NMEA Cable through Deck Problem

[KelseyB]

Hey all, here's my problem:

We just ran wind instruments. All of the other masthead wires for lights, VHF, etc go through a gooseneck at the base of the mast, but it is full and there is not room for the NMEA plug at the end of the wind instruments wire to fit through it without unwiring and rewiring all of the other things, which I'd rather not do.

We plan to run the wind instruments wire through a preexisting hole through the deck next to the gooseneck (there were three ancient pre-NMEA plugs at the base of the mast that weren't doing anything but plugging holes, so we removed one of the plugs, and now there's a hole that it can fit through). The trouble is with sealing it.

Every other place on the boat that a lone wire runs through the deck, we have one of those cable-sealer things that you drill through, run the wire through it and the deck, and then it seals itself around the wire. But this won't work because the NMEA plug has to fit through, and it's significantly larger than the wire itself, so if we drill a hole through the cable-sealer large enough for the plug then it won't seal around the wire. As a temporary solution, we're going to run the wire and seal it with some silicone, and then we can just remove the silicone when we come up with a permanent solution. Does anyone have any ideas on how to permanently seal this wire in place? Important note: the hull is steel.

[Nekton73]

Google "split cable gland" and you will find things that may solve your problem.

[Lake-Effect]

I've used the typical blank gland:

... I drill a hole in the black puck that's sized to hold the wire tightly, and then I use a very sharp hobby knife to cut from the side of the puck into the hole. (you can put a few such slotted holes into a puck, depending on sizes)

You mount the gland enclosure, feed through the wire(s), and push the wire sideways through the cut in the puck, into the drilled hole. I like to add a touch of some sealant as i do this: silicone, butyl, etc. Put the puck with wires into the enclosure, slide the ring on and tighten it down. Sealant should ooze out. Done.

[Bellinghamster]

split gland, or cut the wire, feed through the seal and put male and female field-installable connector (or terminal block) below deck.

[KelseyB]

Originally Posted by Lake-Effect

I've used the typical blank gland:

... I drill a hole in the black puck that's sized to hold the wire tightly, and then I use a very sharp hobby knife to cut from the side of the puck into the hole. (you can put a few such slotted holes into a puck, depending on sizes)

You mount the gland enclosure, feed through the wire(s), and push the wire sideways through the cut in the puck, into the drilled hole. I like to add a touch of some sealant as i do this: silicone, butyl, etc. Put the puck with wires into the enclosure, slide the ring on and tighten it down. Sealant should ooze out. Done.

I have these elsewhere on the boat and they're great, my concern though is the vast difference in size between the NMEA connector on the end of the cable and the cable itself. I'm worried that to get the NMEA connector through, I will have to open up the gland too much and then it won't seal around the cable unless I lather it with another sealant, although I guess I could just do that.

[KelseyB]

Originally Posted by Bellinghamster

split gland, or cut the wire, feed through the seal and put male and female field-installable connector (or terminal block) below deck.

Can't do that, unfortunately. The whole reason we had to run a new cable in the first place is because someone cut the connector off the original cable to run it, and then the connector couldn't be spliced back on. Maybe someone very talented at splicing together data cables could do it, but I'm not inclined to take that risk.

[Statistical]

Originally Posted by KelseyB

Can't do that, unfortunately. The whole reason we had to run a new cable in the first place is because someone cut the connector off the original cable to run it, and then the connector couldn't be spliced back on. Maybe someone very talented at splicing together data cables could do it, but I'm not inclined to take that risk.

Field installable connectors have screw terminals. No splicing required.


The other option is a split gland. The hole is only big enough for the wire but it has a split so you can slide the rubber part onto the cable without removing the connector. Yes sealant on top of that can be used for belt & suspender aproach.

[Statistical]

Originally Posted by KelseyB

I have these elsewhere on the boat and they're great, my concern though is the vast difference in size between the NMEA connector on the end of the cable and the cable itself. I'm worried that to get the NMEA connector through, I will have to open up the gland too much and then it won't seal around the cable unless I lather it with another sealant, although I guess I could just do that.

You don't make a hole the size of the connector. You remove the rubber part and make a hole the size of the cable and then cut a slit from the hole in the center to the edge. Now you can put the rubber part around the cable without removing the connector and install it in the housing.

They are also available from some brands pre-cut. Not the same part but it illustrates how the slit works.

[deblen]

ThruDex cable glands have a cut in the rubber,from the outer edge of rubber to the predrilled cable hole. You put the plug/connecter thru the plastic outer part,open the slit rubber,insert cable in slit to center hole & screw the whole thing to deck The work great.
https://boater-supplies.com/product/...ru-fittings-2/


These Seaview are also split similar to Thru Dex. https://defender.com/en_us/seaview-cable-seal

[KelseyB]

Originally Posted by Statistical

You don't make a hole the size of the connector. You remove the rubber part and make a hole the size of the cable and then cut a slit from the hole in the center to the edge. Now you can put the rubber part around the cable without removing the connector and install it in the housing.

They are also available from some brands pre-cut. Not the same part but it illustrates how the slit works.

Aha, I see! that would work

[Lake-Effect]

Originally Posted by KelseyB

I have these elsewhere on the boat and they're great, my concern though is the vast difference in size between the NMEA connector on the end of the cable and the cable itself.

Perhaps you misunderstood (or my description sucked). The point is: you don't pass the connector through the drilled hole in the puck.

You drill a small hole in the puck that will be tight to the wire, then you slice into the puck side, to the drilled hole, and now you can just push the side of the wire through the cut and into the hole.

The connector just has to pass through the gland "frame", before the wire is snapped sideways through the cut and into the drilled hole in the puck.


[edit - thanks statistical and deblen for the better explanation and images]

[s/v Jedi]

With one of the field installable plugs you can now fix the other instrument and sell the new one

[KelseyB]

Originally Posted by Lake-Effect

Perhaps you misunderstood (or my description sucked). The point is: you don't pass the connector through the drilled hole in the puck.

You drill a small hole in the puck that will be tight to the wire, then you slice into the puck side, to the drilled hole, and now you can just push the side of the wire through the cut and into the hole.

The connector just has to pass through the gland "frame", before the wire is snapped sideways through the cut and into the drilled hole in the puck.


[edit - thanks statistical and deblen for the better explanation and images]

Yea I definitely didn't get it at first but I 100% see what you mean now, that's definitely the solution!