I had start of 5.5m Sea Kayak project on last month.

I need to find Apart Kayak bulkhead information in my sea kayak project stage. My bulkhead marine plywood thickness is 8mm with bulkhead centre plywood is 4mm with extra 330-csm fibreglass for save weight?

What is size of plywood round with filler on bulkhead? (say radial round 2"?)

A 5.5m Sea Kayak stitches & tape plywood design by David Payne is born in Canada and living in Sydney but I wanted sea apart kayak built for storway and lived in housing commission tenant

I put 8mm plywood apart bulkhead in my 5.5m Sea Kayak Stitch-and-Glue design (non-apart kayak) by Australian David Payne also Apart Bulkhead of Sea Kayak Stitch-and-Glue design by Gerry Gladwin at Volkskayaks webpage.

I am not sure apart bulkhead weight is apart bulkhead laminate two of 4mm Plywood thicknesses and total 8mm plus fibreglass CSM laminate total 10mm said by Gerry Gladwin less my Apart bulkhead weight question-no answer.

I had check with apart bulkhead plywood 8mm and centre plywood 4mm with 330gsm cover and 6 S/S 1/4" or 6.5mm Bolt & nut weight total 1.720grams on after 1.900gram in apart bulkhead project stage without 6 S/S 1/4" or 6.5mm Bolt & nut.

Can you tell to me for more apart bulkhead information pleade.