hi,i have fence gate that i want to put a radius on at the top,but am not sure how tofigure out how to do it.
the gate is 47inchesx47inches,there is 12.5inhces above the top board.
when iput a screw in the middle of center board
i get an inch too wide on each side i believe
there is system do radius,s but right now it slips my mind,i do not want to cut boards until i get it closer,thank,s

You should be using two nails same height but a few inches apart from themselves. Then use a string tied as a circle. Let the string fall over the two nails and as you trace the circle the string will get shorter as it goes towards the ends of the gate and longer towards the middle.

thank,s for the info,but i wanted to get it done so what i did was take a piece of house wire and used like you do for laying out how to
do work on a lawn and bent in shape that i wanted for the arch then scribed a line on board
to the shape needed cut with saw then used grinder to fihish off shape,thank,s