If you follow my directions for building a boat, you will end up with a boat. If you follow some directions for testing whether your kayak is safe you will still end up with a boat that can kill you.

I would suggest an easy test if I knew of one that was meaningful. Just because someone can tell you how to build a boat does not mean there is an easy and useful way of testing some other object which will tell you much useful stuff about the boat itself.

I could tell you to stand on the deck of your finished boat and jump up and down slightly. It should be able to handle it. If the boat breaks, you didn't build it strong enough. If the boat survives, it might be strong enough to survive your use.

I am not worried about my liability, I just don't want to tell you that breaking something other than your boat will tell you anything about your boat which you can have any real confidence in. I'm not trying to be coy, snotty, or obtuse. I just can't think of any reasonable, practical test which would tell you what you want to know.

Maybe I lack the imagination to come up with such a test. If you think you have one, let us know.

I can come up with more sophisticated tests to determine relative properties, such as is a given panel as strong or weaker than some standard, but this doesn't tell you if the standard would meet your requirements. These test don't answer the question "Is the boat strong enough" except indirectly by saying "Boat X was built using technique A, my panel N is stronger than a panel M which was also built using technique A. I built my boat Y using the same techniques as panel N. Boat X did what I want to do and N is stronger than M, and M is similar to X, therefore Y should be able handle as much as X." Fairly involved reasoning.

This is what you could learn from a standardized 3-point or impact test. This technique is fairly common practice, although still allows for big mistakes. The scatter in the Gougeon Brothers data shows some of the problems involved.

I don't mind the idea of describing tests similar of what Gougeon Brothers did, but I don't think this is what you want (I may be wrong). You seem to want something that you can do with a few simple tools and get a quick answer as to whether your fiberglass/epoxy job is strong enough. I can't think of any such test that you can trust. I am open to suggestions.

: You're already far out on a limb when it comes to liability by describing how
: to build the boat and recommending materials and selling that. This you
: do. You also describe building methods and do give testing advice. From
: grading and selecting wood for strips, to how to glue them together
: properly and the laying on of glass. If all you said was "buy some
: stuff and build a boat with it" you couldn't sell your kits or your
: book.

: A basic explanation of how to evaluate a rip test, or another test if you
: prefer, would not suddenly place you in a new liability position. Nor
: would you be saying "this boat is built correctly" based on this
: test. You would simply be giving people a method by which to see if
: they've done some glassing right. You're already half way there by
: describing failure to properly saturate the cloth, floating the glass on
: excess epoxy, and warning about outgassing. A rip test is simply another
: way to determine floating fiberglass and such without damaging the boat
: itself, or even involving the boat.

: As far as the notion of being foolproof, your book is about a subject that is
: absolutely not foolproof. Mistakes are easy to make, and are very common.
: Building a kayak is not foolproof. That's why you put the liability
: disclaimers in your literature that you do.

: To say that giving a builder of your boats a method for determining if they
: are "good or bad" at laying fiberglass is irresponsible of you
: is absurd on the face of it. Irresponsibility on your part would be
: preventing a builder from being able to determine if their boat has been
: built in a "good or bad" manner. I really don't think you meant
: to say it this way, but I'm not quite sure what you are trying to say, or
: avoid.