Cabin Deck Sag

[danpeace]

First of all, I have been spending months reading through old post trying to find the answer to my problem and I have not found anything specific enough. If anyone knows of a thread or discussion, please let me know.

Here is my problem. I bought a 1980 Hunter 33 a couple of years ago and have been restoring her. It has been loads of fun with scraped knuckles and drained bank accounts. I live in Minnesota and have a very short sailing season. This year my boat was put in two months earlier then normal (warm spring) and now in August I am faced with loosening stays. I have realized the deck plate between the mast step and the compression post is not doing its job and I will be spending the winter months repairing the problem. I have thought about injecting epoxy into the area, but I never have the sense it is completely repaired.

So, here is my question. I can't be the only one out there with this problem. What do others recommend as the fix? Do I cut a hole in the top of the deck and replace the wood, hoping I can make the repairs look like something other then a teenager with bondo, do I drill hundreds of holes, use epoxy and hope for the best, or is there a third option I have not thought of?

 

[Don S/V ILLusion]

What and how to fix the mast step sinking depends on the cause. First, are you sure the compression post didn't sink and that the base if it is structurally sound?

 

[danpeace]

What and how to fix the mast step sinking depends on the cause. First, are you sure the compression post didn't sink and that the base if it is structurally sound?

I am early sure it is above the compression post. The inside of the cabin has not sagged and there has been leaks from the vang mount into the cabin. When I look at the base of the post, it seems unchanged. But, as you know, that pressure can move around.

 

[KD3PC]

As Don says, you need to make sure where the fault lies.

IF you know where the wet is, and the area is small you can inject epoxy, but I would unstep and cut the top layer of glass and make sure that the coring and structure is as it should be....then repair and replace the top layer glass and fair in to the original cut line.

Less work in the long run, and you know what you have done and such.

Need to verify where the sink is..

 

[danpeace]

I will look closer at the bottom of the post. I took a small screw driver and probed around the base and felt no give. I had the harbor master give it a quick glance and he saw the sag in the cabin top. My hope in the next year or two to inject epoxy into the ribs and stringers (big projects I know) to ensure her longevity and seaworthiness. So, I plan to cover all possible problems. But, this is the first lash at the problem.

To cut a hole in the cabin deck or to inject epoxy - what would Cherubini do?

 

[Scott]

I am not at all familiar with your boat, but you say it's deck stepped. Before cutting into the deck, remove the trim down below and expose the probably wooden compression post. If it is anything like the h-31, it may be a "skeleton" of a piece of wood. Much easier than cutting the deck. When you have looked at the post, let us know. Many of us here have made the repair.

 

[Bob Pullen HC-33 1981]

Hi Dan
we just got through addressing the same issues you mention.
We had already comitted to taking the mast down, to inspect the deck around the cast aluminum "step"
We had noticed a crack in the headliner, just fwd of the comp. post (see pics)
We also noticed the compression post had also corroded at the base in the bilge
took off mast to change shrouds & rewire mast, so we also cut off a large patch of the deck skin around the cast aluminum base, lifted and inspected, found no evidence of rot, closed and re-glassed.
Inside we rebuilt the bilge support with new parts - see pix
super strong again, no cracks and solid as a could be
new shrouds from Sailing Services outta miami are totally sweet, and new wiring, antenna, single connection vhf wiring from antenna, etc...nice improvements

 

[sandpiper10471]

The guys are right. Either at the top or the bottom of the compression post. On my 79 H33, I could see the deck depressing below the mast. Mine turned out to be core rot. On your boat, you will have a bottom skin of glass, a layer of balsa (if memory serves 3/4"), a layer of glass, 1/4" plywood and a top skin of glass. Do the repair from above. You can use polyester or epoxy but don't use epoxy if using any chopped mat in your laminates. I would definitely not use the epoxy injection system favoured by JC. It doesn't get rid of water and this area must stand a great deal of compression which is balsa's finest attribute.

 

[danpeace]

Well, it has been a couple of months since I have check these replies and my 1980 Hunter 33 is safely sitting on her cradle ready for winter. Her mast is down and I have removed the mast step plate, checked for dry rot (which I have found) and have hired the harbor master to pressure inject epoxy into the cabin deck in the spring. But, that doesn't explain the crack on the port side of the compression post foot in the bilge that has suddenly disappeared. So, I looked further.

I have been enjoying my time, relaxing in the cushion free, cold cabin, exploring the cabin sole's lack of screws under the teak plugs (found empty space), when I turned my drill bits attention to the foot of the compression post. I have found that I am now the proud owner of compression post foot rot. Yes, I am now part of that exclusive club of Hunter owners whom wish skydiving was still an option as a life long hobby.

I have spent the morning rereading your posts (thank you, by the way, for your extensive knowledge and patience) and am realizing within the next few months I, too, will be able to post pictures of this completed project.

But, here is my question. From the photos Bob sent and from the absence of the crack on the port side of the post, can I assume the compression post foot is not structurally attached to the walls of the bilge or to the stringers? If the foot is removed, does the keel fall off or is it simply superficially attached to the bilge wall with fiberglass? I have a screw jack and I know how to use it, but I am reluctant to start cutting away at the foot in fear of creating a bigger problem.

Thanks....

 

[mauruuru]

I had a problem years ago with an O'day 30 because the through deck mast cutout had never been sealed and over the years the wood had gone spongy and rotted wherever the water leaked. First I dug out all the wood between deck and cabin top I could reach and filled it with epoxy. Next, I drilled a thousand holes in the deck ( a few hundred at a time) dug out the wood and filled the cavity with epoxy and then painted the deck. Worked great, strengthened the deck so no more sponginess and looked great when I was done painting.