Mast wiring

[drh1965]

Does anyone have a recommendation for a fitting to pass mast wiring through the deck? My mast lights need to be rewired and I want to have better access to the wiring.

Thanks.

[Pura Vida]

One fix that I like, but had never tried myself, uses two deck fittings like you would use to support a bimini and a hose between them. The idea is to place one over the hole in the mast, sealing it of course, and then the other goes on the deck. Wiring from the mast exits the fittings, goes through the hose and then into the deck. The hose is held in place on the fittings by hose clamps. To do this properly the hole for the wiring needs to be high enough above the weep hole in the mast so that it does not become a drane into the cabin. The big con is there is now a loop on the deck to catch a foot in, etc.

How's the sailing been?

pv

[GordMay]

Search " Deck Connectors " & " Cable Clams ".

[drh1965]

Originally Posted by Pura Vida

One fix that I like, but had never tried myself, uses two deck fittings like you would use to support a bimini and a hose between them. The idea is to place one over the hole in the mast, sealing it of course, and then the other goes on the deck. Wiring from the mast exits the fittings, goes through the hose and then into the deck. The hose is held in place on the fittings by hose clamps. To do this properly the hole for the wiring needs to be high enough above the weep hole in the mast so that it does not become a drane into the cabin. The big con is there is now a loop on the deck to catch a foot in, etc.

How's the sailing been?

pv

I'm still fixing things. I just got my replacement water temp gauge. Once I install that, the boat will be ready for day time sailing. We're planning to make our first "real" sail Christmas week. I'm a little nervous but it should be a blast!

[drh1965]

Originally Posted by GordMay

Search " Deck Connectors " & " Cable Clams ".

Thanks Gord. I found a post you made about the Blue Sea Cable Clam. I've never seen one. I assume that little rubber gland squishes around the wiring as the connector the top plate is tightened. If a wire bundle goes through, would it still seal? Would it be possible to run a PVC pipe through the clam and pass the wires through it? Or would the PVC crush?

[Lancerbye]

If you have a bottom mast access plate and a through hole inside the mast into the mast step, run the cables through and then use ducseal a putty used by electricians to seal a varirty of things. It is pliable and can be formed to go around all the wires individually and peaked to provide a water shedding seal. Don't use sealant like 5200 or sikaflex as I have seen used. You might want to make some changes without destroying all your wires.

[GordMay]

The Cable Clam (glands) are made for a jacketed cable, but if you put a heat shrink around the wire bundle (where it transits the clam) it will seal pretty well. The more consistently “tubular” you can make the bundle, the better it will work.

There’s also Deck Connectors (2 Pin & 4-Pin, by Perko & SeaChoice)) that work fairly well, though they tend to corrode over time (but, what doesn't?).

[David M]

Originally Posted by drh1965

Thanks Gord. I found a post you made about the Blue Sea Cable Clam. I've never seen one. I assume that little rubber gland squishes around the wiring as the connector the top plate is tightened. If a wire bundle goes through, would it still seal? Would it be possible to run a PVC pipe through the clam and pass the wires through it? Or would the PVC crush?

I have used these, you have to drill one hole for each wire jacket. Running the wires through it bundled together will not work. I take self-annealing electricians putty (this is not electricians tape although it does come in rolls, it never hardens and is not messy) and put it in there and let it squish out as I am tightening down the screws for extra watertightness. This works for jacketed multistrand wire that is not round. Experiment with drilling the holes by starting out with a small bit first...the holes do not come out the same size as the drill bit when drilling through the rubber. I know this is counterintuitive but that's what happens.

You could use pvc (abs preferably) and run the wire bundle through the middle of the pipe...you would still have to seal the end with something like the electricians putty. This is probably not as good as the first method...and would not be as clean looking an installation.

[GordMay]

Originally Posted by David M

... I take self-annealing electricians putty (this is not electricians tape although it does come in rolls, it never hardens and is not messy) and put it in there and let it squish out as I am tightening down the screws for extra watertightness. This works for jacketed multistrand wire that is not round ...

3M “Scotchfil” putty (electrician’s putty) is a great weather-proof build-up compound & insulator for irregular surfaces.
Rather than merely apply it to the bundle, then let it extrude out the clamp; I would use it to “round out” the bundle, under the shrink wrap sleeve. This makes for a durable (re-usable) and clean assembly.