About the M1 Caliber category

The M1 Caliber Measuring Tool accurately measures any flat material slid underneath it.

I keep having a small problem with my m1 i did the calibration like it was told on the instructions and watched the YouTube video but the way the m1 measure now is to the other side of the blade where i want to cut or will be off by an 1/8th of an inch at times did i do something wrong in the calibration.