false keel

[kenowens]

Hi. When I was installing a rudder shoe on my Pearson Triton hull 554, I discovered a false keel filled with foam. Should I open the keel or the false bottom inside the boat to access this area to layup glass? Thanks, Ken.

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[CapnK]

Hi Ken -

I've seen owners of Tritons, Ariels, and A-30's all talk about the same thing.

Personally I would like to get rid of foam down there, because it's been my experience that even closed cell foams will absorb water, given immersion and enough time. I'd fill the area with a stiff paste of resin, microballoons, and milled glass. That should fill the area and give at least as much, if not more, structural strength than the foam has been doing.

[kenowens]

Thanks. The foam in the false keel is open cell and soaked with water as you said. Have you heard of anyone opening the false bottom of the bulge and removing all the foam? This would allow me to layup glass inside the false keel to compensate for grooving the hull for the shoe. I could also open the side of the keel but I prefer the later. Thanks again for your comments. Ken.

[kenowens]

Hi. When I was installing a rudder shoe on my Pearson Triton hull 554, I discovered a false keel filled with foam. Should I open the keel or the false bottom inside the boat to access this area to layup glass? Thanks, Ken.

PXL_20210609_192304410.jpg

[CapnK]

Both ways would do it, but from the top is probably easier in the long run. One thing to be cautious of is that when filling in a large space like that, or any time when you have a large amount of resin in one lump, the amount of heat generated during the reaction between resin and catalyst can be quite considerable. There are ways to control that, however.

One easy way would be to do multiple, smaller pours into the cavity, over a period of days. Great, if you aren't in a hurry.

You could cool down the resin ahead of time to create a slower & cooler reaction, but I am not sure if there are guidelines to follow on that.

While I generally like to use epoxy resin in refitting/repairing because of its much higher secondary (mechanical) bonding characteristics, I think for doing this job I would use polyester or vinylester resin. The bond isn't so important and should be sufficient. More importantly, though, you can limit the catalyst used in order to make a very slow, but nice and cool, hardening reaction and cure. Bonus: it's cheaper.

Combining all three of these - small pours, early in the day before it warms up, using an 'ester resin and minimal catalyst - would probably be the very best way to do it.

[atomvoyager]

I haven't done this job myself yet but I'd agree that poly resin is best here and I'd want to add some fiberglass inside where you cut away the keel for the shoe. Where did you source the bronze shoe? I'd like to do that on my boat and thought I might need to build a shoe from a stainless pipe welded to tangs.

[kenowens]

Thanks for the reply. Pete at Port Townsend foundary cast it for me from a mold he already had. It was not designed for the Triton but is looks bomb proof. The angle of the straps don't match my hull exactly so the forward end was resesed deeper exposing the void in the hull. I will lay up glass on the inside to compensate for the shoe notch as you suggested. I'll send you a picture of the mold when I get to my computer. Ken.

[kenowens]

The yellow RF-10 pattern is the one Pete used to cast my Triton's shoe.

[kenowens]

Hi everyone. I enlarged the hole under the rudder shoe slightly and probed up through the foam at 45 degrees. At 18 inches, the probe hit the underside of the false bilge. I welded a short extension on an 18 inch dill bit and drilled a hole at this angle. The bit emerged under the aft end of the battery box just beneath the companion way. To gain access and apply glass, I will have to remove the engine and the false bilge top between the engine mounts. Ken.

[atomvoyager]

On my Triton and the one I refit recently there is no false keel with foam or if there is it is small because I have about 28 inches from cabin sole to bottom of bilge. Apparently you have a shallow bilge version with a large foam fill area. Both of these are 1963 east coast Tritons with hull numbers in the upper 300s.

[kenowens]

On my East Coast Triton (Hull number 554) it measures 20 inches from cabin sole to the bottom of the bilge. There is only room for the bilge pump at the bottom and then the bilge slopes up to the stern tube.

The picture below is from the engine bay looking forward under the battery box showing the slope of the false bilge. If you look closely you can still see the drill bit piercing the false bilge through 18 inches of foam.

[atomvoyager]

From an earlier thread on Triton keels someone explained the false keel that is supposedly only found on pre hull #382 external ballast Tritons so yours must be internal with no false keel. If yours is internal ballast, either the factory or a previous owner must have added the foam and some glass above it. The good news then is that you have a very solid keel instead of the added false keel.

viewtopic.php?f=22&t=5792&p=48743&hilit ... eel#p48743

[kenowens]

The ballast lifting u-bolts protrude through the glass in the forward bilge. So my Triton is definitely internally ballasted. I suspect the foam was factory installed during layup since I can't see any tabbing on the false bilge bottom.

[kenowens]

After removing the battery box and the aft section of the cabin sole, I cut through the resin-rich bilge cover with a multitool. The glass was about an inch thick at the bottom and half an inch thick at the top. Here is the opening between the inboard engine mounts. After digging out the foam, you can see light coming in though the holes where the rudder shoe straps will be located.

[kenowens]

By the way, the foam smells strongly of diesel which must have entered the false bilge through its many surface cracks. The top of which seems to be pure resin. I am leaning towards removing the false bilge entirely, glassing as necessary to strengthen the shoe area, not filling the space with anything and painting.

[atomvoyager]

If it was my boat I'd cut out the remaining false bilge bottom, apply fiberglass and thickened resin as needed to support and seal the rudder shoe area and paint it all with white epoxy barrier coat Interprotect 2000e. The reason I use that in bilge, cockpit lockers and chain locker instead of a single part paint like Bilgecoat is because it goes on easily with a short nap mohair roller and is tough against chafe and water and can be glassed over in future if you decide to make further repairs and modifications such as adding an integral water tank into the otherwise useless aft bilge area. Two coats applied a couple hours apart covers well.

[kenowens]

Sounds right. Thanks for all the advice.

[kenowens]

The view facing aft between the engine mounts of false bilge removal project. It turns out that the remaining lip of false bilge surface can be snapped of with hammer and a chisel. I don't think I could do this if the false bilge surface was part of a hull/false keel joint.

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As a newbie, I still want to make sure that there is no joint and the hull was made in one piece. On the exterior, I scratched off the bottom paint above a spot where the hull/false keel joint would be but there was no sign of a joint. On the interior, I washed an area that I ground where the surface of the false bilge was (center of the above image and sightly to the left) and I am trying to make sense of what I see. I was expecting the woven mat from below to continue above the joint. Maybe it is hidden by resin the factory used to cover the foam in the false bilge. Below is a zoomed in shot of this area. Any comments would be greatly appreciated.

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[atomvoyager]

What we know about the construction history of these newer boats with internal ballast plus your own observations on the exterior confirm you don't have a false keel situation so that disappearance of the woven roving in the photo could be thickened resin on top of the roving. If concerned you could grind into a small area and see what you uncover and then add some glass over it. Or just add a couple layers of glass to the area anyway to help compensate for the glass joint you removed. In any case, you might as well add some glass in the lower bilge around the shoe and carry it up the sides as high as you want.

[kenowens]

Hi. I am trying to decide how to prep/layup glass inside the bilge to cover the holes I caused by mounting the rudder shoe. One issue is the glob of thickened poly resin above the holes seen in the image below. This glob provides a solid mounting point for the lower gudgeon (which I will not be using) but is in the way of getting glass on the hull surrounding the holes. Should I remove it? If so, any ideas on how to get rid of it? The forward edge of it is only two or three inches athwartship, making it difficult to get a grinder in there and it's three or four inches fore and aft. Any advice would be greatly appreciated.

PXL_20210617_230323111 (1).jpg (34.53 KiB) Viewed 409601 times

[atomvoyager]

If that glob of thickened resin is truly in the way and you can't just layup fiberglass over it then if a chisel is too short to reach you could take a long bolt or piece of rebar and grind a chisel point in one end and go at it with a hammer. The other option might be to apply thickened epoxy on the end of a rounded paint stick and fill the hidden area below it and then apply fiberglass over that, preferably before it hardens if possible to avoid air voids around another irregular blob of thickened resin. But either way it doesn't matter if you have some small voids since you will be sealing them in with layers of fiberglass anyway.

[kenowens]

Thanks for the comments. Glassing over the resin globs sounds right. However I had to figure out a way to prep them as they were covered by what I call peanut brittle. The peanut brittle is formed when the foam adhears to the resin. You can pry it off with a screw driver but it's tough. The resin globs have so much tecture that is is virtually impossible to get the stuff off. Below is a top-down view of the lower glob showing the stuff. A clear patch of resin can be seen in the middle where I chipped off the peanut brittle.

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After chipping away at the stuff, I thought why not sand blast it? I made a cheap DIY sandblaster from youtube. It is made from a harbor freight blow gun that cost a few bucks and has a notch that I filed in it to allow sand to enter. Sand is placed in the bottle, it is then capped and rotated around the nozzle to allow gravity to push the sand in the notch. Fire up the compressor and you are in business. The thing actually works!

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Here is the upper and lower resin globs after sand blasting

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PXL_20210618_215006662 (1).jpg (35.03 KiB) Viewed 409576 times

[kenowens]

For the past few days, fresh water has been seeping from the foam around the lead ballast into the aft end of the keel where I want to glass. Any ideas on how to speed up the drying process?

[atomvoyager]

Maybe someone else can give you an idea but meanwhile you could drill a hole inside and outside in likely spots and if it doesn't drip out fast enough drill more holes in other spots. Maybe try compressed air for the outside hole or a vacuum on the inside one. You could also try a moderate amount of heat under the keel after drilling. If you still have a slow drip you can build a temporary dam to stop the water getting to the aft area you want to work in or if the leak is slow enough, block the water with towels until the glass repairs cure. Should only take a few hours and then you can seal the entire bilge after the leak stops.

[CapnK]

Love the 'sandblaster' improv, that was a good idea.

And you have to love the things you see having been done (sometimes) in these old Plastic Classics - they are both history and a mystery, wrapped up into one giant FRP package.

[Ron]

I wish this trend would have been up before I built my water tank over that false keel. I don’t know if it helps any at this point but every body around here when it comes to rebuilding the Transum of these boats there using Sea cast. it comes in five gallon buckets you just mix and poor.

[Ron]

I’m right in the middle of adding a shoe on my keel. I’m having mine done at a fabrication shop with stainless steel with a brass bushing for the ruder shaft. Are you all thinking that the false keel isn’t strong enough to hold the shoe on with out filling it all the way up with epoxy. I don’t know how well it’s going to work but mine is going to be to plates welded to a bottom foot and through bolted on the bottom of the keel. Are you all under the assumption that it won’t be strong enough, just asking because if not I need to stop progress and rethink about doing it this way
Thanks

[atomvoyager]

I'm sure it will be strong enough but just to make sure you can grind the area outside all around within a foot or so of the shoe down to glass and add a few layers of fiberglass cloth before installing the shoe. If the shoe is already built and it's a snug fit as is and won't allow more glass under it then just add some glass over top of the shoe. That will also help fairing it in. Even though in future someone would have to cut away some glass to remove it, that's not a big issue. Maybe someone else has some idea?

[atomvoyager]

By the way, if you have an early Triton with a false keel, how did you fit an integral tank into the aft bilge since it was so shallow compared to my later model boat with internal ballast and deep bilge? I guess it was a different shape and location from mine?

[CapnK]

Hi Ron - I've 'seen' SeaCast and similar used with great success on power boat transoms, and so cannot think of any reason not to use it to fill in the keel area void, but...

That said, I agree with James - the original build method has been in use on hundreds of boats until now and working well for 50-60 years, so if that's what you have then there's probably no need to redo/restart your project in order to 'beef it up'.

I don't want to hijack Ken's thread, but a quick Q: With bronze and stainless in close proximity to one another - maybe you should have the fab shop weld a screw stud or two onto the shoe, for mounting sacrificial zinc(s) anodes..? Just a thought.
I'd like to see what they make up for you when you can post a pic.

[kenowens]

Hi Ron. If your new rudder shoe bolts up through the bottom of the keel, like on an Alberg 30, you are in luck! This area is very strong and three to four inches thick at least it is on my Triton. My rudder shoe bolts on from the side of the keel and I removed most of the glass under the shoe making a notch to mount it. In some areas I went all the way through the glass, so I have to glass inside to support the shoe. I'll post a picture showing you how thick the bottom of the keel really is. Ken.

[kenowens]

Hi Ron. Here are the pictures. I measured the thickness to be approximately 4 inches from the rudder shaft groove to the interior and the same from the bottom of the keel to the interior. The hole I put in my keel lets you see the inside and outside at the same time. Not good for keeping water out of the boat but it helps to see how thick the hull is. Ken

PXL_20210628_181304679 (1).jpg (39.03 KiB) Viewed 409373 times

[Ron]

James in regard to the aft water tank it wasn’t a very deep tank. I just followed the contour of the floor upward toward the back so you can’t open the front inspection plates without it being drained down a good ways if that makes any since. But the water tank reaches all the way back right in front of the Ruder shaft but still only holds about 25 to at the most 30 gallons at the most.

Great trend by the way thanks for all the information on the ruder shaft shoe, when I get mine from the fab shop I’ll post some picks of what we come up with.
I’m a novice with sail boats don’t know a lot about them but learning a great deal from you guys posting info thanks

[kenowens]

As I was grinding a taper in the glass joint where the surface of the false bilge was glassed to the starborad side of the boat, I noticed that a screwdriver slid easily under the glass. A little pressure popped off a big chunk revealing the same roven mat as lower down in the bilge.

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This is proof that the hull of Triton 554 was layed up without a false keel and an interior false bilge filled with foam was added later. Here is another pic of the same area after some more grinding. You can still see the false bilge joint on the port side of the stern tube.

PXL_20210701_220837800 (1).jpg (33.49 KiB) Viewed 409313 times

[kenowens]

Anyone know if these cracks are serious? They are on the starboard bilge wall and bottom of the bilge but not the port side. They seem to be superficial since they don't continue though the taper I ground in the glass on top of the ballast.

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[kenowens]

Hi. The delamination of the false bilge runs under the stern tube which is cracked both inside and outside the boat. Should I replace the it and gind out the last of the delamination?

[CapnK]

Hi Ken - Is the stern tube itself cracked, or just the glass around it? You are planning to repowering with an inboard?

The seeming likely bilge add-ons and those cracks, makes me wonder if she wasn't banged hard on some rock at some point, hard enough to require repair. I think I'd go ahead and grind them, then lay up some new glass there as it really won't be that much more work. I doubt that one layer of - what is it, 10oz or so? - glass will make a big difference, but you are there now with access and it'd be pretty easy to do...

[kenowens]

Thanks for the reply. The stern tube is solid glass. Is was turned down on the inboard end to accept a dripless seal, making it look like two pieces. Yes I plan to reuse the yanmar inboard. I will post a shot of the exterior portion of the stern tube when I get back to take boat.

[kenowens]

Here are some of the cracks on the exterior of the stern tube.

[kenowens]

I ended up replacing the stern tube. I used a router and a 60 grit flap sanding drum on a die grinder to remove the old tube, after first cutting off the exposed portions with a multitool. Since the stern tube is perpendicular to the deadwood, I freehanded a router to remove the first inch of the tube. The die grinder worked great on the rest since it could reach the entire length of the tube bore. The starboard side of the tube bore is the connected with the delaminated piece of fiberglass of the false bilge surface shown a few images above. The tube has voids on the same side as the delamination. I am thinking of grinding out the voids and the delamination. This would not remove any of the actual hull- just the delaminated skin interior to the hull which made up the surface of the false bilge.

[kenowens]

By the way, some of the voids in the stern tube bore had water in them. FYI here is the die grinder I used to remove the stern tube. The flapper drum began its life with a two inch diameter but prior use has worn it into this spherical shape. This shape was good for enlarging the 1.5 inch ID of the stern tube to 2.0 inches.

[kenowens]

Here is a closeup of the voids in the stern tube bore after cleaning out the sanding dust. When I shoot compressed air through one of the voids it comes out inside the boat beneath the delamination which you can see in the lower left corner of this image. I'm struggling with how to repair the delamination. Perhaps I could inject epoxy into the void to bond the stern tube bore with the hull? Any suggestions would be greatly appreciated.

[kenowens]

I decided to go ahead and grind out the stern tube bore voids (and delamination) since they essentially drain to the bilge. You can see the roven woving on the starboard side of the stern tube and in the image without the tube where the glass just popped off indicating that the starboard side of the stern tube bore was not bonded to the hull.

[kenowens]

In the previous image, the dark bands in the resin below stern tube opening indicate delamination. I got a new toy and continued to remove this damaged resin. Finally I ended up removing it all. The fact that you can see woven roving most of the way around the stern tube opening indicates that the tube was not well bonded. I will rebuild it with epoxy and glass to hopefully get a better bond.

[kenowens]

While prepping the bilge for glassing where the the rudder shoe pierced the hull, the bottom of the bilge needed to be sanded. Under the top two layers of mat was an inch thick layer of cracked resin. Chunks could easily be popped of with a screw driver. Underneath was the actual bottom. So, my boat's bilge has a bilge! Since I want to make a structural addition to the hull to support the shoe, I decided to remove this loose stuff. There appears to be some cracking in the roving on the bottom. This is the only place where I have seen any possible hull damage. I plan to remove the cracked resin from the ballast lead to the rudder shoe and to lay several layers of roving in addition to the 1708 I was planning to lay to strengthen this area. Does this sound sufficient.

[atomvoyager]

It does sound sufficient but if you want to add more strength against shocks from say hard groundings in waves then once you add the roving you can also add an inch or so of thickened polyester resin and then more glass on top using whatever resin you prefer. Overall thickness gives more strength than just a thinner section of just fiberglass.

[kenowens]

Thanks. I will rebuild as you suggest with thickened resin. The old resin layer does not seem to have been thickened. Perhaps the new thickened resin layer can also be strengthened by mixing in some chopped glass to prevent it from cracking.

[kenowens]

The good news is that sanding the bottom roving with 120 grit removed what I thought were cracks. It seems the "cracks" were print-through from the cracks in the resin just removed.

[kenowens]

The rebuild begins with some thickened epoxy and peel ply over the grooves in the lower gudgeon resin block to prep it for glass. You can see in the image three plugged holes approximately 1/4 inch in diameter. They were drilled through the keel by the previous owner and filled with wooden dowels. I assume these holes were drilled to drain the old false bilge. Two of them are vertical and their dowels can be seen at the bottom of the image. The third is horizontal through the starboard side of the keel and can be seen to the left of where I have folded the peel ply on a diagonal. Anyone have suggestions as to how to deal with these holes? Currently I do not have external access to the forward vertical holes due to the trailer but I can probably access the horizontal hole from the outside.

[atomvoyager]

I don't see why you can't do your repair of the holes from inside by either drilling out the wood plugs and filling the holes or leaving them in place and glassing over them. You didn't mention why you can't do that so I must be missing something here. To finish off the repair from the bottom you should be able to gain an inch or two of clearance between the keel and the trailer bunk board by using the screw pads to lower the bow and raise the stern. It's possible because the bottom of the keel is not flat. I always put two short 2x4 boards crosswise under the keel when setting the boat on the trailer so there is clearance for lifting straps, access for bottom repairs and painting but maybe you didn't do that for some reason?
What is the peel ply for? If you're using it to avoid amine blush or to smooth the surface for doing the epoxy work in stages with no sanding between stages, why not just do most of the work all at once, wet on wet layup. The thickened epoxy goes on and smooth it out best you can with some spreaders and then a brush with resin on it and then start laying the glass on top and as you press it down and wet it out it further smooths out the thickened epoxy underneath. I've never used peel ply in this type situation so not sure of the advantage. But again, not knowing your whole repair schedule, I'm lost.