Cracks in keel

[SailingLoto]

I was scraping bottom paint on my boat today, enjoying the warm 38 degree weather. When I came across a odd looking spot on my keel. The boat is a Laguna 26. The keel is encapsulated. It covers the rear, stbd corner going up and forward about 18". Lots of decent sized, deep cracks in the gelcoat, some getting fairly wide. It also has these half dollar sized pock marks in the glass. Is this an old or possibly factory repair?? I drilled four .25" exploratory holes in it and got no water draining out, so it's not a wet/frozen keel. The glass was dry , about 3/8-1/2" thick depending on the spot.

I guess I will be breaking the grinder out this week.

 

[BarryL]

Hey,

I can't be 100% sure from looking at the picture, but I think you are just seeing many old layers of bottom paint. My suggestion is to use a scraper and scrape, scrape, scrape away until you get down to gelcoat, epoxy, or metal.

Good luck,
Barry

 

[Scott T-Bird]

I don't know anything about encapsulated keels, but are you just looking for something to do? Unless there were actual chunks of gelcoat or fiberglass coming loose around the trunk, I think I would be inclined to simply sand the keel and coat it. Do you think there is any danger that the keel would be displaced? I don't really know how an encapsulated keel is secured, so I would look into that first before doing any more significant exploratory. The blue is obviously paint. I can't tell about the brown … it almost looks like years of pond scum.

If you sand down to gel coat and the hairline cracks persist, before grinding, I would do research to find out if the cracks are significant and if not, simply coat the bottom, probably with epoxy paint.

 

[kloudie1]

Yeah, kinda looks like a fairing compound that is failing.. someone may have used an automotive filler (Bondo?) in the past.. also might be layers of old non-ablative bottom paint.. Apply a scraper to get to the bottom of the problem
It doesn't look structural.

 

[dlochner]

I'm in the "It looks like fairing compound" crowd. Polyester based fairing compounds, especially cheap ones like automotive Bondo tend to shrink over time, become brittle and crack. Add some water to the mix and a freeze-thaw cycle or three and the resin cracks.

Pick an area and chip and scrap to see what you find. I doubt the cracks extend into the glass.

 

[LeeandRick]

Is that section hollow or have ballast? If it's the hollow section it may have become concaved over the years and faired. Pick a small area and start chipping until you find gelcoat or fiberglass mat.

@Scott T-Bird Encapsulated keels are normally a part of the hull mold and ballast is added from the inside and sealed.

 

[sail sfbay]

Suggest grinding off everything to bare metal keel, then apply new barrier coats (7 coats of epoxy) when dry followed by anti-fouling paint.

 

[shemandr]

I'm in the not structural camp. As unpleasant as it will be I'd take it down to gelcoat or even fiberglass and rebuild it smooth. Smooth is fast. Sailing is a kinetic sport. A smooth bottom makes the boat move better and adds to the enjoyment. An absolute must!

 

[Don S/V ILLusion]

There are a couple ofLaguna 26s on the hard at the local sailing club in Sarasota which have been for sale for a while. Both have hung iron keels - not encapsulated. And both exhibit similar cracking last time I noticed.

Assuming yours is as well and someone botched prior repair jobs, water can easily penetrate causing oxidation (rust) which expands thereby causing these cracks. Simply fairing whatever you may use to cover it won’t stop recurrence unless the oxidation is treated.

 

[dlochner]

Suggest grinding off everything to bare metal keel, then apply new barrier coats (7 coats of epoxy) when dry followed by anti-fouling paint.

It is an encapsulated keel. If the fiberglass is ground off, the ballast will fall out. Don't wanna do that!

 

[SailingLoto]

I'm going with your previous post... I looked into it more closely and there is a thin layer of what appears to be polyester filler under gelcoat. I think it's and old repair, possibly factory as it has the same layers of brown and blue paint over it as the rest of the boat. I will grind it out this week and verify.

ballast appears to be iron set in resin. zero signs of any rust where I drilled it. I was happy to see that.

 

[SailingLoto]

I don't know anything about encapsulated keels, but are you just looking for something to do? Unless there were actual chunks of gelcoat or fiberglass coming loose around the trunk, I think I would be inclined to simply sand the keel and coat it. Do you think there is any danger that the keel would be displaced? I don't really know how an encapsulated keel is secured, so I would look into that first before doing any more significant exploratory. The blue is obviously paint. I can't tell about the brown … it almost looks like years of pond scum.

If you sand down to gel coat and the hairline cracks persist, before grinding, I would do research to find out if the cracks are significant and if not, simply coat the bottom, probably with epoxy paint.

I was scraping 35 years of bottom paint off and came across it. No other places on tbe keel or bottom have any cracks, so something has happened there.

The brown appears to just be more old bottom paint, and the original color.

 

[SailingLoto]

I'm in the not structural camp. As unpleasant as it will be I'd take it down to gelcoat or even fiberglass and rebuild it smooth. Smooth is fast. Sailing is a kinetic sport. A smooth bottom makes the boat move better and adds to the enjoyment. An absolute must!

that's the plan at this point. Not going for speed. I just like to know it's fixed before it's in the water and I can't see it.

 

[higgs]

I would definitely not grind this down to bare metal as was suggested. Many encapsulated keels are not bolted to the hull so if you grind away the fiberglass there will be nothing supporting the keel.

 

[Ken Cross]

I'd grind it down and put a few layers of fiberglass on it. If you keep it on a trailer, just follow it up with a good 2 part paint. If you keep it in the water, follow up with barrier coat and bottom paint.

 

[Don S/V ILLusion]

I'm going with your previous post... I looked into it more closely and there is a thin layer of what appears to be polyester filler under gelcoat. I think it's and old repair, possibly factory as it has the same layers of brown and blue paint over it as the rest of the boat. I will grind it out this week and verify.

ballast appears to be iron set in resin. zero signs of any rust where I drilled it. I was happy to see that.

don’t want to “burst your bubble” of happiness but you probably drilled right thru any rust that may be there. Not to mention a 1/4 inch hole may be representative of nothing.

You have the opportunity to examine the structure now instead of wondering for months later.

 

[Scott T-Bird]

@Scott T-Bird Encapsulated keels are normally a part of the hull mold and ballast is added from the inside and sealed.

That's my thought … if it is really encapsulated, I wouldn't be grinding away the outer layers for an exploratory mission. You could just be grinding your way into a solution that costs way more than the boat is worth. I'd get all the paint and crud off down to gel coat and determine if the keel is secure or not. If it can be determined that the keel is secure, I'd simply coat and seal the exterior and go sailing. If it's not secure, well, I don't know if it would be worth the repair or not. Figuring that out would be the next step.

Just reading about encapsulated keels, I don't really get what would be the reason for fairing compound?

I probably wouldn't be spending the time scraping, either. Sand blasting, (or soda blasting) would make short work of it.

 

[dlochner]

Just reading about encapsulated keels, I don't really get what would be the reason for fairing compound?

Molding an encapsulated keel is a little challenging. There is not a lot of room to work and it is awkward to get to. So, their might be some imperfections from the lay up or from removing from the mold. Or there might have been some damage to the keel from a grounding or striking a submerged object. Or a PO might have trie to get a better shape on the keel. Who knows.

 

[SailingLoto]

If thr weather holds, I may dig deeper tomorrow night.

Thank you everyone for your input! I do not think it is structural. Everything looks, feels, sounds solid.

I noticed a couple comments questioning why I scraped it to begin with versus soda blasting or sanding and repainting. The bottom paint was literally falling off... 4+ layers of old dried out bottom paint. I stripped it this far in about 3 hours with a 4" razor scraper.... It was super easy and fast, with near zero investment other than time.

 

[dlochner]

If thr weather holds, I may dig deeper tomorrow night.

Thank you everyone for your input! I do not think it is structural. Everything looks, feels, sounds solid.

I noticed a couple comments questioning why I scraped it to begin with versus soda blasting or sanding and repainting. The bottom paint was literally falling off... 4+ layers of old dried out bottom paint. I stripped it this far in about 3 hours with a 4" razor scraper.... It was super easy and fast, with near zero investment other than time.

For a small boat, soda blasting or other removal methods may not be cost effective unless the marina can do it onsite. If a contractor has to be brought in the cost may exceed the boat's value. Scrape on! Get a file and keep the scraper sharp. You may want to take the sharp corners off the scraper to keep it from digging in and scratching the glass.