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Two piece masts problem solving

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dave42w
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Two piece masts problem solving

Post by dave42w »

Hi,

I have read the "Leaky Masts by Bob Carter (April 2004)" article on the tips page. Not sure how my issue relates.

The bottom section has some water in it. So we separated the sections to put the lower mast upside down to drain.

a) the joining section was loose and came out. It has some water inside it. When I stand it upside down the water leaks out very slowly.

b) the upper section has now been upside down for 36 hours but no water seems to be coming out.

I've cleaned the inner joining section with cycling citrus cleaner and it has come up nice and clean.

Questions

1. should the inner joining be fixed into the lower mast section? If so then how?

2. How long do I wait for the water to drain before giving up and using the drill a drain hole route?

Thanks

Dave
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Bob Carter
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Re: Two piece masts problem solving

Post by Bob Carter »

Dave,
Your boat was built in South Africa and there are a number of differences with the UK built masts. The mast split is higher up the mast and the jointing piece is meant to be fixed in the top section, but I'm not sure how. It is not a big deal if it is not fixed as long as it not so loose that it could fall out in transportation when you have the mast separated. The jointing piece became fibre glass when the mast went to South Africa. It is hollow and should not leak. It needs to be emptied, dried and sealed. I have never owned a South African 2 piece mast (mine was 1 piece) but I suspect it would not hurt to drill a couple of small holes one at each end to facilitate draining it. You then need to find and mark the source of the leak. Once this is done you could dry the joining piece in the airing cupboard. When dry the joining piece needs to be sealed - both the new holes and the leak site. This can be done with epoxy resin. It might be worth consulting Brian Phipps of Windsport on my suggested procedure before undertaking it.
It sounds like the top section of your mast does not contain water and is OK but the bottom section leaks and contains water. This is the classic leak and is caused by the sealing plug at the top of the bottom section having a slight leak and the rain seeps into the lower mast over time when the mast is upright. Your boat is 10 years old so it has had 10 years for water to creep in. It is normal for the lower section of the mast to take a long time to drain when inverted. Several days is normal - I found they drain best when angled from the vertical.
I have never managed to replace the sealing plug and effect a permanent seal. Once it is drained you have a few options.
1) you can live with it for a period and see how quickly water builds up. It may not happen at a very significant rate and an occasional drain might be adequate. This can be accomplished by putting the mast top down when trailing.
2) you can use the plug and screw technique I talk about in the article.
3) another option is to seal the fibre glass joining piece in the bottom section of the mast using lots of silicone sealant. This will make the lower section of the mast longer than the top section but that does not matter much. It also means that it will be very difficult to remove the joining piece from the mast for any reason.
I suggest that you start by trying option 1 above as it has least downsides.
Regards
Bob
PS Most UK built boats from sail number1200 have an Aluminium extrusion joining piece and it was this I was referring to in my article. The early Sparks had one piece masts but then Panthercraft sold a kit which enabled the owner to cut his own mast in 2 and make it into a 2 piece mast. The kit included a fibreglass joining section like yours. I have the kit instructions for this kit that I will send you if you send me your email address. You can do this by the private messaging facility on this chat page or alternatively send me an email to technical@sprint15.com
dave42w
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Re: Two piece masts problem solving

Post by dave42w »

Bob Carter wrote:Dave,
Your boat was built in South Africa and there are a number of differences with the UK built masts.....
Thanks Bob, that is really helpful!

Lots to try and no real rush which is good.

Dave
Charles
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Re: Two piece masts problem solving

Post by Charles »

Resurrecting this rather old thread as I have water in my bottom mast section.

Not a problem, I thought, just drill a hole slightly above the mast foot & hey presto.

Not so easy, apparently. No water came out but it is still sloshing about inside.

Is there a plug towards the bottom of the lower section & roughly where? I don't want to be drilling holes every foot until I find the water!
Charles
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edchris177
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Re: Two piece masts problem solving

Post by edchris177 »

Yes, there is a plug in the bottom section.
My bottom section got filled with water last year, after I turtled the boat, stuck the mast in the mud & couldn't get it out til a powerboat came & gave me a tow.
I needed to replace the small plate inside the mast base anyway, the one that is contact with the mast ball, so I removed the base. There is a plug, about 4" up from the bottom of the extrusion.
The plug is sealed with some sort of brown goop, & a small void was missed, which allowed the bottom section to fill when the boat was turtle.
Initially I was going to just seal it up, but if water gets in from the top, it would be difficult to get out. I drained the mast by leaving it on an angle, bottom down, for few days. I then used a hot wire to melt a small channel through the plug, this will allow any water to easily drain into the hollow between the plug & the mast base. The mast base, (with new wear plate), was reinstalled, (being sure to seal it so water could not get in during a future turtle).
I also drilled & tapped a 1/8" hole just above the mast base, (it only extends into the extrusion 1"). I keep a screw with thin rubber washer in this hole. I remove the screw at the end of the season. Any water that gets in from the top will flow to the bottom, & easily drain by removing the screw.
I forgot to measure how long the plug at the bottom was, I'll see if a "stud finder" can discern between the hollow part of the mast, & where the plug is.
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edchris177
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Re: Two piece masts problem solving

Post by edchris177 »

I forgot to mention, in your case Dave, drilling between the plug & base will not solve your problem if the leak is from the top of that section, AND the plug at the bottom is fully sealed. The water can't get past the bottom plug!
You could invert the bottom section & see if the water will drain out. From reading Bob Carters writeups, it seems sealing from the top is a mugs game, water is going to get in.
For that reason I decided to make it easy for the water to drain to the very bottom, then let it out via the small screw.
I had contemplated drilling a 1/16" hole in the mast base, allowing the bottom section to continuously drain, but bugs might clog the hole, & it would allow ingress during a turtle. It is easy to right these boats from turtle, but some parts of the 750sq km lake I sail on are only 16'-20' deep, & I may well put the stick in the mud again.
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