Centre lines

[WotEver]

12 hours ago, Johny London said:

I just need for them not to slide along when I pull at an angle, so if I can utilise the nearest bits (uprights?) between the rails and roof that would work a treat. Those are welded and look more substantial that the thing the centre line is currently tied to.

That's what I did. Tied the rope around the handrail where one of the vertical supports were. 

[Chewbacka]

10 hours ago, Richard10002 said:

My fairleads are screwed into the angle iron handrails with 3 screws. Any tension is either horizontal, and/or downwards, so the forces aren't really in a direction likely to rip them out?

On recent practice being lazy... there are lots of things we do these days that could be considered lazy when compared with what we used to do, like Googling, rather than nipping to the reference library, or emailing, rather than sending a letter, or using a GPS rather than using a paper based map.

Ive been using centre lines on seagoing boats for decades, and it was actually considered good seamanship, rather than lazy.

I agree that mooring with a roof mounted centre line for any length of time is not a good idea, as changing levels or passing boats can list the boat, possibly to dangerous angles.

Whilst the tension load is indeed horizontal it puts the fixing screws in shear, so it all depends on the screw diameter and material.  A quick google shows a steel m6 fully threaded bolt to have a shear strength of about 4kN - so about 400kg.  so with 3 bolts that would give you about a ton without much safety margin.  But this would only arise if the rope had a very shallow angle to the boat, which would happen if using for an emergency stop.  Of course if your bolts are m4 or m5 and brass then.................

[furnessvale]

11 hours ago, Neil2 said:

Using a centre line to stop the boat or as a temporary mooring is actually a fairly recent practice which only became common when steel topped narrowboats became the norm.  I admit I do it but I think it is a lazy way of handling a narrowboat. 

  

 

Working boats have had back end lines for generations and I see nothing lazy about using them.

George

 

[NB Esk]

This is the set up on my boat, I still have the conventional centre line but these are really useful and used a lot.  Slightly untidy at the mo as an anti theft line for a side fender shares the ring.

installed during the build, the ring eyes are screwed into a nut which is tack welded to the inside.  It's an ideal place for these as they sit in the recess and don't protrude.  As an added bonus the two lines are led back and hang down the end of the back cabin, acting as door stops.  The lines are not long enough to reach the prop if dropped in.

 

 

[Johny London]

I've attached my second centre line now. Fixed to the proper thing in the middle of the roof then tied through the rail where there is a decent sized vertical support welded from rail to roof. It certainly has made life easier.

Thanks.

[Phil Ambrose]

On ‎14‎/‎07‎/‎2017 at 17:41, Peter-Bullfinch said:

This is our arrangement using two centre lines and two cleats to help keep them away from the solar panels. For the last three years this has worked fine.....so far.

 

Cleats or Fairleads?

Phil 

[WotEver]

8 minutes ago, Phil Ambrose said:

Cleats or Fairleads?

Phil 

Well the picture appears to be of fairleads. 

[howardang]

56 minutes ago, WotEver said:

Well the picture appears to be of fairleads. 

Cleats are things to secure a rope to. Fairleads are something to allow a rope to have a "fair lead" (the clue is in the name.)

Fairlead

http://www.enarastore.top/index.php?main_page=product_info&products_id=12119

Cleat

https://www.dockbuilders.com/dock-cleats.htm

The picture shows fairleads.

 

Howard

Edited August 14, 2017 by howardang

[Peter-Bullfinch]

Agreed....they are fairleads.  Now we only have one! The other was scraped off by the valve failing on the lift bridge at the end of the Pontcysyllte Aqueduct as we went under.  It was thankfully repaired fairly promptly....the bridge winding mechanism....not my fairlead...yet.

[Patrick_C]

Having switched from a single to a pair of centre lines recently because of the line snagging on things on the roof and I fitted fairleads. As I have tubular running rails and kept losing the lines over the sides) also fitted cam cleats (used on yachts) to clip them in place . You can release and reclip the line with one hand which is handy when you come in to moor and want to hop off the back. The biggest ones of these will take a 8 or 10 mm line.

 

 

[howardang]

1 hour ago, Patrick_C said:

Having switched from a single to a pair of centre lines recently because of the line snagging on things on the roof and I fitted fairleads. As I have tubular running rails and kept losing the lines over the sides) also fitted cam cleats (used on yachts) to clip them in place . You can release and reclip the line with one hand which is handy when you come in to moor and want to hop off the back. The biggest ones of these will take a 8 or 10 mm line.

 

 

Jamming cleats (or cam cleats) like the ones you picture are fine in the context they are mainly used for on sailing yachts,  but as you mention there is a limiting size which precludes many sizes of rope used on canal craft which can be 12-16mm.

Another issue with them on canals is that they are fine if the pull on the rope is horizontal or below horizontal, so that that rope stays jammed in the cleat, but if the pull goes above the horizontal then there is a danger of the rope pulling out, which could be a serious issue.

Howard

[Patrick_C]

23 minutes ago, howardang said:

Jamming cleats (or cam cleats) like the ones you picture are fine in the context they are mainly used for on sailing yachts,  but as you mention there is a limiting size which precludes many sizes of rope used on canal craft which can be 12-16mm.

Another issue with them on canals is that they are fine if the pull on the rope is horizontal or below horizontal, so that that rope stays jammed in the cleat, but if the pull goes above the horizontal then there is a danger of the rope pulling out, which could be a serious issue.

Howard

As the centrelines are indeed horizontal on the roof they are fine and have never come astray, and the fact you can whip them out upwards easily means they are ideal for single handed mooring situations.

[Richard10002]

If the cam cleats are merely to hold the centre lines in place on the roof, when not in use, I can't imagine an occasion when their coming free would be an issue, even if there was an unexpected upward pull.

[howardang]

6 minutes ago, Richard10002 said:

If the cam cleats are merely to hold the centre lines in place on the roof, when not in use, I can't imagine an occasion when their coming free would be an issue, even if there was an unexpected upward pull.

My concern was that some boaters may not be aware of their limitations and decide to use them inappropriately. 

Howard