> A flexible bulkhead would be the least obtrusive but one is always left
> with the problem of sealing around the keelson, the chines and the
> gunwhales.

Sorry my first post was a little flip so here's more complete ideas

Flexible Bulkheads:

I know just about zilch about these kayaks, but here goes. I assume the stringers, gunwale, and keelson are immediately adjacent to the skin. I assume no floorplanking at the bulkhead location, ribs w/ 6" between, and easy access - say just behind the seat.

After the skin is on, (but before painting?), take a 10oz pc of ballistic nylon and draw the section profile on it. Cut the cloth out 5" beyond beyond this profile. Push into place and baste it w/ nylon cord at the first profile line with the excess 5" flapping toward you. It's now approximately in place and is as structural as the basting stitching - add more if you wish. Under the flap and all around the yak, liberally smear out our old standby sealant and baste the flap around the yak so that the sealant compresses out all around. You now have a 5" wide region of seal that can go up and around the stringeres etc. The sealant will bridge the sharp corners and the 5" allows slop.

So now you have a bulkhead that is as strong as the skin and basting - say 4" wide around the whole profile. And it is sealed fairly well too. Obviously a front hatch is harder to access, but the process would be the same.

Bulkheads:

By now you all know I hate raised hatches, and the VCP hatch in my opinion only belongs on garbage containers. And a skin kayak where the lines of the skeleton are really expressed is especially aborted when these guys are used. So the inclination to use a zippered hatch is born from this - or a hatch that somehow conforms to the lines of the skin yak:

So what would happen if you cut a hole in the skin of the kayak before it is stretched and hemmed in a ring of 5/8" diam nylon rope around the profile. Then the skin is stretched and painted. The hole now conforms to the lines of the kayak but has a slight raised perimeter b/c of the rope. The rope tension ring will transfer the skin forces. 5" outside this perimeter and all around sew in small webbing loops say at 6" spacing. Cut a pc of skin 3" wider than the profile and sew in webbing loops directly opposite the loops in the deck (or you could alternate). Spread saran wrap over the hole and lace up the 'hatch'. Paint the hatch. After dry, you know what I'll say next - take it off, and on the underside, smear on our old friend silicone sealant. Tie it back on and let set up. When dry, remove the hatch, peel off the saran wrap and now you have:

- A very low profile hatch that doesn't interfere with the lines of your kayak

- An attatchment system (laces or ropes - you could use a zipper and the idea is ok but the character is all wrong) that complements the whole construction approach. It'll sorta look like dwg 7B of the "fitting reprise" post.

- And I think it may be fairly structural too!

Thoughts?

-mike