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Protecting a Wooden Keel Strip


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well, I have to admit that I did‘nt try this. I‘m only thinking/fantasizing. 

And this is what comes to mind: 

If it’s badly damaged, you can pull it off or grind /sand the remains away.

If it is not badly damaged, you can leave it as it is - or give it a coat of epoxy - or patch it up with some similar stuff.

No big deal in any case.

Of course, some metal strip would be much more durable. But also much more work and cost. And the problem of how to fasten it - as this thread shows.

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That’s my biggest problem with most screwed-on parts.  Realistically, this boat will be wet approximately three hours per week, so it shouldn’t be a problem.  But I’m also thinking about other applications.  When we go camping, for example, I take my nesting pram.  I like to keep her in the water for the entire time I’m camping.  Screws might begin. To be a problem here.

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My nesting Spindrift spent 2, 6 month seasons in the water at the dinghy dock and several seasons in and out.  I still have yet to notice a single issue with the fastening into the keel of my chafe strip.  I think someone has scared everyone here about fastening.  Clean the mating surfaces and bed everything well in a good, mildly adhesive bedding compound. Then go sailing.

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2 hours ago, Hirilonde said:

I think someone has scared everyone here about fastening.  Clean the mating surfaces and bed everything well in a good, mildly adhesive bedding compound. Then go sailing.

 

 

Well said- bedding compounds work well

As far as the keel itself I consider it  sacrificial- if it rotted it's isolated from the hull by epoxy and glass and easily replaceable. I'd call it a wormshoe of a type.

I used an aluminium extrusion on the keel strip which was very inexpensive (mainly to spread the load from the rollers). I didn't extend up the stem so no one sees it. If you want classy then pay for bronze.

Cheers

Peter HK

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For the paranoid, you could drill an oversized hole where each fastening will be, fill with thickened epoxy, then the screw taps into the epoxy. But I agree with the comment above- probably unnecessary, especially for boats that spend little time in the water.

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Y’all are probably right about screws, bedding compound, and paranoia.
 

Tell me about using brass in salt water.  I’m a Lake Erie boy, and I need an education.  I have a piece of oval brass, like the kind used on canoes.  Is brass OK for occasional saltwater use?  I’d like to use it on the stem as protection from aluminum docks and trailers.

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You can use brass in saltwater but it won't last forever, and it may discolour and de-zincify, rendering it soft and crumbly. For occasional use it will be fine.

Brass through-hulls were approved under the EU's RCD regulations, meaning that they can be expected to last five years.

Bronze or stainless would be better choices but I wouldn't lose any sleep over it.

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H OK, boys and girls, here’s the latest. Several good suggestions were made here and elsewhere on this forum.  So as to not delay my build, I’m going ahead with Dynel. But how will it perform?  Would another method be better?

 

When I was a working lad, I was an automotive engineer in the interior engineering department.  The fabrics we used for seating and elsewhere were required to pass an abrasion test— the Taber test, as specified by ASTM.  (I forget the spec number, so shoot me!)

 

I woke up early a few days ago with an epiphany— let’s make some test samples, subject them to identical test conditions, and see how they perform!  
 

I applied my Dynel today.  While I was at it, I made four test samples.  Two were a thick and thin nylon webbing, one was glass tape, and the fourth was Dynel.  I’m thinking that the abrading device might be a belt sander, with a 2# weight applied to the sample.  Which grit should I use?  Currently, the belt sander has 60 grit on it.  Might be a tad coarse.  120?

 

The first photo is my Dynel.

 

 

 

 


 

 

 

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Our Core Sound will be at the Messabout, take a look at our keel strip.  It is unidirectional glass fibers set in epoxy (with some graphite powder). 5 years and holding up ok.  Abrasion isn’t a problem but as I mentioned earlier point loading might be not as good.  I think you will like your keel strip Don. 

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"White Oak has a reputation of “letting go” of epoxy"

 

I feel like this is not supported by any meaningful data. I've used quite a bit of white oak, epoxied to stuff over the years and have never had a failure. It is closed cell, but not particularly oily. I do take precautions and rough it good.

 

Has anyone ever seen this?

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3 hours ago, Steve W said:

"White Oak has a reputation of “letting go” of epoxy"

 

I feel like this is not supported by any meaningful data. I've used quite a bit of white oak, epoxied to stuff over the years and have never had a failure. It is closed cell, but not particularly oily. I do take precautions and rough it good.

 

Has anyone ever seen this?

I think the ellusive meaningful data you speak of was collected by the same guy who says you can't epoxy teak and there is no good way to fasten things that will be under water.

 

Gluing is in the prep.  On top of the rough up, clean the mating surfaces well with acetone or alcohol (acetone is better) and get gluing.

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Graham Byrnes cringed, when I told him I used it for my keel batten and stem.  He used the term “letting go”.

 

I also learned that System Three was developing a product for certain woods.  It is G2.  (See photo.)

 

I also have a dinghy that I built in 1990. It was built of fir plywood with a white oak stem.  The plywood is a poster child for checking, but the bond to the stem is solid.
 

Suffice it to say that it is like mask-wearing these days.  Some do, some don’t, but there’s a risk involved.  I was simply sharing what I learned from two respected sources.

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Here’s a photo of the old dink.  This photo shows how well the joint has held after 30 years.  But I am sure that there’s is a solid basis for Graham’s feelings on this.  
 

This photo also shows “death by checking” in progress.  

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