Cruisers Forum

Join CruisersForum Today

Thread Tools Rate Thread Display Modes
Old 14-01-2006, 06:51   #16
Senior Cruiser
Jeff H's Avatar

Cruisers Forum Supporter

Join Date: May 2003
Location: Annapolis, Maryland
Boat: Farr 11.6 (AKA Farr 38) Synergy
Posts: 543
Images: 13
I apologize for exerpting this from articles that I had written for other purposes but this thread contains two very important points of view that I strongly disagree with. The first has to do with the strength of older boats.

"One statement you see a lot is “Early boat builders did not know how strong fiberglass was and so made it very thick.” Horse Feathers! This is just plain bunk. The federal government had done a lot of research on Fiberglass during WWII and in the years following, and the information was widely available by the late 1950's and early 1960’s. As a kid, I had literature on fiberglass that pretty clearly analyzed its properties. Guys like Carl Alberg, who was working for the government designing fiberglass ammo boxes and other composite structures when he was hired by the Pearsons to design the Triton, knew exactly what fiberglass would do. They knew that the e-glass of that era was pretty poor quality and was especially prone to flexing and to fatigue. Designers of that era attempted to design fiberglass boats to be as stiff as wooden boats of the era. That took a lot of thickness since F.G. is very flexible compared to wood. This was especially true on a pound for pound basis.

They also knew that the fiberglass resins and cloths of that era were extremely fatigue prone, and so if the boats were not as stiff as wood, there would be major fatigue problems. This put early designers in a bind. If they made the glass boats as thick as a wooden planked hull they would be impossibly heavy. If they did not, fatigue would condemn them to a short life. They mostly chose to compromise. By that I mean they chose to do boats that were not as stiff as the wooden boats they replaced but were heavier. Early glass interpretations of wooden boats were generally heavier and carried less ballast than their wooden counterparts. They were much stronger in bending but not as stiff. As fatigue took place some of these early glass boats became even more flexible which leads to more fatigue, which can lead to a significant reduction in strength."

It is extremely wrong to say that the marine insurance industry does not know what it is talking about when they refuse to insure older boats. They see thousands of claims in any year and they are pretty vigillient in looking at trends and trying to understand why they are occurring. In the late 1990's the marine insurance industry noted that claims made on older boats seemed to be disproportionate to the source of the damage. (To quote from of my article again)

"In a study performed by the marine insurance industry looking at claims on older boats and doing destructive testing on actual portions of older hulls, it was found that many of these earlier boats have suffered a significant loss of ductility and impact resistance. This problem is especially prevalent in heavier uncored boats constructed even as late as the 1980's before internal structural framing systems became the norm. Boats built during the early years of boat building tended to use a lot more resin accelerators than are used today. They also would bulk up the matrix with resin rich laminations (approaching 50/50 ratios rather than the idea 30/70), and non-directional fabrics (mat or chopped glass) in order to achieve a desired hull thickness. Resin rich laminates and non-directional materials have been shown to reduce impact resistance and to increase the tendency towards fatigue. The absence of internal framing means that there is greater flexure in these older boats and that this flexure increases fatigue further. As a result of finding that a small collision will do disproportionate damage, there are an increasing number of marine insurance underwriters refusing to insure older boats."

Beyond all of that that these early laminates started out with less inherent strengths. While Insurance industry testing of older boats has shown that these heavy solid hulls did not have the strength of newer lighter hulls, the failure mode was not completely understood. As mentioned above, it was generally believed that the issues were inferior resins and fibers, poorer handling of the materials, poor resin ratios, and the extensive use of accelerators and fillers. What is learned in testing performed by the U.S. Naval Academy is that the problem may also lie in the extensive use of non-oriented fiber type laminates (mat). These old heavier so-called solid glass hulls actually used an enormous proportion of non-oriented materials which greatly reduce their impact resistance, stiffness, and tendency to resist fatigue.

So while these older boats may be less desirable because of their inferior sailing characteristics, they are also comparatively fragile when compared to better built, equally well maintained newer boats.


Jeff H is offline   Reply With Quote
Old 15-01-2006, 07:10   #17
Senior Cruiser
Talbot's Avatar

Cruisers Forum Supporter

Join Date: Jun 2004
Location: Brighton, UK
Boat: Privilege 37
Posts: 3,578
Images: 32
Whilst I admit to not having the expertise of some of our illustrious members, the concept that older boats are more susceptible to damage that newer ones is a load of crud. Somehwere in this forum is a link to a fibreglass expert showing damage to boats, and clear evidence that todays construction methods are considerably inferior in strength to the old fashioned slap a few more sheets of cloth and resin in to use it up system.
Point impacts that used to result in a little minor damage are now writing boats off, and delamination from cored construction is a major problem in accident damage, or even poor construction (see wildcat saga).

I am much happier having a 22 year old boat that is probably twice as heavy as modern construction, but 10x the ability to withstand any damage.

"Be wary of strong drink. It can make you shoot at tax collectors - and miss."
Robert A Heinlein
Talbot is offline   Reply With Quote
Old 15-01-2006, 08:08   #18
Registered User
capt lar's Avatar

Join Date: Feb 2005
Location: Cape Cod
Boat: currently "on the beach"
Posts: 729
Images: 12
I do not know which side is right on this issue. I think collision is not the main concern when talking about the life and value of a boat. It is a valid issue when talking about insurance and cost of repair, but it is the normal wear and tear thru loads, UV, salt, water intrusion (even thru epoxy) that add up over the years. If banks will not loan and insurance companies will not insure a boat, many will not buy so if you had a boat from, say, 1978 that was in good shape, do you think about selling just because of this age issue ? In another 5 years might she be viewed as a higher risk and therefor less marketable ? Is there a risk that the value might suddenly decrease based strictly on some insurer's or lender's chart ? The examples of Hinckley and Dyer do not give an answer because they are typically purchased and restored by folks with deep pockets paying cash. I do not think a 1958 Galaxy would get a loan, but since it is used for charter, I would think the owner has at least liability insurance, but possibly thru an umbrella on the business.
It is a vague area, but I have had some in those businesses tell me they "prefer" a boat to be under a certain age.


We have met the enemy and he is us. - Walt Kelly
capt lar is offline   Reply With Quote
Old 15-01-2006, 08:43   #19
Senior Cruiser

Cruisers Forum Supporter

Join Date: Feb 2003
Location: Macatawa Michigan
Boat: Amanda Faye 61' Custom Irwin aftcockpit ketch
Posts: 1,414
Images: 106
We talked to a loan broker about getting a loan for a 1955 Feadship and he said it would not be a problem. He said the only boats that were hard to get money for were wood and homemade. I know that it is important to be able to borrow money for a boat for maximum sale price.
irwinsailor is offline   Reply With Quote
Old 15-01-2006, 12:16   #20
Kai Nui

Posts: n/a
First, let me say that Jeff's knowledge of fiberglass far excedes mine. I am the first to admit this, howerver, often scientific facts do not take into consideration real world variables. How strong is stron enough? The strongest glass hull out there will likely be damaged running into a partially submerged container at 6 knots. Will a 1970 boat be damaged more than a 1990 boat? Maybe. The fact that I am trying to express is that the design is far more important than the age. A poorly built hull will fail before a well built hull regardless of age.
As for insurance company risk assessment, I still stand behind the statement that they are considering numbers without relating those numbers to real world circumstances. This goes back to the man in the lab telling the man on the boat how to trim the sails.
My opinion, and I admit that is what it is, is based on owning and sailing allot of boats. It is also based on repairs I have been involved with on a number of boats. A for instance: While I have repeatedly touted the quality of the Challengers, this is based on the modified full keel. This is a strong hull. And a thick one. On the other hand, I would not sail a fin keel Challenger, They are very weak right behind the keel, and where the strut is mounted. Without exception these areas have either been repaired, or need to be. I have seen numerous Catalina 30's of 70's vintage, that have been grounded, and poorly maintained, yet show no signs of hull problems.
THe statement that thick glass was a means of reducing flex, not a factor of the builders not knowing the strength of glass and over compensating may be true. I was not there. Over building is the common understanding, so I believe there must be some truth in it, even if it is not universally true.
All this said, I do agree that the ability to finance and insure a boat is ultimately the answer to the original question. Can you pay cash, and do you intend to resell the boat? If you can not pay cash, and hope to resell the boat in the next 5 years, I would certainly consider as new a boat as I could afford. To purchase a boat, that I intended to pay cash for, and insure minimally, and keep indefinitely, I would not rule out anything due to age.

  Reply With Quote

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 02:28.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.