Geoff, you don't say how you are using your gauge, vertically or horizontally. The picture is maybe not clear, but to be accurate the bar with the ball needs about a quarter inch extension of the bar past the ball. It appears the gauge "feeler" does not touch the ball while in repose. Of course that cannot be the case, but that how it appears. If your gauge was made as I described, and was used horizontally , you can get perfect readings every time.
Thanks for pointing that out - the photo is inaccurate...I'm not sure why they use it on their website.
When you set the gauge up, you drop the feeler to the ball and set the zero there.
