The HDI is the only measuring tool that indicates the precise depth of hollow, edge balance, and rocker radius and transition points. This indication by the HDI will totally remove the skate grinding guesswork and deliver confidence to the skate sharpening professional and skater.
MEASURE FOR EVEN EDGES: Clamp the HDI onto the skate blade, push the gold bar (which controls the depth gauge) to one edge, and align the gauge to “0”. Now push the gold bar (depth gauge) to the other side to measure height of the other edge edge. Compare readings, and if the gauge reads “0” on both edges, your edges are even. If not, one edge will read higher (on the + side) or lower (on the – side) by x lines (thousands of an inch). This tells you exactly how far off you are and how to adjust to get to even.
MEASURE FOR RADIUS OF HOLLOW: First, measure the width of your skate blade and refer to the blade width chart given with your HDI. Now clamp the HDI onto the skate blade, and slowly push the gold bar (depth gauge) from one edge completely to the other. You will see the needle on the gauge drop down to x line. Take the lowest point the needle hits and refer to the blade width chart to calculate the radius of hollow.
MEASURE FOR PROFILE/ROCKER: Place the HDI on the center of your skate blade. Where the needle naturally reads on the gauge tells you your profile:
Needle at 3 o’clock position: 7 ft rocker (+/- 2 notches)
Needle at 12 o’clock position: 9 ft rocker (+/- 2 notches)
Needle at 9 o’clock position: 11 ft rocker (+/- 2 notches)
When you slide the HDI forward/backward on you blade at a certain point you will notice the readings jump greatly up/down. This is the transition point where your rocker ends on your blade.