not sure if you are asking about the "hatch" or the deck. 
 
Assuming you have a cuddy. Earlier models had 2 plywood backed cushions covering the "porta-potty" compartment. Sounds like you had a one piece plywood cover there and that's what cracked? Or are you talking about the deck itself? 
 
I replaced the covers to the porta potty space and anchor space with 1/2 inch starboard. Rounded the edges with a router.
		 
		
		
		
		
		
		
			
		
		
		
		
		
	
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