Getting wiring down the inside of mast?

[Tomkat17]

What is the best technique to feed a cable down the inside of a keel stepped mast (upright). I have an exit hole already in the mast inside the saloon made by the previous owner.

 

[lenseman]

Firstly you will need two, possibly three people. One up the mast, one in the saloon and a third to keep an eye on the person up the mast and to act as a goffa between both stations. Women are very good at this job.

The person aloft requires a large heavy sail-makers needle or elastic bobbin and this is attached to some heavy-duty thread (long enough to be dropped the full length of the mast from the masthead hole plus a little bit more and thence into and through the 'hole' in the cabin.

Initially, it would be a very good idea to lower the threaded 'bobbin' external to the mast to accurately measure the amount of thread required to arrive at the 'exit hole'. Allow a further foot and then mark this position by tying a knot in the thread.

The receiving person below in the cabin will require a 'hook' made of thin bendy wire and strong magnet (rare-earth type) to attract the bobbin to the exit hole. Bendy wire can be formed from the 'flat twin and earth' wiring used in any house. Strip out and use any of the three wires without any of their insulation. The earth wire is good.

The mast head person will have to have a very gentle hand when lowering and paying out the thread, feeling the whole time whether the thread has snagged inside the mast. Best to assign this job to a fisherman who is used to playing a 6lb perch on a rod and line with a 2lb breaking strain!

The thread can then be used as a pull-through for heavier duty ball of string and finally the RG58 cable for the antenna.

Use no knots to join the string to the co-ax but use insulating tape binding the string along the length of the co-ax for at least a foot.

The final thing you will require is a load of patience.

 

[Malish]

check to see if there is a conduit inside the mast - if yes then try to feed the cable down it - it is there to stop cable chafe by the halyards and also avoid cable slap against the inside of the mast (which rapidly becomes very annoying - trust me!). To feed the cable down the conduit you may have to use either a length of old rigging wire or a 'fish' which is purpose designed for the job.
If you are just going to drop the cable down the inside of the mast (no conduit) then a length of bike chain works as a suitable weight which can be drawn through the aperture at the bottom. I would urge you to place 3 x tie wraps every couple of metres with their tails at 120 degrees to each other to prevent the cable slap.

 

[rjg101157]

I did this only last weekend using an old bike chain and worked perfectly. Good luck!

 

[saltwater_gypsy]

Drop by the fishing shop and get a box of small spherical clip -on lead weights and a reel of light monofilanet line. Clip the weights on to the end of the line and off you go!!

 

[Cariadco]

Brilliant!! Ace Ideas - Chain, Cable Ties......and something to keep the Missus busy!!
(hopefully she won't read this)

 

[Eeyore]

[ QUOTE ]
check to see if there is a conduit inside the mast

[/ QUOTE ]

Stupid question I know, but how would you check if there was a conduit in the mast whilst it is up?

 

[oceanpilgrim]

Hi
did mine with lowering fishing line down the mast with a small nut tied to the end,not stainless,place an old speaker magnet next to the mast next to the hole,you can feel it click to the in side of the mast slide over the hole job dun,you can also buy pick-up magnets small swivel headed magnets on handles from car part suppliers,ie halfords ect

 

[rhumlady]

If you have conduit on the mast you will see a pair of pop rivets every metre or so on the outside of the mast. I find a roll of springy curtain wire good for running cables and halyards etc in the mast and boom. It is strong enough and flexible and if you have an eye on the end it pushes through easily.

 

[roger]

When you get the messenger (light line) through, pull through enough cordage to have a full length of the cordage spare and connect the cable to the centre of the cord. You then have a second chance if the cable separates from the cord.
When you have succeeded leave a length of cordage strung through the mast to make it easier when you install the next wizard gadget.

 

[Tomkat17]

Thanks guys for all the great suggestions.