Anchor light project - What rope for running a wire down?

[Minerva]

So on the back the anchor light thread and in particular the Tom Cunilife linked video around the traditional Paraffin riding light; I’ve gone and bought an antique brass oil lamp with fresnel lens that I’m pretty sure will be older than my late grandfather. It’s just arrived today and is quite the thing of beauty with a nice aged patina

I have no intention to have it lit by oil and have a 450lumen LED light also in the post and associated wiring*. This will go via a deck socket back to the switch board for the anchor light switch.

Question I’ve got just now, I will want to run the power cable down from the light to a to-be-installed socket. I think I’d prefer this to run inside the down haul rope.

I know I could probably achieve this with SK75 dyneema, but that feels out of keeping a bit with the feel of the light.

What other rope could I use that could hide a power cable? Cable will obviously only be a few mm in diameter, the rope only need to be 2ish meters long.

Thanks

*I fully appreciate this project makes no financial sense when a £20 Amazon light would serve just as well.

 

[Plum]

So on the back the anchor light thread and in particular the Tom Cunilife linked video around the traditional Paraffin riding light; I’ve gone and bought an antique brass oil lamp with fresnel lens that I’m pretty sure will be older than my late grandfather. It’s just arrived today and is quite the thing of beauty with a nice aged patina

I have no intention to have it lit by oil and have a 450lumen LED light also in the post and associated wiring*. This will go via a deck socket back to the switch board for the anchor light switch.

Question I’ve got just now, I will want to run the power cable down from the light to a to-be-installed socket. I think I’d prefer this to run inside the down haul rope.

I know I could probably achieve this with SK75 dyneema, but that feels out of keeping a bit with the feel of the light.

What other rope could I use that could hide a power cable? Cable will obviously only be a few mm in diameter, the rope only need to be 2ish meters long.

Thanks

*I fully appreciate this project makes no financial sense when a £20 Amazon light would serve just as well.

it is possible to run a cable down the centre of a traditional 3-strand line. Keep the ends whipped or heat sealed, twist the rope to loosen the three strands and wind the cable spirally down the rope between two of the three strands and work it in until it forms a central core withing the three stands. You will probable have to use a line diameter bigger than you wanted

www.solocoastalsailing.co.uk

 

[AntarcticPilot]

If your installing an LED, why not power it from rechargeable batteries? The oil tank must be big enough to hold a night's worth of power. 450 lumen bulbs appear to draw around 4 watts. At 12v that's a third of an amp-hour every hour, so 12 hours operation would require about 4Ah capacity. 6 batteries like this should be enough; 9 would give a good margin. Of course you'd have to charge the batteries before each use.

Of course, the exact voltage requirements of the led bulb will change the way the batteries are connected to obtain the right voltage, but the number of batteries will be the same. For 12v you'd connect groups of 3 in series, and then 2 or 3 groups of 3 in parallel.

 

[PetiteFleur]

One question - 450 lumens seems a very bright anchor light and would use a lot of amps, presumably at 12v?

 

[Neeves]

You can buy modern braid on braid ropes made to look traditional, so they look like hemp - I guess some might have a dyneema core.

Buy the appropriate length, strip out the core (there are lots of uses for dyneema) replaced the core with an electric cable. Stripping off the cover is easy.

You have said the project makes no financial sense . But the core you strip out you can use to make a Barber haul or........???

Jonathan

 

[Refueler]

You can buy modern braid on braid ropes made to look traditional, so they look like hemp - I guess some might have a dyneema core.

Buy the appropriate length, strip out the core (there are lots of uses for dyneema) replaced the core with an electric cable. Stripping off the cover is easy.

You have said the project makes no financial sense . But the core you strip out you can use to make a Barber haul or........???

Jonathan

That would be my suggestion also ... standard braid on core .. doesn't need to be braid on braid ... there are reasonable looking braid over strand ropes in DIY shops that its easy to remove the core strands ... in fact done carefully - the strands can pull the cable through ...

 

[Minerva]

Of course, the exact voltage requirements of the led bulb will change the way the batteries are connected to obtain the right voltage, but the number of batteries will be the same. For 12v you'd connect groups of 3 in series, and then 2 or 3 groups of 3 in parallel.

that was broadly my starting point too - have lithium cells in the base and a smart auto on/off sensor switch but then I need to also think about a charging circuit too. Suddenly is quite complex to a non electrical engineer such as myself.

I had thought about just buying and cannibalising an existing light, but that would always be a bit of a hodge podge and also…

I already have a good solar / mppt charged domestic battery bank that has more than enough juice. The lamp will need a downhaul made off to the region of the anchor locker anyway therefore Having a socket in the anchor well won’t have much more of a hassle when rigging.

Biggest nuisance will only adding in a switch by the mast to switch between mast head anchor light and swinging one and running a wire from there to anchor locker.

Plus with it being hard wired, when I get up in the morning and it’s horrible outside, I can just flick it off whilst still wearing my slippers and sipping my coffee.

 

[Minerva]

One question - 450 lumens seems a very bright anchor light and would use a lot of amps, presumably at 12v?

It promises to draw 5watts so power consumption should be negligible really . The lumen output is often exaggerated on bulbs so I’m presuming reality is half claimed output. So actually expect to get somewhere in the region of 200lumens

To meet 2mile visibility regs; it’s thought that 60ish lumens is what you’re after.

So these bulbs should be in excess of 2mile visibility, but not antisocial brightness - my trail running head torch is 2,000 lumens and that’s like having the sun strapped to your head. 200ish will be broadly equivalent to a normal head torch. what impact the fresnel lens has is a current unknown. I’m quite confident I won’t be mistaken for a lighthouse though!

 

[AntarcticPilot]

that was broadly my starting point too - have lithium cells in the base and a smart auto on/off sensor switch but then I need to also think about a charging circuit too. Suddenly is quite complex to a non electrical engineer such as myself.

I had thought about just buying and cannibalising an existing light, but that would always be a bit of a hodge podge and also…

I already have a good solar / mppt charged domestic battery bank that has more than enough juice. The lamp will need a downhaul made off to the region of the anchor locker anyway therefore Having a socket in the anchor well won’t have much more of a hassle when rigging.

Biggest nuisance will only adding in a switch by the mast to switch between mast head anchor light and swinging one and running a wire from there to anchor locker.

Plus with it being hard wired, when I get up in the morning and it’s horrible outside, I can just flick it off whilst still wearing my slippers and sipping my coffee.

Why build in the charging? The cells I linked to can be charged externally, so all you have in the lamp is effectively a battery box wired to give the correct voltage.

 

[Minerva]

Why build in the charging? The cells I linked to can be charged externally, so all you have in the lamp is effectively a battery box wired to give the correct voltage.

How would you charge them on board then?

 

[Refueler]

A bunch of 18650's making up the 12-13v with a plug / socket arrangement could easily be made up to be charged .....

There are cheap 2S / 3S chargers out there that run off 12v .... just plug in the battery charge lead ... no need to break the bank on this !!

 

[AntarcticPilot]

How would you charge them on board then?

Any of these: Lithium Battery Chargers | RS

 

[Minerva]

That’s worth a think. Thanks.

 

[Neeves]

That’s worth a think. Thanks.

whilst you are pondering

Most anchor lights are designed to simply indicate the location of a vessel and most do this task admirably.

Its a special case but knowing if you are navigating a tidal river (in the dark) it is also useful to know how 'large' (beam) is the vessel and anchor lights are not really designed to offer this information. An anchor light that illuminates the deck of the anchored vessel is so much more useful (as you then know you cannot sensibly anchor alongside if it turns out to be a beamy cat (like ours).

Just a thought

Jonathan

 

[Refueler]

Any of these: Lithium Battery Chargers | RS

In actual fact with JST plugs - you can have charger for less than a tenner - which auto shuts off etc. Runs of 12v

Yes they balance charge cells ..... so need for any BMS board ...

But they can only work with 4.2v max Li cells ... (normally stated as 3.7v nominal).