wiring for masthead instruments/lighting

I would have thought that this would be an easy thing to find information on, but after a couple of days of searching I can find essentially nothing of practical use.

I am installing a windex light and wind instruments on the top of my mast. I am concerned about keeping weight down to a minimum, and aren't crazy about drilling all kinds of holes or any hokey cable arrangements at the top of the mast. Can someone advise on:

1) How should the cables be retained at the top of the mast (so that the weight of the cable is not hanging off the connector)?

2) How should the cables be led through the mast top? I would prefer to do this through the flat plate on top of the mast, as opposed to the mast wall. What kind of connector should I install at the mast top?

 

1) How should the cables be retained at the top of the mast (so that the weight of the cable is not hanging off the connector)?

errrmm ....A Knot?

2) How should the cables be led through the mast top? I would prefer to do this through the flat plate on top of the mast, as opposed to the mast wall. What kind of connector should I install at the mast top?

Plastic cable gland, example here: http://www.ghlucas.co.uk/products/plastic_cable_glands.htm

You will of course have to sika the threaded section in unless you can reach to put the back nut on! Or you could give up on making it watertight and just make sure it won't chafe with some thick hose

The big question is how to stop the damn cable banging around inside the mast... There are few answers to that one - most involve holes in the mast wall. the best one I've heard of is shuttlecocks on a string pulled up the inside of the mast - unfortunately it does involve acess to the open bottom of the mast!
One tip if your mast is still up and you are going up in a bosuns chair, take a 2m length of rope or webbing with foot size loops in each end. When you get up there run it over the top of the mast and you can stand up in the loops to see what you are doing - higher than the level that your chair will take you too. - Stay strapped in though!

 

another simply method to stop that incessant rattling is to use nylon "tie-wraps", which you can usually buy at most electronic supply houses... maybe even a hardware store. buy the size that is at least the diameter of the mast.

apply three tie-wraps at each 'station' arranged at 120 degrees, and leave all the excess "end" on. place them on the electrical cable at intervals of about three feet.

when you feed the cable into the mast, the 'excess ends' will extend away from the electical cable and act like springs, centering (more or less) the cable in the mast.

a clever idea, regrettfully not my own.

 

dammn that IS a clever idea. Thanks!

(wish I'd thought of that!)

Paul

 

A good way to prevent the wiring from hanging off the connector, is to use a stainless steel webbing with a hook built on it. It is specially made for wiring. As the wire pulls, the mesh tightens. The main advantage is that it spreads the load over a long section of the wire.

 

CLARIFICATION:

When I said, "buy the size that is at least the diameter of the mast." I was referring to the length of the ty-wrap being at least as LONG as the diameter of the mast.

Sorry if there was any confusion about this.

Lew