View RSS Feed

trickdhat

Time to come clean...Identifing rotten core

Rating: 1 votes, 5.00 average.
The past few months I've noticed I've become of consumer of this page instead of a contributor. Although I check the page often and am actively working on Luffalee, I haven't posted much lately. One of the best things about this community is its made up of real people with a shared interest, not professional shipwrights writing articles on the absolute best way to compete a task. The result is a resource that's inclusive, a community that celebrates success and helps us laugh off failure. I know this, but for some reason, I've felt like I had nothing to offer because I was just stumbling through my repairs and making way more mistakes than I care to admit. Well, it's time to come clean and maybe I can help someone else realize they're not the only one...or at least give someone a laugh and make them happy their not in my shoes.

I knew I had core issues when I bought the boat. All the evidence was right there the moment I pulled back the headliner zipper, but it was a boat, it was within grasp, and it was one of those boats you always look back at when your headed home at the end of the day. I told myself, "maybe they used different resin in high stress areas", "it's normal to have a little water in the core", "all boats this old have issues like this, I can fix it". There's probably a little bit of truth in all those thoughts (ok, definitely not the resin idea), but regardless of what got me in this situation, its time to fix it.

I started the repair last year when I was waiting for the epoxy barrier coat to tack up before putting the first coat of bottom paint on. I climbed up and started removing the cabin top hardware in an attempt to rebed it and seal some of the leaks. A few bolts later, and all doubt was removed. I had a core issue. water was dripping from the holes as soon as I removed the nuts. The core was mush under the cabin top winches, clutches, and cam cleats. I wasn't sure how far it went at the time, but it wasn't good. I used my Fein Multimaster to cut away at the bottom skin on the port side of the companion way. There was nothing left bonding the bottom skin to the top. After cleaning up the underside of the top skin, I noticed a few things;

1.) The core wasn't bonded very will in the first place. It looked like they builders ran a few streaks of resin along the top skin and placed the sheets of bulsa without spreading the resin around. This also created long voids that ran along the whole length of the cabin top.

2.) There wasn't a fillet along the edge of the core, so the bottom skin created a long void along the edge. Any water that got into the core was free to travel along the edge once it got down that far.

3.) the areas behind the raised companion way slides weren't filled. The balsa was just placed over the void. there were plenty of other places for water to get in, but I'm wondering if part of the problem was moisture from the cabin condensing on the bottom of the companion way slide and dripping down on the top of the core.

4.) All of the screw holes for the teak trim keeping the companion hatch secure were drilled into the core. I understand owner installed cabin top hardware being a source of leaks, but its a shame Ericson took so much effort in ensuring the chainplats, T track, and other hardware wouldn't leak into the core while drilling a dozen holes on each side directly into the core.

5.) The bottom skin is much thinner than the top and looks like it is just CSM. This was one of my deciding factors in choosing to go from below instead of opening up the top. The bottom skin didn't seem to be strong enough to hold the shape while going from above. There also wasn't a noticeable flex in the cabin top while walking on it even though the core was completely rotten and there wasn't a bond to the bottom skin. It's almost like the top skin was thick enough and strong enough to provide the stiffness necessary.

To get sailing, I removed the rest of the cabin top hardware, rerouted the running rigging to the starboard side and started asking around for ideas on a repair. That got me through the rest of the season and we took trips to the San Juans, Seattle, Langley, and Port Townsend as well as many day sails.
Name:  IMAG1981[1].jpg
Views: 201
Size:  68.0 KB
to be continued...

Submit "Time to come clean...Identifing rotten core" to Digg Submit "Time to come clean...Identifing rotten core" to del.icio.us Submit "Time to come clean...Identifing rotten core" to StumbleUpon Submit "Time to come clean...Identifing rotten core" to Google Submit "Time to come clean...Identifing rotten core" to Face Book

Categories
Uncategorized

Comments

  1. frick's Avatar
    WOW... my 1971 E29 has had very little core rot. Also I have a Fiberglas headliner so you can see most of it even if you wanted to.

    For me, it has been small things.... A bolt hole... or in one spot, and 1 1/2 bubble in the foredeck... It turned out to be a little glass de-lamination. It was fore of the Vee Berth bulkhead... So I used a hole saw and cut it our, and put in a SS Waste Deck pump out port.


    Rick+
  2. frogwraps's Avatar
    I recently purchased A 1983 E-38 with the same problem. Knowing this upfront and expecting a sizable job I have researched this to great extent. I just Put her up on the hard two weeks ago to rebed the keel and rebuild the mast and rigging. I also will be attacking the cabin top rot issue. I also have rotten decks. I think I have come up with an ingenious solution. I haven't tried it yet but it is drilling holes and de coring it from the inside and then injecting structure expanding foam back in without opening up all the way. would love to talk more about it. I just finished my cabin sole.
  3. trickdhat's Avatar
    There's definitely a few things I've placed on my boat to reuse or avoid repairing a hole. The waste pump out sounds like a great solution.
  4. trickdhat's Avatar
    Quote Originally Posted by frogwraps
    I recently purchased A 1983 E-38 with the same problem. Knowing this upfront and expecting a sizable job I have researched this to great extent. I just Put her up on the hard two weeks ago to rebed the keel and rebuild the mast and rigging. I also will be attacking the cabin top rot issue. I also have rotten decks. I think I have come up with an ingenious solution. I haven't tried it yet but it is drilling holes and de coring it from the inside and then injecting structure expanding foam back in without opening up all the way. would love to talk more about it. I just finished my cabin sole.
    the cabin sole looks great! It would be awesome to come up with a technique to recore without removing one of the skins. There's a lot of people who'd be interested in seeing it work. I need to sit down and write it up, but I'm using a vacuum pump to install the new core. After a few test bags, I got the first piece of core up and it went really well. I'm planning on using 2 layers of 1708 to rebuild the bottom skin.