Outfitting the tandem kayak, Part 5: Bulkheads continued

Here is the bow bulkhead after I have laminated it in a layer of fiberglass.  The next step is to put the bulkheads in place, get them as "square"  (perpendicular to the boat's long axis) as possible, and start glassing them in place.  I start on one side of each bulkhead, attaching it to the inside of the boat with strips of fiberglass all the way around its edges.  Then I move to the other side and fill the gaps between the plywood and the inner surface of the boat with epoxy resin thickened with wood dust to the consistency of putty.  Finally, I lay strips of fiberglass around the edges of the bulkhead on that second side.






Here is the stern bulkhead after it has been glassed in on one side.  I will fill the biggest gaps, like the one visible at the bottom of the photo, with thickened epoxy from the other side.  Once that has hardened, I can do the fiberglass work on the other side.

This work involves positioning the boat one way, laying in some fiberglass and resin, letting it harden, and then positioning the boat another way.  This way, I have gravity working for me at all times.  Most of the time I'm able to work pretty comfortably, as in the photo at right, where I've got the boat suspended at such a height that I can stand up straight and work inside it.

However, there are a few moments when an uncomfortable working position can't be avoided.  The hardest place to reach is the aft side of the bow bulkhead, because the bulkhead has to be placed up beyond the bow paddler's foot pegs.  The photo at left shows me during what is probably the least pleasant part of this entire project.




At this point I should mention a property of epoxy resin that will be relevant throughout this project.  Resin takes several days to become fully cured.  After it has hardened but before it has fully cured, it is said to be "green."  When fresh resin is applied to green resin, the two resins will form a chemical bond.  But fully-cured resin will not bond chemically with fresh resin, and so it must be sanded so that a mechanical bond will be established between the new resin and the old.  (Remember when we used to patch bicycle tires as kids, and we had to scuff up the area around the leak so the patch would stick?)

The resin in the original boat is of course fully cured.  Therefore, I must sand the areas inside the boat where the bulkheads will be installed.  Meanwhile, once I start the installation job, I want to get it completed before any of the new resin has fully cured so I don't have to do any more sanding.