Builders' Forum Archives
Re: shearwater glass ques
Posted by LeeG on Jan 27, 2008
4oz is adequate from the standpoint of paddling in rough conditions but when there's actual impact against 4mm plywood as will occur on the bottom of the hull 4oz will dent too easily. So two layers makes sense for the average 175lb paddler bobbing on a shore with a few rocks underneath. That's why 6oz glass has been the standard for kits, it simplifies construction to one piece and weight of cloth. With 8oz of glass on the bottom exterior you're already a bit 'over' the average construction.
Regarding the compartments. My feeling is that there should be glass on the bottom panels at least in the aft compartment for a couple feet and in the forward compartment for one foot. The space six inches behind the aft bulkhead will be more vulnerable to cracking stresses than where your feet are located in the glassed cockpit simply from the regular practice of getting in/out of your kayak by sitting on the aft edge of the coaming. When you're sitting there the kayak will settle down until it rests on something. My sense is that if a paddlers weight is being pressed onto a panel of 4mm plywood there should be glass on both sides. As you get further to the ends the bottom panels get narrower and present a sliding surface to any rocks so it's less critical than the widest portion of the bottom panel where all your weight is located. When you're in the kayak it's under your butt, when you're sitting on the aft edge of the coaming that weight is spread behind you and in front of you. Doesn't quite make sense that 6" behind the bulkhead there's no glass and 6" forward there is glass.
In Response to: Re: shearwater glass ques by David S. on Jan 27, 2008