Sunday, November 21, 2010

The oddities of Lee locks and how they keep you fit

One of the things I like about canals is the variation in lock architecture as you move around different parts of the system.  Paddle gear (the gubbins you use to raise and lower the sluices that fill and empty the lock) has a number of different regional designs.  They are generally easy to work out how to operate, but the ones on the upper Lee Navigation caught me out all the time.  This is Rammey Marsh lock (note that the gates are opened by hydraulic rams).

The paddle gear is dead simple.  Look at it .  Just slide on the windlass and wind.  What's the problem?

Well let's look more closely at the one on the far side. Note the position of the ratchet.

It's identical (we're looking at the "back" of it of course).  I can feel you losing patience.  "What's so special about being identical?" you ask.    The answer is that they are normally made in matched pairs, one right handed and one left handed.  So when you stand ready to wind on a normal GU lock paddle you always swing the windlass from the top of the swing towards the lock to raise the paddle.  It's a habit that's hard to break when you've done a thousand of them.

But these on the Lee you always wind clockwise (or is it anti clockwise?) whichever side of the lock you are on.  It caught me out every time.  I'd end up straining and then realise I was pushing in the wrong direction.

Whilst I'm on the subject of Lee locks, there's one other feature I don't care for.  There is no way of crossing the top gates even when they are closed.  Imagine this, we are coming upstream and find a lock full (against us) and the top gates are left open.  Lee locks are big. Generally 90 feet long and 16 feet wide.  Let's say 36 paces long and 6 paces across the gates

I walk the length of the lock, 36 paces, and shut the first top gate.  I walk back 36 paces, across the bottom gate 6 paces and up to the other top gate 36 paces.  I shut the second gate.  I walk back 36 paces and open the bottom gate paddle, the 6 more paces over the gate to open the second paddle.  So far, that's 156 paces.  The lock empties and I open one gate.  Gates on the Lee are wider than normal so you really don't need both.

Kath brings in the boat and I close the gate and the paddle.  Then 6 paces over the gate to close the other bottom paddle.  36 more paces up to the top to open the first top paddle, then 78 more round to the other top paddle to open that. Now were up to 276 paces.

The lock fills.  I open the top gate and close the paddle.  Then 78 more paces round to close the other paddle.  That's 354 so far.  It's likely now that I have to do yet another 60 to get back to the boat on the other side before we leave.  So we have a total of 414 paces which is about double of what you would have to do on locks where you can cross the top gates.  Luckily the convention on the Lee is to leave gates open so we don't have to stay behind and close up after the boat.

One guy we saw last time we were up there had learnt the trick of running across the unguarded  top gate beams, but rather him than me.

It keeps you fit, this boating.

2 comments:

Halfie said...

How is it I never knew that about the paddles on the GU? I often find myself trying the wrong way first, unless I look at it and work out which way to wind. As you might imagine, I didn't have any more (or less) difficulty on the Lee! I'd rather have direct-acting paddle gear than hydraulic, anyway. Those manual hydraulic systems - paddles and gates - on the Lee are swines. I found the top gates wide enough to walk over, but I did it only when the lock was full.

VallyP said...

I've really enjoyed catching up with these last few posts, Neil. The gently wry humour of your writing is a pleasure to read. And I learn a lot too!