Revolving Bollards

[blackrose]

Does anyone know how you're supposed to use revolving bollards?

 

I came across my first one at Brentford gauging locks. I was going up from the Thames, and as the bollard was conveniently located in the centre of the lock close to the BWB key operated control panel and I was on my own, I used it with my centre rope putting a couple of loops around it.

 

What I didn't realise was that unlike a standard fixed bollard, as soon as the water came into the lock the bollard revolved backwards with the strain, unwinding the rope. There was no way that I could hold the boat on it and as I leant back in an attempt to slow the boat's progress to the other side of the lock, the top loop of rope came off the bollard & I fell backwards landing on my hand & spraining my thumb - much to the amusement of some local chavs.

 

Was I meant to lock the rope on itself around the bollard? If so then what is the point of the bollard being allowed to spin?

 

There are several of this type of bollard at these locks & I'd like to know how to use them properly as I'll be using these locks again & there isn't a fixed bollard I can use when I'm on my own with a centre rope. I can see they might work going down but you ultimately want to have control of the boat and these things just let the boat go where it wants!

Edited June 20, 2006 by blackrose

[GUMPY]

They are not bollards but pulleys. They were used for assisting the barges out of the lock by giving a double purchase.

There may have been an engine there which used them but it went before my time so I cant say for definate.

J

[blackrose]

They are not bollards but pulleys. They were used for assisting the barges out of the lock by giving a double purchase.

There may have been an engine there which used them but it went before my time so I cant say for definate.

J

 

So I shouldn't be using them at all?

[GUMPY]

So I shouldn't be using them at all?

 

Well I dont, but then the gauging lock is quite gentle and Parglena tends to just sit there when its filling.

 

J

[blackrose]

Well I dont, but then the gauging lock is quite gentle and Parglena tends to just sit there when its filling.

 

J

 

I was holding the boat on the centre island side which seemed logical as I was on my own & that's where the controls are, but as soon as I started filling the lock the boat wanted to go to the other side. Next time I'll put a rope round the bannister for the stairs!

[Richard Bustens]

If you had put the rope round it the other way would it not have shortened it so as to keep the boat in the side, helping you?

[blackrose]

If you had put the rope round it the other way would it not have shortened it so as to keep the boat in the side, helping you?

 

It doesn't matter which way round you put the rope, they spin both ways freely.

[Richard Bustens]

Sorry i thought you ment when the water came in the lock it turned the bollard one way and when it went out it turned it the other way.

[gralyn]

I Next time I'll put a rope round the bannister for the stairs!

 

That could be worse, as they are not designed to take the strain a boats weight. I have seen them pulled out of their ground anchorage when missused in this way.

[Speedwell]

It doesn't matter which way round you put the rope, they spin both ways freely.

I would suggest that you loop the rope round the bollard and then round itself as many times as is necessary to get the degree of friction that you need.

Arthur

[blackrose]

That could be worse, as they are not designed to take the strain a boats weight. I have seen them pulled out of their ground anchorage when missused in this way.

 

Ok, point taken!

 

Sorry i thought you ment when the water came in the lock it turned the bollard one way and when it went out it turned it the other way.

 

No they aren't connected to anything - just bollards (sorry pulleys) that move!

 

I would suggest that you loop the rope round the bollard and then round itself as many times as is necessary to get the degree of friction that you need.

Arthur

 

Thanks, I'll try that.

[DHutch]

I would suggest that you loop the rope round the bollard and then round itself as many times as is necessary to get the degree of friction that you need.

Yeah, thats one way of doing it.

- Otherwise, you could loop the rope round the bollard/pulley thing, and back onto the boat, and use the boat fittings to generate the required friction. Depending on the suitablity of the boats fittings for this.

 

Alteratativly you can wrap the rope around the ballance beams of the lock.

 

 

Daniel

[Hairy-Neil]

 

 

Alteratativly you can wrap the rope around the ballance beams of the lock.

Daniel

 

Brentford Guaging Locks have no balance beams.....

[DHutch]

Brentford Guaging Locks have no balance beams.....

Yeah well, theres always one...