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ghoti
02-16-2010, 05:52 AM
Hi all,

Long time reader, first time poster here..

As part of an ongoing project I am removing a glass sheath that has delaminated from a cold molded cedar hull (internal). I am getting some help and advice from a local shipwright but given the work I am about to embark on I would like a second opinion.

His thinking is that although the glass was never properly bonded to the hull it was a silly idea in the first place given the risk of water ingress and the better bet is to remove the glass and put down numerous coats of everdure.

I will be doing the work myself and getting some assistance with the final prep before it goes down.

It makes sense to me but given the penetration qualities of Everdure I am keen to hear other ideas.

The hull itself is in good nick and I want to ensure it remains so for another 30 years.

30ft Cold Molded Cedar Nantucket (Plug Boat)

Any thoughts or comments on his proposal?

Thanks,
Alex

chuckt
02-16-2010, 08:14 PM
Do you mean it is on the inside but not the outside? Call the technical guys at West Gougeon. They are very knowledgeable. I am guessing they would suggest outside and inside glassing for a cold molded boat but probably not inside only. I do know that even on a cold molded bottom, you have to make sure everything is done correctly if you are going to glass. Too much moisture from somewhere and you will have issues.

bmhogan739@yahoo.com
02-16-2010, 09:32 PM
In the beginning of my career I worked with California Custom Yachts. We specialized in cold molded hulls. We always coated the exterior of the hulls with a layer of 4 oz. glass without any delaminating. The trick is, as Bob Perkins always said, seal the last layer of veneers thoroughly while faring your hull and do not go sparingly with the epoxy when applying the glass.

I sheathed the 28' Herreshoff "Zephyr" with epoxy and mahogany wedges in all the seams and three layers of 1/8" mahogany veneers. The last layer was run fore and aft with a layer of 4 oz. glass. As with fiber glass boats, there was some spider cracking in high impact areas.

The strength of cold molding is the epoxy bond between the alternating layers and must be sealed inside and out. The inside would get a healthy coat epoxy under the primer and paint.

have fun

Bruce

ghoti
02-17-2010, 12:27 AM
Hi,

The outside is sheathed soundly, my issue is inside the hull where a non-original glass lining was put in the bilge i am guessing to try and protect it, It comes up about a foot from the bottom of the bilge.

I have removed most of the glass back to the hull timber which looks and feels sound and dry so the question is to follow his advise and use a penetrating goup such as everdure of consider re-lineing the hull with glass.

Thanks,
Alex

bmhogan739@yahoo.com
02-17-2010, 09:43 AM
I am using the WEST System. The bilge must be dry, then I would clean it out sanding and scraping if needed. Then vacuum area. Apply a light coat of epoxy, watch of air bubbles and brush out bubbles. Then once area is at preset (still tacky ) re-coat with epoxy.Let epoxy kick then sand out any needed rough areas and scratch sand entire epoxied area and brush final coat of epoxy. This seals the bilge, a paint coat will make it easier to keep it clean and keep an eye on it.

If you reline with glass and the boat is cold molded with WEST system epoxy the problem maybe that is was lined after is was built and the used polyester resin to saturated and bond the glass. however polyester resin do not stick to WEST system epoxy. If you've cleaned down to bare wood you should be ok to reline with fiberglass using any epoxy resin.
Bruce