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Re: Some questions take a long time to answer
By:Rehd
Date: 10/30/1999, 8:17 pm

> Water has two important properties relative to shores. Water is softer and
> water is a liquid. In general, the same forces on the boat will cause less
> damage on the water than near shore. If you can get into the boat and away
> from the shore, you should have no problems.

> If you get in and out of your boat in 6" of water, you will probably
> never cause any damage. If you get in and out of your boat in 3" or
> less of water, you will eventually put your hull between a rock (your
> foot) and a hard place (a rock on the bottom).

> Will this cause any damage? It depends on what your hull layup is designed
> for. If the layup is designed for use on a sandy bottomed small lakes, you
> may have damage. If the layup is designed for use on rocky bottomed shores
> in large surf conditions, you may not have problems.

> How can you tell? You could do a test. Something like setting a steel ball
> on the hull and applying a load. If you know what size of ball and what
> size of load, you could do a small test panel (or even test the hull on a
> finished boat) and determine if the layup was suitable.

> I don't know what size of ball or what load to use. I did try today. I set
> a 3"x6" test panel on the ground (outside up), set a 7/16"
> steel ball bearing on the panel, set a board on the ball (for balancing),
> and stepped on the board.

> All of the E-Glass (up to 16oz), S-Glass/graphite, and graphite/Kevlar
> layups had the same failure - the epoxy failed leaving bare fibers and a
> path for water into the wood. It is fair to say the more glass the better.
> (Graphite is never any good.)

> The 4.8oz satin Kevlar produced indented wood but the epoxy and Kevlar
> were sound. If you like Kevlar on the exterior of the boat, ...

> Clearly, the ball diameter was too small for the load to give a reasonable
> performance prediction under the load used. A 6" diameter ball (local
> rock size) might be a more useful size with the load being your weight.

Thank You George. That answered a lot of my question. Originally, my concern was that there are folks talking about using thinner materials and lighter construction. If he/she does this and have good success, but, only weigh in at 125 to 160 lbs., then I see their post and decide to do the same, at 250 lbs, I'm not gonna have equally successful results. ??? Both of us hitting the same rock will cause a signifigant? difference in results. You're in affect, multiplying the force being applied to the rock. Bound to make a difference!! Thanks again for the (late, but, none the less, usefull) answers. I appreciate your effort.

Rehd

Messages In This Thread

Re: Some questions take a long time to answer
Rehd -- 10/30/1999, 8:17 pm