Multiple Wires Through Deck Gland

Spirit (of Glenans)

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I intend to replace the swan neck, through which my mast wiring ( tricolour nav & steaming lights, VHF antenna, Clipper wind), goes through the deck, with a deck gland like this one, which I have already bought:
https://www.indexmarine.com/wp-content/uploads/2017/05/DG30-family-Data-Sheet.pdf
However, I recently saw on this forum a photo of a mast base where the wires were led to four individual glands. What is the general opinion as to how many wires can be put through a gland like this, which purports to be able to accomodate multiple wires?
 
I’ve found that with carefull cutting the rubber gland can fit up to four cables as long as it’s sized correctly, any more it does nor seem to compress evenly and leak, it also helps if they are of similar size cables and spaced evenly

the problem can be that the more cables that go though the less room for any connectors on the ends to pass through the deck hole, this may be why some use more glands.
 
I’ve found that with carefull cutting the rubber gland can fit up to four cables as long as it’s sized correctly, any more it does nor seem to compress evenly and leak, it also helps if they are of similar size cables and spaced evenly

the problem can be that the more cables that go though the less room for any connectors on the ends to pass through the deck hole, this may be why some use more glands.
I've only got four cables, all fairly slim, and the only one with a permanent connector on the end is the VHF, so on that account I should be OK. Presumably placing the holes in a square formation would be recommended, although I would give some consideration to putting the largest one in the middle and having the other holes in a triangular formation around it . I can't tell from memory whether they differ in diameter, but they probably do.
My other thought would be to coat the cables in Sikaflex ,or something, similar before inserting them in the gland.
 
I chose to keep the swan neck, it lets plugs and sockets through.
I added a heat shrink wrap extension to reduce green water ingress.
 
Why do you want to go from a swan neck to a cable gland?
I've only come across people who's deck core has been wrecked due to a leaking gland and after repairs have changed to a single swan neck
 
Well, this particular gland is designed to do exactly what you want, so follow the instructions about hole size and placement and it should be fine.

Boats using several single glands where a multi one would suit is probably more down to what was available on the chandlery shelf or what possibilities the owner was or wasn’t aware of.

Pete
 
It's not the ability of the well installed swan neck that is the cause of my problem, but what happens when I tack and the new working sheet becomes snagged on it.
Up to this, I have lived with the situation and have been able to get to the mast in time to disentangle it before the sheet becomes loaded, but recently adjusting the removable backstay etc., in order to work on the furling system has (temporarily) caused stresses in the coachroof which precipitated a leak at the swan neck. I'm now taking the opportunity to replace it.
 
I believe they come in multiple sizes - so as someone mentioned above take guidance from them - I have a small one with two irregular sized cables through it and have had no issues - I read somewhere that a smear of grease in the sliced grommet thing, before you compress it, also helps..
The one that I have is, AFAIR ( it's on the boat), 30mm, like the one I linked to in the OP. When I bought it it seemed to be an adequate size to acommodate my cables, with a good amount of surface area remaining. The smear of grease seems like a good idea, it will not set like a sealant, so no ill effect if disturbed.
 
It's not the ability of the well installed swan neck that is the cause of my problem, but what happens when I tack and the new working sheet becomes snagged on it.
Up to this, I have lived with the situation and have been able to get to the mast in time to disentangle it before the sheet becomes loaded, but recently adjusting the removable backstay etc., in order to work on the furling system has (temporarily) caused stresses in the coachroof which precipitated a leak at the swan neck. I'm now taking the opportunity to replace it.
You can extend a web from the swan neck down to the deck to stop lines catching. It might not help in your situation, however. When done like this is can make a useful attachment point for harness lines as long as the swan neck is bolted through the deck?
 
My other thought would be to coat the cables in Sikaflex ,or something, similar before inserting them in the gland.
No, don't do that! The critical bit is checking the instructions to make sure the holes are the correct size for the bung to compress round the cables. Also if you can arrange a drip loop so cables don't go straight down into gland, that will help.
 
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