Bad News - Wet Balsa Core

[Cheechako]

Is it possible to remove from the under side avoiding all that repaint etc?

[arthur.watson.1]

<<Know of anyone in the Beaufort-Oriental, NC area who is really good at that sort of thing?>>

I believe the "Sailcraft Service" yard near Oriental could do this easily for you. They are capable and professional. We had a god experience with them in 2014.

[Suijin]

Sailcraft Service, in Oriental. I'm there now finishing my refit. They can certainly do the work that you need. Nice, knowledgeable folks and work gets done when it's promised.

If it's just the floor the cockpit it would probably go quickly and take a few days. Cut out the skin with a Fein saw, recore with foam, put the skin back down with epoxy.

[UNCIVILIZED]

An easier fix than removing skins, scraping out old core etc., is to remove the entire cockpit floor. Laminate a new one off of the boat, so that both sides are glassed, & pre-finished but for the edges. Bond it in place, typically from below, then adding filets & cloth around the edges from above. And then paint or gelcoat it around the edges.

That, or cut out the old sole, leaving enough of a lip of bottom skin so that you can just drop the new sole onto the lip. Then bond in place, etc.

[hellosailor]

AJ-
Look online for Wally Bryant's heavy rebuild of a C&C Landfall 38 named "Stella Blue". Among the many jobs he did (in truly Bristol fashion) was a rebuild of the cockpit sole, for very much the same reasons. It may give you a better idea of the specifics involved.

[ghendoaus]

Also you could watch Mads from sail life as he has undertaken to replace his entire deck core on his Warrior 38.
Latest video here Sail Life

His step by step approach is easy to follow. Also Andy from Boatworks Today has a great series on core replacement. Boat Works

Hope this is helpful.

[Terra Nova]

Originally Posted by Suijin

...put the skin back down with epoxy.

Not quite. You would still need to glass the old skin to the cockpit liner around the edges.

[DeepFrz]

Originally Posted by AJ_n_Audrey

Thanks, good input. Because of the extremely tight conditions under the sole, it may or may not be possible to cut and remove the belowdecks portion. I'll just have to evaluate. An easier approach may be to cut with a dremel along the edge of the non-skid on the topside of the sole, replace balsa with other media, glass, replace, try to make it look pretty.

I think you have it right. Much easier to do it from the top, IMO. The West Systems web site has information on matching deck repairs in case you didn't know of that site.

Good luck.

[GordMay]

Originally Posted by hellosailor

AJ-
Look online for Wally Bryant's heavy rebuild of a C&C Landfall 38 named "Stella Blue". Among the many jobs he did (in truly Bristol fashion) was a rebuild of the cockpit sole ...

➥ Cabin Sole

[TheThunderbird]

Dremel?? It is a toy-machine.

[minaret]

If you go from the top, consider laying out your cut about 2" inside the non skid line. Then triple tape the smooth with preservation tape. Make your cut, remove core, decore the margins, grind for prep, recore the margins, recore the center, reglass top skin, rough fair and apply nonskid. No finish work required. Done it many many times. Yes to Coosa for core.

[ramblinrod]

Originally Posted by AJ_n_Audrey

As I was replacing the access cover for the steering quadrant, I got an ugly surprise: whoever installed the existing access (which is not original to the boat) port did not glass around the rim, so water has been getting into the cockpit sole for years. Borrowed a moisture meter, and, yup, the entire sole is wet, wet, wet. So now I have another project.

The binnacle will have to come off, and then cut the sole out with a dremel saw, scrape out old balsa, replace, glass, etc, etc. Kind of pisses me off - I've had the boat for two years, and while the pre-purchase survey did find a few limited wet spots on the deck, the surveyor said nothing about the cockpit sole. Oh well.

While I would like to do this myself, or with a little experienced help, I am limited on time available to get the boat ready, and given the other projects in queue, I may want to pay to have this done.

Any idea how much a job like this would cost? Know of anyone in the Beaufort-Oriental, NC area who is really good at that sort of thing?

Be careful to properly evaluate before beginning extensive, expensive repairs.

How wet?

Bone dry is obviously preferred, but in any boat more than 20 years old that has not had all fittings removed and rebed, this is highly unlikely.

Saturated rotted core may be a problem. Slightly damp core is really no problem at all.

Is there any soft spot or delamination?

How far does it radiate from the source of ingress?

Moisture meter readings (the actual value) don't mean a lot on there own.

First you have to be careful you are not reading metal under the cockpit sole (like the quadrant).

If the core is truly elevated (moisture wise) you need to determine how elevated.

If dry core reads "15" and saturated core reads "100", then anything below "75" is likely a non issue (as long as you stop further ingress).

Do some 3/16" core samples in various spots that represent different readings radiating from the source.

Water squirts out when squeezed between fingers is bad. Just damp (won't leave a damp spot on a paper towel when squeezed really hard against it) is usually a non-issue.

My guess, if the access was only installed 3 years ago is that there is no (or little) rot / delamination.

In that case, gouge out the wet balsa as far as you can reach from between the skins. If you move from saturated core to just slightly damp core, all you have to do is train a blow dryer (or heat gun on low) around the perimeter of the gouged out area to dry the surface of the exposed core, flush with (danger flammable) methyl hydrate (to kill any rot and extract more moisture), drain and allow to evapourate dry, brush in some thinned resin, followed by push in some thickened resin. (3 or 4 hours and $20 in materials.)

Which leads us to..."Every cored FRP penetration should be resin potted to begin with. No exceptions, no excuses."

[Terra Nova]

Originally Posted by ramblinrod

...Slightly damp core is really no problem at all...

Come on!

[ramblinrod]

Originally Posted by Terra Nova

Come on!

Seriously, there are very few cored boats over 20 years old that don't have some moisture ingress.

[Suijin]

Originally Posted by Terra Nova

Not quite. You would still need to glass the old skin to the cockpit liner around the edges.

Well it's a question of whether he's going to try and repair and match the existing gelcoat (if he has gelcoat and not paint), which would be a huge job with that much of a patch. If paint is in the future, I would do the whole job in epoxy, probably using biax along the edge of the cut skin for the repair. Honestly would probably be easier (and a better quality repair) to put new glass down on top of the new core. Getting the old skin back down without voids would be a chore.

It's one of those jobs where the demo and basic reconstruction takes 30% of the time and 60% goes into making it look good.