Sealing concrete, cabin sole

[Mercrewser]

I decided to attack the cabin of my boat before sailing it.  I tore out all the plywood, and shoveled about a 100#s of concrete out after ripping up the fiberglass sole.  I have not read anywhere on this site what to do after pouring in new concrete.  I'm sure the ballast has already been compromised, there are some blisters on the keel.  The boat is currently undergoing a drying process before reconstruction.  What do you guys reccomend for sealing the cabin sole after the concrete has been poured?  Should I lay down some mat and spread epoxy on it?  How long should I wait after pouring the concrete?  I dont want water getting down there in the future, after all of my hard work.

[Whitecaps]

Mercrewser,

The cabin sole in Arunk (my CP-16) was not in that bad a shape.  We pulled up part of the delaminated fiberglass, but not all as it was in pretty good shape.  The concrete was still in good condition so we basically resealed with epoxy and fiberglass cloth and several more coats of epoxy to smooth it out.  Before doing all that we drilled several holes up through the bottom of the keel to allow any water remaining to drain out.  

As far as new concrete goes, I would think that if you allowed it to cure for a couple weeks before sealing the cabin sole with epoxy you should be okay.  Of course most of the water in the concrete will be taken up in the process of curing within hours.  But some moisture may remain for days.  It wouldn't hurt to drill a couple holes up through the bottom of the keel as we did to allow any excess to drain out.  Of course this creates extra holes to seal before launching, but if you're dealing with enough epoxy to seal the top of the keel what's another few small holes?

Grant White
Arunk

[mhallas]

i just did this too recently, i scraped out about 3 gallons (volume-wise) of loose rubble, then coated with epoxy and then glass.  Im thinking about placing some rubber roofing in there, with the edges curled up. Sounds like overkill, but i just finished fixing a 3x7 hole in the keel from expanded water. That is a whole other story that ill tell sometime....what a disaster...

matt hallas
cp16 #255 "Sarlacc Pit"

[PaulE]

I've sealed mine using the kit they sell at the big orange store for putting an epoxy coating on your garage floor.
I just left out the sprinkles and added a whole tube of white pigment to lighten the grey.
The epoxy kit was about $60

THis made a nice smooth, easy to clean floor.

[Whitecaps]

Hi PaulE,  That sounds like the way to go.  I considered that, but didn't know how much would be leftover and whether the leftover would be usable later.  How was it to work with?  Does it cure hard, or is there a soft feel to it?

[PaulE]

It cured pretty hard but, not too hard. Sorry if that doesn't make too much sense.
I did have quite a bit left over. But, I there would be before getting started. For the price, though, I figured it was still a good deal.

The hardest part was ensuring the top of the keel was level.
I put the trailer up on block to remove any suspension movement, then placed a level on the keel. Then I just kept putting wood shims between trailer and blocks until it was level in all directions.
I created the epoxy mix with all of the supplied (to keep the mixture correct, very important with epoxy). Separated half.  Then I added a full tube of white pigment (from West) into it to lighten the grey.
Last step was to pour it in until there was no visible concrete.

If you want to use the leftover, you'll need to use it right away. Plan ahead.
I really don't recommend splitting the premixed stuff due to epoxy's sensitivity about correct mixture. Also, don't lay it on too thick or you'll get too much heat buildup which could result in bad things.

[sawyer]

When it comes to concrete the curing time and strength is based on water to cement (that is the powder) ratio. The less water, the stronger it is and has less chance of turning to rubble.  Curing time for concrete at 60 degrees is 7 days for 75% strength, and 28 for 95% strength, After the 28 days time it is negligable.  It will create it's own heat for about a week. Interestingly, ideal curing conditions of concrete is under water to prevent fast bleed off of moisture, but for a keel filler, anything should be ok.  I think that I would leave it open and curing for 28 days before sealing with epoxy. Just my thoughts, I have poured a lot of concrete over the years.

Doug/Merry
CP-16 II
"SISKIWIT"

[K3v1n]

Yep this is another project that needs attention on my CP as well. I purchased the fast curing mix, well see how that works. Then I plan to glass it over to keep the keel water tight. I'm thinking then I'll make a nice wooden sole to cover it all up.

[B.Hart]

This was a project of mine last summer. I spread a layer of portland to smooth out the concrete, then reglassed the keel.

[DanN]

Well, it looks like my 1996 Compac has the usual problem of the cabin sole delaminating and allowing water into the ballast.    It doesn't seem that bad yet as far as destroying the concrete, but I'm definitely getting water down into the keel and I think I got some damage from freezing last winter.     What's the least invasive way of fixing this?   Do I have to remove  the bunk supports in order to get at the sole?   If so, do they disassemble nicely or is it a matter for saw and prybars?

  Can I just squeeze a whole bunch of epoxy underneath the existing fiberglass and hope for the best?

   Has anyone ever tried constructing a small bilge in the cabin to make it easier to remove water?   I have already caulked the joint seam under the rub rails, but it looks like there might be other sources of leakage.  I'm toying with the idea of chiseling a small basin in the concrete and then fiberglassing over it so I can get the end of a small hand pump in there.

[Gil Weiss]

I think you mentioned the solution - seal the leaks. My 1990 CP 16 looked in pristine shape when I bought it 4 yrs ago but had rub rail (hull/deck seam) leaks, the scuppers leaked and the round ports on the seats back at the transom leaked. In my case the scupper leaks were the worst culprit as they let lots of water into the bilge area back at the transom. The water would then run down the bunk onto the cabin floor.

Once I sealed all the leaks the issue of water on the cabin floor went away.

[Liane]

Hi Guys

I'm dealing with a similar problem:  the fiberglass liner (the cabin sole?) cracked out at the bulkhead, water got in and sat.  Am currently replacing the bulkhead.  Water definately got down in the keel.

When I pulled up the sole, there was concrete in the keel but not "around" the keel between the berth supports -- is there supposed to be?

I also read about drilling holes in the bottom of the keel to drain water.  What exactly is the "epoxy" you are using to fill those holes?  Is it the same epoxy used when applying fiberglass (i.e. the hardening resin type goo)?  If so, do you just paste the epoxy (with no fiberglass) on the holes?

OK, obviously I'm new at this.  Trying to gather info. 

THanks! 

Liane

p.s. what exactly is a "transom"? 

[DanN]

I also read about drilling holes in the bottom of the keel to drain water.  What exactly is the "epoxy" you are using to fill those holes?  Is it the same epoxy used when applying fiberglass (i.e. the hardening resin type goo)?  If so, do you just paste the epoxy (with no fiberglass) on the holes?

I usually mix some filler into the epoxy to make a paste out of it.  West System (and most other epoxy dealers) sell various kinds of powder filler.   This has two advantages -- it's stronger and, because it's a paste, it doesn't drip.   I imagine you could also use the various kinds of marine repair epoxy (the kind you knead and use)  which would be cheaper than buying a full container of West System.  I imagine even Bondo would work in a pinch.

[sawyer]

To: Liane........

Transom......   Back of the boat, stern, fantail, where the motor on a little fishing boat mounts, where the name of the boat can go, where to mount the swim ladder, the part where the rudder hangs on its mounts........            CP-16 has one,  I think the Eclipse does not...........            Doug

[Liane]

Thanks guys.  Slowly but surely, I'll get it down. 

Tipped the trailer and drilled a 1/8" hole in lowest point of keel, but never got any "dead space" where water could accumulate, only "keel-stuff" (not quite concrete, I don't think, more like plaster or something).
IS THE KEEL FILLED FULL UNTIL CLOSER TO THE TOP?

I got a crack from accumulated water over the winter (bad cabin sole, as above) in the keel about 8" down from top.

Am planning to patch with West Systems epoxy and a little glass, this weekend.

Just sanded down to beige fiberglass weave, was going to glass over it, as suggested in other posting ("crack in keel" I posted).