own as you are 80' away and sods law says by the time you get back to the panel the vee gate swings open again.

Proping a bit of tree under the beam solves the issue.

[1st ade]

It's not supposed to be sacrificial in that sense, it's supposed to give slightly to mate when a steel edge wouldn't do that...

 

At Marple a year or two ago the maintenance guys were demonstrating how they made the wood fit.

 

Bolt it in place, apply paint to the leading edge and close the gate. Where the paint had been squashed out the way was a high spot, plane it down a bit and repeat. After three or four goes the wood had the profile of what it closed against whether that was the opposite mitre (bottom) or stonework (top).

 

Obviously all done with the lock completely drained.