Keel Bolt Repair Trailer Sailor

I'm not going real far on this, but the idea the floors would break on the ends first from the keel pressure is false. The keelson is probably a bit round. This means the greatest movement is at the middle. Make a c shape with your hand and thumb and forefinger and move your elbow as the keel; the hand moves through a greater range than do the fingers. The fingers basically stay in one place. Had the floors cracked further out; you probably would have lost the boat. They saved it..perhaps..

I do think the hull is probably fine, but I cannot in good conscience suggest you don't have a surveyor look at it. Nor can I support the idea of not repairing broken floors. Nor do I agree those cracks are not a direct result of the keel bolts being unsound and pressure from the keel acting on the keelson and hull unevenly. The keelbolts, if rotten in the middle as they appear also explain the cracks through occam's razor, the keelson is rotten here, the floors did too much work, etc.

I am sorry to tell you, but posts like yours are not well received on the forum. Most of the better trained members avoid posts where they become concerned about liability a/o if the poster seems like they won't listen. The last thing anyone here wants is a tort claim after 3 people drown on a boat because someone jerry rigged a repair, not to mention the frustration of an owner in denial about floors cracking, etc.

See if @kapnD replies here again or is willing to comment on the floors being cracked.

The floor I blue arrowed at the bottom looks like has had other maltreatment or has other holes plugged. This would also weaken it and help it crack under keel pressures. It needs replacement I'd say unless the patches are fooling me. They could have even contributed to the cracking. Not all that hard to do the floor repairs really. If you don't believe the timbers cracked or are deficient, grind the mat and resin off the tops and inspect.

Where is the boat? I am in Inver Grove and slip at SPYC in a month or two.

By the way, the floors do not look like they were ever that strong, on this we agree. So if you redo them, you may consider making them a bit higher.

 

What are x, y, z?

 

If I recall correctly, X is a piece I cut out to look under the crack in the CSM cap on the floor, Y is the removed piece, Z is the dust from removing the piece. I saw your comment up-thread about maybe looking at the floors under the cracks at greater length and agree that would be good. We agree that the boat needs to be evaluated and repaired properly.

 

Here are some more pictures and words.
- a shot through the companionway showing the 3' x 4' (.9 x 1.3m) area of interest.
-peeling back the 3/16" (4.5mm) CMS and polyester tabbing to see the 3/4" (19mm) plywood pieces
-floors, 2" (50mm) x 36" (.9m) rest on top of keelson 6" (150mm) x 48" (1.3m) with 1 screw and the inner junction was 'hollow' and not glassed, adding places for water ingress. One floor had a tab that was not bonded to the deck for 3-4" out from the keelson, a known leaker, close to the companionway, on the side with the black cord.
-some of the CSM was not fully wetted out and qall of the plywood is damp.
-the thin cap removed by the hole saw previously mid-floor seems to be atypical, the rest of the tabbing is thicker and a bit lumpy to boot. Being thinner in some spots might explain the cracking as well.

 

Actually, that poly resin is not strong enough to withstand wood swelling. More likely than the keel breaking plywood, the wet wood exploded the floor tabbing. I had assumed the floors were timber which should not have cracked. But understanding saturation changes my perspective,

The plywood, clearly compromised, needs to be removed.

I recommend you remove all the polyester covering the floors. Evaluate each floor for being saturated.

It isn't great news, but it offers good relief that the hull is okay.

The greater concern now is the keelson. It looks pretty rotten and is likely also soaked. The keel probably needs to come off for the work, and the keelson and floors replaced.

See little need for surveyor now. Looks like you got a very wet boat.

 

I am in Minnesota. Where is the boat? I might even have some materials you can use. I have some 8" 1708 tape iirc that would work well for the tabbing of the floors. They are used with epoxy all the time.

And I definitely think I'd repair with epoxy.

You don't need to use plywood, but you'd need to make sure the keelson and floors are strong as the plywood. Otherwise, you might be able to source 18-20mm okume from my friends at bbc in Florida. They might even cut pieces to reduce the shipping.

Also, if you use timber, you need to make sure the grain orientations are correct.

Might be some challenges getting the holes right in a full replacement. Keeping the keelson in one piece when removed will offer close holes.

Might need another forum member here help with the lineup. I guess all from the outside and drill with a long bit with the keel supported somehow.. At 500#, gonna need a jig maybe.

@bajansailor

Care to comment? I think you are out of reach on liability.

 

Thanks for the comments and ideas and the offer of materials Fallguy. I am near Cannon Falls, so not far as the crow flies.

Need to run for tonight.

 

Settling in to the notion and formulation of steps to fixing this.
Some questions:
1. Put some bracing across the beam at berth level before pulling floors? Berths are tabbed to hull and screwed to the two tall longitudinal's that span the space.
2. Brace back down from above supports to the hull between floors? Or make mini-bulkheads temporarily glassed between floors to maintain hull shape? Not anticipating alot of movement but don't want it to go 'sproing' either...
3. Is there a rule of thumb that x amount of CSM+polyester resin can be replaced or superseded by y amount DBM 1808 (18oz/yd biax knit+/45 w/ epoxy-compatible mat, 24oz/yd total) and epoxy resin?
Thanks!

 

I might leave the keel in place and use it for the bracing. Obviously, the keel would need to be well supported with wood timbers.

I have not ever replaced a keelson, so I am a bit hesitant to tell you precisely how, but keeping the keel home would support you working inside.

When the structural members are all removed, the only thing holding the keel would be your bracing, so it would need to be done real well.

That same bracing could support any additional you deem needed.

Boat work is pretty artsy for this sort of repair. I don't feel exceptionally qualified to spec a layup for you. Something on the order of 3-5 pieces of 1708 or 1808. The pieces would be staggered, so the first piece would be say plus 4" each side, next piece plus 3", next plus 2" or so. Long is first in this repair. Short first is substandard.

Epoxy would not be needed, but the repair is not massive, so I hardly see reason after all the work needed to use esters.