The Arcing Layout - Basic Types of Bowling Ball Layouts The Arcing layout - This layout is what I call the 90 degree layout, or Ebonite's 90 degree layout. It is used on most house shots. It's also used if the bowler wants to play the bowling lane at the track area, or between the 13 and 8 board at the arrows. This layout has the widest range of usefulness. I recommend it for 90% of house shots and for bowlers that only bowl on a house shot. In other words, for the once or twice a week average bowler. See my article How To Start A Basic Arsenal Of Bowling Balls. It explains this layout and the surface to match the lane conditions. The layout - When the ball is drilled put the pin 4.5 inches from your positive axis point (pap) or under your ring finger. On a symmetrical ball the center of gravity (cg) should be in line with the pin angling toward your thumb. On an asymmetrical ball the mass bias should be in line with the pin and directly underneath your thumb. This is Ebonite's 90% layout. Refer to the Recommended Resourses section below for more valuable bowling information.