Wordsmith,

You are correct that shape is more important than composition. Any shape which reduces the amount of charge needed to ionize the air between the ground and a cloud is a lightning attractor. There are 2 main ways to do this - first, locally collect more charge; second, reduce the amount of air between the ground and the cloud. Fishing poles and golf clubs fall into the second category. When they are raised on high, they reduce the amount of insulating air between the cloud and the ground, thereby giving the electrical charge a locally easier path to follow. Material makes no difference in that case.

In your kayak, what makes you most susceptible to lightning is you sticking up above the water level. The coaming and coaming material are irrelevant. Your paddle is probably the greatest danger point because it typically rises above your head and because it comes to a sharp edge (which concentrates the charge). Your head, being round, has a reduced charge concentration. That's why flagpoles have round balls on top, to reduce the chance of lightning strikes.

Finally, carbon fiber is amazing stuff. It gets almost unbelievably stiff if all you're used to working with is glass. There are some differences between the way it handles, compared to glass. First, it doesn't wet out the same way. It doesn't absorb epoxy as readily as glass, nor does it turn transparent. You have to work a bit harder to make sure that the epoxy gets consolidated into the fiber. Next, whenyou cut it, little black threads go flying everywhere. Always wear a dust mask since there is an inhalation danger. Finally, epoxy-coated CF fibers are very sharp and brittle. If you don't handle it carefully, you could end up with invisible splinters in your hands.

Because CF is so brittle, you may want to cover it with a layer of 3 to 4 oz. glass to protect it.

Have fun, it's cool stuff.

Laszlo

My CF mastbuilding page

Soller Composites How-to pages

Thanks, Laszlo - I thought it was a bit of a red herring - and of course had quite overlooked the 'paddle in the air' point you make.  

I've read your blog on c-f mast making before - olive oil and all! - and will re-read it over the Easter break to glean some thoughts and no doubt tips and hints.   The Soller page was useful, too, and will also be re-read.   Much appreciated.

Happy Easter hols to all...

Wordsmith

There is an element of electrical danger with CF. Not to you but to your power tools! I wouldn't cut CF with any tools I cared about because the CF dust can easily short out your motors.