Center drill question

You can make your own spotting drills for free. You can re-point a broken drill to the angle you want for spotting regardless of helix angle. You can thin the web and use a 2-angle grind or other little tricks to get the result you want. Since chip removal isn't a problem, I just grind D-bits in a conical profile with a good clearance cut past the cutting edge. They can also be ground to match fastener heads and run as a countersink. If the subject interests you, read Harold Hall's tool grinding book that is included in our site's free library. He does more to explain drills in four pages than you'll find in some of the big references.
 
Be reminded drills do not commence with material removal, with common web variety as the most obvious, split points the quickest. They extrude metal for the leading edge of flute to engage. Being fluteless, spotters offer high rigidity, yet the points can be fragile. A center drill does a good start, when followed by a correctly ground bit, by initiating a cut immediately.
I usually penetrate a bit deeper than one diameter of the center drill point, deeper yet to accommodate larger bits. In very small drills, a center drill barely more than a punch mark is sufficient.
 
Get a good, sharp and hard center punch.

Your transfer punch will make a good starting point.

A good center punch with proper hold and good smack will make a good starting point for your drill.

Center drill work well as they are designed to hit a moving target and cut properly.

For using a drill press everything is going to move, your drill rod in chuck as a guide will help.

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