Pics of deck construction / cross section - was a million little holes

[tjspiel]

The jib tracks arrived from James Steele today, - whose P-18 was crushed under 12 ft of snow.

One of the tracks was still attached to a section of the cabin top that he cut out. It's pretty interesting:

You cannot view this attachment.

That's the top view. Here's one side that shows the foam core and what looks like vertical "ribs" every inch or so. I think that's some sort of epoxy in the last few inches near the edge. The other end is like that too.

You cannot view this attachment.

Here's the other side that shows the plywood core:

 You cannot view this attachment.

The fasteners for the jib track are right on the very edge of the plywood. After I remove the track from that slice of deck I'll cut through one of the bolt holes to see if they were filled in any way.

Attaching these to my boat is most likely going to be an October or maybe even April task. Before I do that I'm going to contact Bill to see if the older boats like mine had plywood in that area. If so, I'd want make sure I've got the tracks positioned over the plywood. Like I said, this one is very close to being over the foam core. 

[Riggerdood]

Interesting slice of info there Tom. I wonder if, when tapped, the foam cored areas make a different sound than the plywood cored areas do? Prolly not doable on the narrow strip you have, but Bill might suggest that as a way of telling where the boundary is on your boat, if it is cored the same way.

[DBthal]

Good photos.  It's a rare opportunity to really see a cross section of the laminate and core.

The hardware looks as good as new.

[Dave Scobie]

Plywood core is a rot disaster waiting to happen.  Much worse and fast failure than balsa if water gets in.  Overdrill the holes and fill with thickened epoxy then drill the correct hole size for the fastener.

What size backing washer was used?  I'd use fender washers.

[tjspiel]

Plywood core is a rot disaster waiting to happen.  Much worse and fast failure than balsa if water gets in.  Overdrill the holes and fill with thickened epoxy then drill the correct hole size for the fastener.

What size backing washer was used?  I'd use fender washers.

They are fender washers. Folks have already given me useful tips on how to clear out some materiel between the fiberglass layers to make room for epoxy. Think I'm going to go the dremel route. It's one of my favorite tools.

Will need 12 holes per track so it's going to be a bit of work.

[Krusen]

I suspect that a common stud finder will easily tell where the plywood is.  Run the finder across every foot or closer, marking each side, to establish a reliable line for each edge.

That is an interesting sandwich, gives a clear education on the construction.

Krusen

[tjspiel]

I suspect that a common stud finder will easily tell where the plywood is.  Run the finder across every foot or closer, marking each side, to establish a reliable line for each edge.

That is an interesting sandwich, gives a clear education on the construction.

Krusen

A stud finder is an excellent idea, - thanks !

[Brian S]

The "ribs" of resin are because foam core looks much like the 1" ceramic tile you put down in a bathroom. They are attached on the underside but have channels between each square, and resin fills in those areas when it's laid out.