Main hull frame

And what do we have here? A frame from the main hull, number 2 to be exact. We are moving right along aren’t we. You may notice the color of the fir plywood the frame is made from. A little information on this material is in order. 

This was a type of fir plywood made exclusively for the road sign industry in the Province of Alberta. Now Alberta is not a place any self respecting sailor would want to be caught in, especially in the winter. Because of –40 degree temperatures in the winters, wild wind and ice storms, + 100 degree temperatures in the summer coupled with dust and sand storms, the highway sign industry had to design a very strong and resilient material to make their signs from. 

One of the plywood mills took up the challenge and produced this material. It is called Crezone ply and is excellent for boat building. Crezone that is ½ inch thick is 5 ply, all equal thickness. You can not find ½ inch, 5-ply fir for sale in BC anymore. If you go to a specialty store, you might find some, imported from somewhere and at what cost? 

Crezone also has a layer of very porous Kraft paper applied to one side. I was very skeptical of this paper when I first saw it. I thought “What kind of bond am I going to get on that stuff?” I epoxied a few pieces of wood to a piece of the Crezone, a couple on the paper surface and a couple on the bare plywood surface on the other side. After a few days to cure, I tried to remove them. Not going to happen. All four pieces would not move. I took a hammer to them. The pieces on the bare plywood broke the first and second layer of ply away without breaking the glue line of epoxy between the wood piece and the plywood. The pieces on the front, on the Kraft paper, did the same. It was obvious that the Kraft paper was porous enough to allow the epoxy to flow through and attach to the wood behind. 

I found out later that the Kraft paper was the secret of how this plywood could maintain such a durable surface in all conditions. My main hull, wing decks, cabin top, etc. are made from this Crezone.