Major work on the hull-deck joint

[Crazer]

The one major flaw with old, full keel Pearsons is the joint between the hull and the deck. This is a well documented area of weakness, and in the case of one Triton, resulted in the boat being damaged beyond economic repair and the subsequent abandonment of the voyage. The problem is that Pearsons were built by people who did not know anything about boats, and one of the things they consistently did wrong was to join the hull and deck assemblies with epoxy along the joint and then a  thin layer of fiberglass tabbing on the inside. On my boat, I discovered, the total thickness of the hull at the joint, including the tabbing, is about 3/8 of an inch, in some places maybe half an inch at most. This is obviously insufficient if the boat were to get hit by a wave broadside or if other large forces were applied to the joint. After doing some thinking, I came up with what I think is a workable solution. My thought is to glass over the hull from the outside, starting about 9 inches down from the toe rail, glassing over the toe rail and onto the deck another 9 inches. The planned thickness of the new exterior tabbing would be about 3/8" at the joint and over the toe rail. I would also reinforce the interior tabbing, bringing it up to 1/4" or more. I've attached a diagram of what I am thinking. Does this seem like a good solution and one that would be sufficient for offshore work?

[CharlieJ]

Well,that would surely work, but before I did all that, I'd get in touch with James Baldwin and see what his thoughts are. He did after all, take his Triton Atom around the world twice.

http://www.atomvoyages.com/

Here's a link to his details of what he has done to her over the years-

http://www.atomvoyages.com/atom.html

[Crazer]

Thanks, it didn't occur to me to give James a shout, but that's a very sound idea. To be clear, my boat is a Pearson Wanderer, although I did give the impression it was a Triton. For all intents and purposes there construction is the same.

[Cruiser2B]

I believe I saw the pictures of the Triton that was knock down on a passage and caved in entire side of boat, scary. Since then I have been giving some thought to the same thing although my boat is an Alberg 30. My thought process was to add an few layers of fiberglass cloth to the existing joint then add larger fasteners and backing plates to the hull-deck joint entire way around the boat and finally add some structure knees on the underside of the decks.  These knees would be place from underside of deck to the hull. I thought about thru-bolting them through the deck...maybe overkill... I am not sure if the Alberg 30 would have the same issue but better safe than sorry as I am sure my Alberg was not built with the intention of crossing oceans :)

An interesting thing I heard the other day was that the hull to deck joint on the hans christian 36 "Rebel Heart" started to give way after a storm in the pacific. The boat had been knock down 3-4 times during the storm and they said they were leaking 60-70 gallons a day. As many of you know the boat was ultimately scuttled and crew saved. But that failure coupled with an infant with ailing health led to them deciding to abandon ship. Eye Opening stuff.

[Crazer]

Yes, that story about the damage to Rebel Heart only gave me more reason to focus on improving my own boat. I have had a couple of other ideas that involve through bolting things. These might be more feasible in terms of cost and time. I also had someone point out that adding so much fiberglass would create a stiff area on a flexing hull, which could cause it's own problems. The ultimate solution may take some time to develop.

[Captain Smollett]

my boat is an Alberg 30. My thought process was to add an few layers of fiberglass cloth to the existing joint then add larger fasteners and backing plates to the hull-deck joint entire way around the boat and finally add some structure knees on the underside of the decks.  These knees would be place from underside of deck to the hull.

The A-30 hull-to-deck joint is already through bolted...or sort of.  It's essentially riveted. I think there's a difference between the pre-liner and liner boats in the details of how it's all put together, but it's my understanding that both are strong.

I know of at least one fairly well known A-30 owner that drilled out all the rivets and replaced them with through-bolts.

To me, this is a bit overkill, and here's why I think this.  The cap rail (the wooden rail along the hull to deck joint) *IS* through bolted already.  AND. the genoa track is ALSO through bolted for the length of its run.

That's not to say don't do it; but, chances are, the hull to deck joint on an A-30 is already pretty solid.  Point is, the hull to deck joint on an Alberg 30 is not just 'tabbed in.'

Also, there are already knees along the underside of the deck for support where the shrouds attach.  You probably already know this and are talking about adding additional ones.  But, this is one area where it IS advised to "upgrade" in that the chainplate bolts are undersized and need to me drilled out and larger bolts installed.

In fact, this is what led to Yves' dismasting in the Southern Ocean.  He drilled and installed oversize bolts for all but the lowers, and it was a lower shroud chainplate bolt that sheared off, allowed the mast to pump in the seas he was in and caused the mast to fail...at the lower spreaders (he had converted to a multi-spreader rig).  It left enough mast standing for him to rig a jury sail to sail back to the Chatham Islands for repairs.

It is from his experience that the conventional thinking among A-30 owners is that any boat to be taken offshore or raced hard should have ALL chainplate bolts upped in size.

I thought about thru-bolting them through the deck...maybe overkill... I am not sure if the Alberg 30 would have the same issue but better safe than sorry as I am sure my Alberg was not built with the intention of crossing oceans :)

Many Alberg 30's have crossed oceans and quite a few have circumnavigated, including around the Stormy Capes.

There are things on the boat to have concern about (mast support beam, for example, if it's a pre-liner boat), but I don't think the hull to deck joint is one of them. 

Don't borrow trouble, as the saying goes...

[Cruiser2B]

Cpt Smollett,

I am sure you maybe correct that somethings are probably fine the way they are. You are very knowledgeable on the Alberg 30, I often look here for answers to questions about my boat. The reason I have concern on my hull to deck joint is while searching the Alberg30.org mailing list archives I found where my boat back in the 90's had an issue with this joint. I simply typed in my hull #457 in search function and it came back where one of the previous owners had what he described as "oil Canning" basically what I gather was the deck was lifting from the joint up on port side bow....seems as if the rivet and adhesive had failed....I guess my boat was built on a Friday :-\.......After looking at my boat I can see where the boat had an issue. It looks like it was repaired with some sort of sealant like 5200. I cannot be certain so I will address it during my upcoming refit. While I agree that Alberg 30 are stout seaworthy boats mistakes were made in building, not every layup is identical and obviously errors were made.

Also thought it might be worth a mention that most of, if not all, the rivets used on them are aluminum and when I redid my standing rigging and chainplates in 2012 I found most of them to be very corroded and almost without effort pull apart from the joint it held together on the mast(spreaders), boom and interior, yes the shelf in my boat was riveted to the tabs. So at this point my boat is 43 yrs old and I believe every rivet, nut and bolt will have to gone over.

I might also mention that I did replace my 1/4 machine screw and chainplates during the mast refit. The chainplates are now 1 1/2 x.250 316L polished stainless and bolts were upgraded to 7/16" 304 Stainless. All hardware, including nearly 200 rivets were purchased from a local hardware supplier that sells only mil-spec product(not chinese 304 stainless from Fastenal). This hardware cost me a pretty penny but worth every cent for piece of mind for next 40yrs. Another Alberg 30 owner one day stopped by the yard where I was doing the rivets on my boom and I told him about the failures in mine and one other I read on a blog....so we walked over to his boat 1970 #449 and sure enough his gooseneck was only attached by 1 rivet.....all others had corroded and head had snapped off. I reriveted his gooseneck for him...5 or 6 rivets and some tef-gel and he should be good to go now for quite awhile. Anyway, my point is,  even the areas of the Alberg 30 that aren't know for trouble may start to have issues after 40-50 years of service, and for piece of mind I will redo everything I feel needs attention...overkill maybe but piece of mind......after all our boats were not built to sail offshore ;)

[Cruiser2B]

Also, there are already knees along the underside of the deck for support where the shrouds attach.  You probably already know this and are talking about adding additional ones.  But, this is one area where it IS advised to "upgrade" in that the chainplate bolts are undersized and need to me drilled out and larger bolts installed.

In fact, this is what led to Yves' dismasting in the Southern Ocean.  He drilled and installed oversize bolts for all but the lowers, and it was a lower shroud chainplate bolt that sheared off, allowed the mast to pump in the seas he was in and caused the mast to fail...at the lower spreaders (he had converted to a multi-spreader rig).  It left enough mast standing for him to rig a jury sail to sail back to the Chatham Islands for repairs.

It is from his experience that the conventional thinking among A-30 owners is that any boat to be taken offshore or raced hard should have ALL chainplate bolts upped in size.

The problem with these knees(chainplate attachment points for lowers) is that in factory form they are not tabbed or connected to the deck in anyway, so they provide zero lateral support of hull to deck joint. I have tabbed mine to the deck and will complete the reinforcement of these knees during the refit as I will tie them into the shelving as well

[Chris]

Probably well known here already is Hal Roth's reinforcement of the hull to deck joint of he and his wife Margret's Spencer, WHISPER where he removed all of the screws holding the joint together and then glassed it over. He reported in Two Against The Horn this stopped all the leaking from the original joint and greatly strengthened the hull-to-deck joint.

Badger's (1963 Columbia 24) joint is formed by nesting the deck with it's upturned lip inside of the hull's indented lip glassing them together from beneath inside the cabin. It was then covered with a teak combing which was screwed through the joined lips of hull and deck. Once Badgers rotten teak combing is stripped I will run filleting at the base of the lip and the hull indent and then lay up two layers of cloth three inches into the deck and three inches down the side of the hull.

I was told by a well respected board maker that I might want to cut the cloth for this job into largish oval patches and overlap them rather than try to wrestle with "tape" of the cloth. He felt that there wouldn't be any loss of strength and the job would be easier and faster. Hmmm I dunno. Will have to play with that idea.
I'm glad that Columbia made the reinforcement job so easy!

[Jim_ME]

I would be inclined to do all of the reinforcement to the interior of the joint, if possible. In those older unlined boats, the fiberglass is right there to grind and bond to. Outside you would have to grind off the gelcoat on the upper hull and deck.

If the hull was pushed in by the force of the seas, I would be inclined to add stiffeners to the hull interior. One way to do this is to take foam strips and lay up laminate over them to create stiffeners, both ribs and longitudinal members. Some do this to create a stringer to fasten wooden ceiling strips over them. I think that Charlie did this on Tehani. It provides an attractive traditional finish to the hull, say in the V-berth area, and exposed hull in the main cabin, quarter berth areas. With enough strips, and reinforcement laminate stiffeners, no doubt it would have some strengthening effect, too.

I believe that it would be more effective to stiffen the hull a bit so that it cannot buckle inward and avoiding any strain on the hull deck connection, rather than trying to brace the hull by beefing up the joint. 

If I was determined to add some reinforcement to the exterior, I think that I would remove the wood toe rail, reinforce the joint and then reattach the toe- rail over it. Again, if I possibly could, I would do all the reinforcement at the interior. You could also add gussets that are glassed to the hull and underside of the deck. I just saw some photos of this somewhere in my browsing recently. You could reinforce the joint and then install a foam fillet and glass over that to stiffen and bond the deck to the hull farther out from the inside corner, and that would add strength.

I'm quite tired and haven't read all of the posts below carefully, so may have suggested something that was already proposed.

Another thing in favor of a small boat is that the hull is smaller (especially traditional designs with lower freeboard) than a much larger boat, so there is less surface area exposed to the forces of the waves.

[Chris]

Hey Jim!
I agree with the stringer/ceiling strip idea and that is my plan for Badger. You are so right about the look and strengthening! The first edition of THIS OLD BOAT the author gives a good step-by-step for installing these. I am looking forward to setting cork panels behing the ceilings as well so as to insulate the hull, eliminate sweating and mildew while moderating temperatures in the cabin.
While I am usually all to happy to "overbuild" (I mean that in the best way), I think that since the interior tape seems healthy I am pretty confident about reinforcing from the top side .   Have to admit that the biggest reason for this solution is that I am just too happy to avoid any inside taping upside down! The other positive aspect appeals to my  laziness ... No more varnishing!!!! Just a few coats of Pro-Line white wrapped over the combing from the deck and onto the hull just where the glassing ends.

[Cruiser2B]

Started looking at my hull to deck joint today. I knew there was an issue from posts I had read on Alberg30.org public list....I found evidence of a repair...or what I though was a repair

here is what I found:

http://svsalacia.blogspot.com/2015/08/alberg-30-refit-hull-to-deck-joint.html

[Cruiser2B]

http://svsalacia.blogspot.com/2015/08/alberg-30-refit-hull-to-deck-joint_19.html

A few more photos of the failed area. I took these after removing some of the sealant...