Protecting end grain against moisture

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jbo_c
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Protecting end grain against moisture

Post by jbo_c »

What do you do in areas where end grain is unavoidable? I’m specifically referencing the top of my transom. I’m obsessing over making sure it’s sealed well enough. Could be making much about nothing. Debating adding a layer of light glass on the top, not for strength, but to make sure I have a thick enough epoxy layer there to protect it adequately. But at the edges,I’m guessing it will still be fairly thin.

On another boat, I made a ‘dam’ with tape and poured a thin ‘glue’ style mix in to make a near fully epoxy cap. That was surely overkill. :)

So, I guess I’m overthinking, but what do you do?

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Jaysen
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Re: Protecting end grain against moisture

Post by Jaysen »

Neat epoxy, 2oz or 4oz glass, thin fairing, prime, paint. If you’re still thinking about it, sell the boat because you’ll always know it’s there.

Seriously… every hole has the same problem. Are you concerned about every stitch point? Probably not because … epoxy, glass, fairing, paint. Maintenance of edges is what keep the water out as much as the prep. So routine clean, inspect, repair is where your peace of mind should be found.

Hope that makes sense.
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Fuzz
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Re: Protecting end grain against moisture

Post by Fuzz »

That spot is bad for rot to set in. I am much happier with a layer of glass over it. If you already have things painted your dam and pore idea would help.

OneWayTraffic
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Re: Protecting end grain against moisture

Post by OneWayTraffic »

Round the top edges and glass with 12oz if it's a powerboat transom. The transom is critical, difficult to replace, and always exposed. It needs to be well protected.

For other edges I'd prime with neat epoxy, then thicken the gelled epoxy left in the cup and push that in with the mixing stick. Fair next day if needed, and then a coat of neat epoxy over the fairing if needed.

jbo_c
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Re: Protecting end grain against moisture

Post by jbo_c »

I did sort of a blend of “dam” and glass. Primed with epoxy, then did a layer of ketchup and embedded glass. Will fair with Quikfair.

Jbo

TomW1
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Re: Protecting end grain against moisture

Post by TomW1 »

You need to put a layer o fiberglass tape over the top of the transom.
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fallguy1000
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Re: Protecting end grain against moisture

Post by fallguy1000 »

Radius and glass plus 2”, minimum one 12 oz biax or say 3 6oz woven; I’d use staggers for woven like 2”,1.5”,1”

Transom ply will split wide open otherwise, due to varying cte of the glues and wood grains. (Heat and sun)

You can square it back off with fairing compound if you like the beefier look.
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