Threading a Wire in a Mast

[landonshaw]

I have a Aqua Signal tri-color light on the top of my mast and want to change to a tri-color & anchor light, series 40. To do this I need to thread an additional wire down the mast. How is this done?

Are the wires in a plastic pipe running the length of the mast to protect from the other ropes?

One more project.

[Ziggy]

Instead of pulling an additional wire, use the one feeding the tricolor to pull a triplex cable through the mast.

[mike d.]

what Ziggy said

[Blue Stocking]

It depends on the inner set-up of your mast. Most obvious way is to use the 2 wire to pull in a 3 wire if there is room.
There is away to run the 2 lights off of a single pair by using blocking diodes and a DPDT switch. The diagram is in the spiral bound handbook from Spa Creek. I will see if I can find my copy, but I will bet the knowledge is on this forum.

[barnakiel]

Thread the new wire with the old one.

b.

[rustypirate]

I agree to use the old wire to pull a new one, but while you are at it, pull a nylon or polyester string along with it so that the next time you need an additional wire run, you have something to pull it through with.

[nhschneider]

I suggest you consider installing 5-conductor mast wire. There may be a time in the future when you want to add a strobe light or some other piece of gear and it's very convenient to have a spare conductor or two. Using the existing 2-conductor as a pull string is a good idea as is pulling in an additional pull string but I've never had much trouble using an electrician's 'fish tape' to get more cable inside a mast.

Fair winds and calm seas.

[s/v Jedi]

Or, pull a messenger line with the old cable and after that the old cable plus the extra wire with the messenger line.

I have been successful with two different methods. One is a 50lbs fishing line with a small round lead weight on the end. Use some wire bend into a hook to fish for the fishing line at the cable-exit.
The second one was really good: use a vacuum cleaner and an audio-cassette. Pull the tape out of the cassette and feed it into the top of the mast while the helper puts the vacuum to the cable exit at the bottom.

cheers,
Nick.

[Talbot]

The OP asked why the wires are inside a conduit.

The answer is very simple, if they are not in the conduit, the banging backwards and forwards on the inner mast wall will quickly send you and any neighbour insane! This movement will also contribute to premature failure of the wire, and can also lead to chafe by internal halliards.

[clockwork orange]

Talbot, The OP didnt ask why but IF the wires are in a plastic conduit? No one can definativly answer that for him but i would guess it does on a boat like his,i agree that using the old wire to pull thru a 3 conductor plus messenger is the way to go as often the conduit is way too tight.
Steve.

[Joli]

You can also pull a cotton bit tied to mono filament line through the tube with a vacuum.

[Sandero]

Cables to the masthead in a aluminum mast are often run in a conduit or a separate "channel" extruded into the mast for that purpose. Considering the amount of electronics up there the conduit can become crowded: VHF, Wind Instruments, Navigation lights and strobe... and perhaps other antennas.

Conceptually pulling the new cable by taking it up to the top of the mast and disconnecting the one it is to replace from the lights and securely connect the new cable to the freed end of the old cable is a no brainer.

However it might be a bit crowded in the conduit or channel and you might consider applying lubricant to make the cable pull move freely. If you run into resistance when someone pulls from the mast base as you feed it down the top mast exist you may be trying to get too much into the conduit.

You could also pull from the top, but I suspect this is more difficult.

Remember some of the wiring exits midway up the mast for Radar for steaming, spreader lights and tv antenna etc. so the crowding may manifest at just below where these wires exit. Whatever you do, make the splice/connection between the old (pulled) and new cable being pulled as small, fair and strong as possible

[Talbot]

Originally Posted by clockwork orange

Talbot, The OP didnt ask why but IF the wires are in a plastic conduit?

The OP actually wrote "Are the wires in a plastic pipe running the length of the mast to protect from the other ropes?"

That is a question about why are the wires inside the conduit - which is what I answered.

[landonshaw]

So, what I can tell, their is a pipe of some sort that the electric lines run through in the mast to keep them from making noise and chafing. I am replacing the mast light with a light that has a strobe, anchor, and tricolor so will need 4 wires.

Comment was made to run a fifth? I am also in the future going to put a wind and directional vane on top of the mast. Does this take a special cable? If this is the case, would it be better to run a wire with 4 strands and also a fishing line to pull the wind vane cable up at a future date?

All of the comments are again very useful thank you.
Dave

[Talbot]

Originally Posted by landonshaw

So, what I can tell, their is a pipe of some sort that the electric lines run through in the mast to keep them from making noise and chafing. I am replacing the mast light with a light that has a strobe, anchor, and tricolor so will need 4 wires.
Comment was made to run a fifth? I am also in the future going to put a wind and directional vane on top of the mast. Does this take a special cable? If this is the case, would it be better to run a wire with 4 strands and also a fishing line to pull the wind vane cable up at a future date?

Wind instrument will be a special cable, so make sure you leave a fishing line.
assuming you are going led rather than incandescent bulb, a thinner cable with 5 strands is a good idea - thus having a spare. If 25w incandescent bulb, then you need to keep the guage of the wire large enough not to lose to much power (it is uphill so will struggle)
In the future you may be replacing the VHF aerial - while doing all this, definitely worth looking at the condition of the aerial wire. Make sure you replace this with tinned aerial coax optimised for vhf.

You may in the future also need to look at the steaming light (and the deck illumination light if fitted)