Ball attachment for surface gage for checking squareness

[Harvey Melvin Richards]

One way to check an item for square is to use a surface gage. You use the ball end of the vertical rod as your lower reference and an indicator as the upper reference and a known square surface as the datum. My problem with this method is that it makes the fine adjust on the surface gage difficult to use. So I took a hard drive magnet, a chunk of aluminum and a small tooling ball and came up with this.