Keel stepped mast - water in bilges

[BlueSkyNick]

It is impossible to prevent water entering the top of the mast through halyard sheaves etc, and gravity dictates it can only come out at the bottom.

Hence water in bilges is inevitable..... or is it?

 

[Seajet]

As the mast has various holes for sheaves, electrics, exit sheaves etc, it seems it is indeed inevitable to get some rainwater straight to the bilges, hopefully not much.

This was certainly the case when I had a boat with a keel stepped mast, though in that case - Carter 30 - the mast foot was just above the shower tray, which seems a good idea.

 

[Lucky Duck]

My last two boats have had keel stepped masts, on the first (a Bene) you could watch the rain droplets cascade down the mast in the saloon when it rained heavily and the bilges needed the occasional mop up with a sponge.

With the current boat the bilges have remained dusty without a drop coming down the mast.

 

[sailorman]

As the mast has various holes for sheaves, electrics, exit sheaves etc, it seems it is indeed inevitable to get some rainwater straight to the bilges, hopefully not much.

This was certainly the case when I had a boat with a keel stepped mast, though in that case - Carter 30 - the mast foot was just above the shower tray, which seems a good idea.

a good auto pump diaphragm works well.
some fit a "Plug" just above deck level with drain holes onto the deck

 

[BlueSkyNick]

This was certainly the case when I had a boat with a keel stepped mast, though in that case - Carter 30 - the mast foot was just above the shower tray, which seems a good idea.

must have been a bit difficult having a shower with the mast in the way.

 

[Seajet]

Sailorman,

do you mean an auto bige pump ( as I indeed fitted ), or using a diaphragm as a seal in some way ?

The mast had the correct gaiter at the hole in the deck, but I can't see any way of preventing some rain getting inside the mast.

 

[Phoenix of Hamble]

Exit cables at deck level, and then plug the mast with closed cell expandable foam... One small drain hole, and problem gone!

 

[sailorman]

Sailorman,

do you mean an auto bige pump ( as I indeed fitted ), or using a diaphragm as a seal in some way ?

The mast had the correct gaiter at the hole in the deck, but I can't see any way of preventing some rain getting inside the mast.

diaphragm pumps are more reliable
the "Plug" goes in the mast to stop water ingress via the sheave box`s

 

[Seajet]

Sailorman,

I take it this plug at the sheaves is a temporary fit when at rest ? what about those for halliard exits up the mast, or is it something more intelligent ?

MoodyNick,

The loo/shower bulkhead went beyond the centreline so encompassing the mast within the shower area.

Phoenix,

I'm not sure I fancy what would effectively be trapping some small amount of water inside the mast against the alloy...

 

[sailorman]

Sailorman,

I take it this plug at the sheves is a temporary fit when at rest ? what about those for halliard exits up the mast, or is it something more intelligent ?

MoodyNick,

The loo/shower bulkhead went beyond the centreline so encompassing the mast within the shower area.

Phoenix,

I'm not sure I fancy what would effectively be trapping some small amount of water inside the mast against the alloy...

the plug is at deck level below the sheave box`s but above the deck

 

[Seajet]

So unless 100% effective, will either allow leaks below or trap water inside the mast; no thanks !

 

[sailorman]

So unless 100% effective, will either allow leaks below or trap water inside the mast; no thanks !

we have a pump

 

[Phoenix of Hamble]

Put the hole at the top of the bung and no more water will be trapped than you'd get in a deck stepped mast

 

[dt4134]

So unless 100% effective, will either allow leaks below or trap water inside the mast; no thanks !

I've the same arrangement as PoH describes. Works well. The previous owner had blocked the drain hole which didn't work well as water built up and came down the electrical conduits into the saloon. A new drain hole sorted that. Not had a drop of water into the saloon or bilges since.

 

[BlueSkyNick]

as advised by email from a friend ....

Water should technically not get down the inside of the keel steped mast as there is an obturator ( bung ! ) inside it just above deck level with a couple of small drainholes allowing water to drain onto the deck from just above the obturator. Selden sell some patent thixotropic ( runny ) mastic to retro inject to re-seal the obturator / mast join.

 

[johnphilip]

mast sealing

When we bought our boat there was still warranty on the Selden rig, quite bad leaks inside the mast were cured with a Selden kit, installed by Rig Magic and there has been no problem for over five years. Selden said to drill a 25 mm hole in the side of the mast to install the seal but Rig Magic managed with a much smaller 12-15 mm hole.

 

[Strathglass]

I have a keel stepped mast and a dry bilge.

It is a sparcraft section (F305) and had two alloy castings and a rubber moulded section at deck level.

There is also an internal dam at deck level with a drain hole to the deck.

The dam had a tube for the internal mast wiring which all exits the mast below deck level.

It is shown here.

http://www.sparcraft.com/uk/technic...erformance_range/fichiers/collerette_mat-.pdf

The collar assembly is the new style and the dam is shown at the bottom of the page. There are also three T tracks inside the extrusion for fitting plastic ducting for the wiring

The whole assembly was part of the mast kit supplied by Sailspar.

I did find that I has to add a sealant between the rubber collar and the mast to make it fully watertight.

 

[johnphilip]

So unless 100% effective, will either allow leaks below or trap water inside the mast; no thanks !

Any water running down inside the mast is released above the deck gaiter through a hole in the side of the mast just above the waterproof seal in the section.

Anyway what is so dredful about water in the mast, it gets plenty on the outside, and salt water at that

 

[Twister_Ken]

Exit cables at deck level, and then plug the mast with closed cell expandable foam... One small drain hole, and problem gone!

Of course, you then get leaks through the cable glands!

 

[Phoenix of Hamble]

Not if you seal 'em properly!