Thread Check can add many custom features to our thread gages such as depth notches, blunt starts, blunt points or chamfers that are beneficial for several applications including thread depth gaging and short or shallow threads Blind Hole – A hole that goes partially through a part.   Blunt Point –The removal of a male center point from threads smaller than #6 (M4). This does not allow the gage to be face ground to within .5P. This is not a Blunt Start. See Convolution below.   Chamfer – An angle ground on the front of a gage that allows for easier assembly with the mating part   Convolution – Removal of the incomplete thread back to the first full thread. Also known as a “Blunt Start” or “Higbee Cut” per ASME B1.7 – 2006   Depth Notch – Measure from the centerline of the first full thread to the flat step of the notch. A depth notch is only used on a go plug gage and is used to measure thread depth.   Grind Face w/in .5P - A convoluted thread plugs face is ground back to the base of the first full thread. This permits the gage to inspect a blind hole to the bottom of the thread. https://www.threadcheck.com/technical-documents/Custom-Threads-Terms-and-Definitions.pdf Contact Thread Check Inc for more information [email protected] 800 767 7633 or 631 231 1515 www.threadcheck.com