Diva Without Bulkheads?

[MikeY]

Hola,

Looking to build a kayak from plans. I've built two others previously, a Pygmy Arctic Tern 17 with bulkhead and hatches, and an Arctic Tern 14 with no bulkheads/hatches. Love'em! I take them out directly through the surf to play in the ocean.

I've decided that I prefer no hatches and bulkheads. I built the hatched kayak first, and have taken in water in "heavy waves and high seas" in the ocean. Although I think I've solved the leak problem, to be safe I use float bags in both fore and aft compartments. If water gets in, I have no way to pump it out.

The second boat has float bags shoved into the bow and stern. The bags also serve as dry bags, so I'm comfortable with taking trips and not having hatches. The second boat is *much* lighter, and not just due to reduced size. At the low weights of these boats, a few pounds means significant percentage reductions in weight.

So has anyone built a diva without the bulkheads, using possibly internal ribs instead? I assume the bulkheads provide structural integrity and stiffness too, along with providing the shape for the deck to form over.

Thoughts?

[Brent]

I haven't built the Diva, but have built three canoe/kayaks of similiar size. The bulkheads are very important for stiffness. I think you may find internal ribs are not a substitute for bulkheads, especially with the type of boating you describe. BUT, the bulkhead do not have to be watertight! Consider leaving a 1 inch gap at the top and bottom of the bulkhead to let water flow in/out. Some of the boats I have built have rigid flotation foam behind this type of free draining bulk head. I took care to insure that water would not be trapped behind the bulkhead - eventually leading to rot. The boats are unsinkable.

[ricardo]

What Brent said about the bulkheads.

But I think the main problem is you can't get the compound curves that make that deck so nicely shaped without the hatch openings.

My hatches only leaks a drop. Or two. Three. Four. Five... 8)

[MikeY]

What Brent said about the bulkheads.

But I think the main problem is you can't get the compound curves that make that deck so nicely shaped without the hatch openings.

My hatches only leaks a drop. Or two. Three. Four. Five... 8)

Hmmm, haven't seen plans yet. Are the hatches cut out after construction of the top, or are they built in, so to speak?

On my ATs, you cut the hatch out (or not) after the kayak is close to complete. The hatch itself is constructed of the cutout. So that's my knowledge base for kayak hatches to date.

[capt jake]

My kayak hatches are water tight. I used this method or making a channel/seal, it worked out pretty slick!

http://oneoceankayaks.com/Wshophtm/Shop20.htm

[Designer]

Mike,

As Ricado said, the deck has compound curves and we use the forward hatch and the cockpit cutout to merge one curve into another. On the aft deck this is not an issue, because there is no compound curvature. Also around the cockpit where it merges into the aft deck with some compund curve is not an issue, because you will still have a cockpit cutout.

I can't see how you can blend the raised deck at the forward end of the cockpit without the fore hatch cutout into the forward deck. In doing this you would be changing the deck crown line(deck centerline). Pygmy and CLC use methods that require mutiple chines or inverted V's for the deck to try to get a similar shape.