(1) - Start by making a line for the 7/8” or 1-5/8” unistrut that you are using.

(2) - Lay the Smiddo on the line at the desired pipe size and make a dot for the center of the knock-out.

(3) - Use the 90º square to mark a vertical line on each dot.

(4) - Line up the flat edge of the Smiddo on the unistrut line with the proper pipe size on the line.  Mark a dot to indicate the center of the knock-out.

(5) - Now you are ready to begin drilling for each knock-out!