Model ship gratings come in a range of sizes. modelers central is the home of wooden model boat builders. order online for fast delivery.. Your profile doesn't give any indication of where you are.....but here in the us you can buy the grating sections in the major boat stores like boatus.. The ship's grating shown here is slightly less than one inch (2.54 cm) on a side. it was scratch built with the aid of the device shown below. this is the first wooden boat model that this modeller has built. the kit is by midwest and the model is 1:14 scale or 7/8" to the foot... mare nostrum work in progress..
If the grating is to be, say, 1" slats with 1" clear spaces, then make the edge pieces 1