"Mid Size Power Boats" - Buyers' Guide by David Pascoe

Sea Ray and Balsa Core Bottoms

The debate over the use of balsa cores in boat bottoms seems recently to have come to an end when, in October, 2002, Powerboat Reports ran a piece entitled "Core Complaints".  Purporting to be an editorial, when in fact the piece ran five pages and is a full-blown article, including a response from Sea Ray to a PBR inquiry for Sea Ray's response to allegations of serious problems with the use of balsa core in the bottom of their boats 40 to 55 feet built from 1995 to 2002 by;

(1) blaming some marine surveyors for "providing a lot of incorrect information during the process"

(2) claiming that balsa is widely used by many boat builders (without specifying where they use it)

(3) that balsa is "tried and tested [by Sea Ray]"

(4) that balsa core is "recognized, certified around the world [by] Lloyds Register of Shipping, Det Norske Veritas, Nippon Kaiji Kyokai, American Bureau of Shipping ...." and others.

Unfortunately, as respects item #4 above, the Sea Ray response fails to mention that those classification societies attach very strict rules to the use of balsa construction, standards that I'm certain that Sea Ray does not meet.  Because, if Sea Ray did meet those standards, they would surely have applied for certification from one or more of those societies.  Since they claim no such certification, we can be sure that they don't have it.  Meanwhile, two large yacht builders that do successfully use balsa on bottoms DO carry the ABS certification, and one Lloyds as well.  It costs a small fortune to attain those certs, which is why no production builder ever bothers.

Sea Ray goes on to say that, "if the source of water ingress is located and repaired in a timely manner, the balsa core will dry out and be fine." Un huh. And in response to recommendations of most marine surveyors that repairs be carried out by removing and replacing the wet and/or rotted balsa core, Sea Ray says that this procedure would likely cause more damage than its worth.  All of which sounds very much like an argument to do nothing short of finding a way to let a saturated hull naturally dry out.

Separately, Sea Ray issued a memorandum which includes a copy of a letter that I wrote to Baltec in 1996, in which I discussed the qualities of balsa as a core and found them superior to the foams that were being used at the time.  In 1996 Baltec's public relations reproduced the letter, copy of which Sea Ray attached and quoted from in the memorandum to all Sea Ray dealers and which has since had wide distribution beyond dealers.  Indeed, it is being used as a defense of balsa cored hull bottoms against Sea Ray owner complaints.

Once this was brought to my attention, it became clear to me that I made a mistake in that 1996 letter by not differentiating my views on the use of balsa in a boat's upper structures versus boat bottoms.

I will state for the record here that I have NEVER endorsed the use of balsa cores in boat bottoms, nor any other type of core materials.  Indeed, virtually all the core-related articles on this web site should make that painfully clear.  Nor can the writer of that Sea Ray memorandum claim that he is ignorant of my views on bottom coring.  That's because I had received a letter from him that indicated that Sea Ray personnel monitors our web site, as do most other builders.

In Sea Ray's defense it has become clear that the company has monitored our web site over the years and has taken note of complaints about certain issues that we have written about, and in ensuing years we have noted that more than a few of such complaints were remedied. Good for them and good for their customers.

I have no problem with giving credit where credit is due. However, I have long warned boat buyers about the dangers of balsa cores in boat bottoms going all the way back to 1966 when I first became aware of how catastrophic water intrusion into a cored bottom could be. I had hoped that Sea Ray would pick up on that one also, but, alas, they did not until it came back and bit them hard on the backside. In fact, both balsa and foam cored bottom failures were a well-known problem throughout the 1960's and 1970's, so much so that I ridiculed Sea Ray for adopting a practice that resulted in horrific problems over the course of two preceding decades, debacles from which most everyone in the boat building industry learned a lesson - some the hard way, others by observance of other's mistakes. Everyone, that is, except the good folks at Sea Ray. Then, as I hear it, Cruisers, Inc., and others jumped on the band wagon and started putting balsa in their boat bottoms.

Frankly, I couldn't believe that "designers" at such large corporations could be so ignorant until I discovered just what kind of people were designing boats at Sea Ray and the others. No more degreed naval architects but industrial engineers and CAD operators with little or no marine experience. Does that mean that no highly experienced naval architect would ever use a balsa core in a boat bottom? It does not because I can name several that do. Huckins and Cresent Yachts, both builders of large multi-million dollar yachts have used balsa cores on bottoms, and have done so successfully.

Yet there is an important caveat to this point: Balsa can be successfully used as a core, but only with extreme care in design and application. The extreme care that can only come from the minds of the highly experienced. Moreover, successful design and use of balsa as a bottom core is not cheap; it adds greatly to the cost of design and construction. But production boat builders do not use cores to improve strength but to reduce the cost of the amount of fiberglass used because balsa is cheaper than solid FRP.

And even though a real expert can create a reliable balsa cored hull, I still think that this is a terrible idea because if the hull becomes damaged and water intrusion does occur, the damage is extraordinarily costly, and sometimes even impossible to repair. But to use the material in a high production operation is plain nuts when there is so much emphasis on reducing labor costs. Great skill and low wages are contradictory factors. For example, I surveyed one brand new, never titled model 550 in which there were two holes drilled through the inside skin near the keel line, a feature that would drain water directly into the core. How did those holes get there? Obvious some worker at Sea Ray had to have drilled them for reasons one can only guess at.

But the point is clear: Even if designed and constructed perfectly, there is still plenty of room for the unanticipated event happening to wreck the boat through no fault of the owner. When we compare the potential risks of a cored bottom with a solid glass bottom, the former makes about as much sense as trying to fly an aircraft with only half a wing, or going to sea without communications.

Myself and many other surveyors have been involved with numerous failed bottom cores of Sea Rays and can testify that Sea Ray's use of balsa in their hulls is highly flawed, and often lacks even common sense in its application and design. Though Sea Ray claims thirty years of successful use of balsa in upper structures, there isn't an experienced surveyor around who couldn't list endless examples of rotten deck cores in Sea Rays. Not only deck cores, but Sea Ray can't even get the use of plywood in hull stringers right, as this web site has repeatedly documented. There are uncountable numbers of older Sea Rays (10+ years) out there with rotting plywood stringers, a problem that few other boat builders who use the material have had.

This disaster that Sea Ray has created is not getting the publicity it deserves for a variety of reasons. One is, as Powerboat Reports indicates, that Sea Ray, in settling lawsuits, is obtaining non disclosure agreements in the terms of settlement, a common practice by corporate lawyers in product liability cases. Naturally, Sea Ray is doing all it can to keep it quiet. Another stems from the attitudes of the troubled boat owners. When you've got a huge sum of money tied up in a defective product, you don't want to advertise that fact. If the owner fails to get a satisfactory settlement, he's going to want to sell the boat to some other unsuspecting buyer so that he can recover some of his money. When the defect becomes common knowledge, the value of the boat will plummet.

There's just one small problem with that: It is illegal to knowingly sell a defective product to someone. It's called fraud.

So it ends up that marine surveyors are caught in the line of fire between boat owners and the builders. On the one hand the builders want to discredit the surveyors and/or shut them up. On the other, boat buyers want to avoid buying into the problem, but should they end up with a problem, they want to silence the surveyors as well. Both sides shoot the messenger!

Sea Ray was in trouble long before this debacle because their since replaced management thought that boom times would last forever, and expanded production capacity to keep up with the economic bubble (a management error that is predictable as the changing of the seasons and which has brought down numerous boat builders). Now Sea Ray has hundreds, perhaps thousands of ticking time bombs (balsa cored boat bottoms) out there waiting to explode. Will Sea Ray survive the mistake? Only time will tell, but meantime I wouldn't make any bets on Brunswick stock.

Related Reading:
Cored Hull Bottoms: The Final Word - Posted July 12, 2001
Core Materials: The Hamburger Helper of Boat Building, Reviewed in the Light of History - Posted October 31, 1998

Posted November 20, 2002

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David Pascoe - Biography

David Pascoe is a second generation marine surveyor in his family who began his surveying career at age 16 as an apprentice in 1965 as the era of wooden boats was drawing to a close.

Certified by the National Association of Marine Surveyors in 1972, he has conducted over 5,000 pre purchase surveys in addition to having conducted hundreds of boating accident investigations, including fires, sinkings, hull failures and machinery failure analysis.

Over forty years of knowledge and experience are brought to bear in following books. David Pascoe is the author of:

In addition to readers in the United States, boaters and boat industry professionals worldwide from nearly 80 countries have purchased David Pascoe's books, since introduction of his first book in 2001.

In 2012, David Pascoe has retired from marine surveying business at age 65.

On November 23rd, 2018, David Pascoe has passed away at age 71.

Biography - Long version

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Mid Size Power Boats Mid Size Power Boats
A Guide for Discriminating Buyers
Focuses exclusively cruiser class generally 30-55 feet
With discussions on the pros and cons of each type: Expresses, trawlers, motor yachts, multi purpose types, sportfishermen and sedan cruisers.
Buyers' Guide to Outboard Boats
Selecting and Evaluating New and Used Boats
Dedicated for offshore outboard boats
A hard and realistic look at the marine market place and delves into issues of boat quality and durability that most other marine writers are unwilling to touch.
Surveying Fiberglass Powewr Boats
Surveying Fiberglass Power Boats
2nd Edition
The Art of Pre-Purchase Survey The very first of its kind, this book provides the essentials that every novice needs to know, as well as a wealth of esoteric details.
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Last reviewed September 25, 2016.