Grinding a large drill bit - GIF

[Altair]

Grinding a large drill bit.




Previously:

Drill bit sharpening jig - video
Drill bit sharpener - video
Circular saw blade sharpening machine - GIF

[Floradawg]

I grind mine from the leading (cutting) edge. I guess you grind that one how ever you can hold it.

[Skun Knuckles]

That doesn’t look right on so many levels.

[Toolmaker51]

I grind mine from the leading (cutting) edge. I guess you grind that one how ever you can hold it.

Yeah. On a disk sander. Very straight cutting edge, control of included angle, and limited heat.
So where is the grinding gauge, unless he is just removing bad material prior true grinding. I won't envision the load on machine or part from unbalanced cutter profile.

[NortonDommi]

Like Skun Knuckles,(love your handle mate!), I thought that doesn't look right then I realised he is probably 'dubbing' the angles to put more pressure on the central part of the cutting edge.
I hand sharpen using a variety of methods while I'm still capable and have found that the method demonstrated here:

at Tom's Techniques is very quick and does a great job on the majority of sizes I use. It is also one of the easiest to teach someone else how to sharpen a bit and have success.

I like to use Secondary Point Angles,(SPA),on anything above say 1/4"/6 mm as described on page 2 of this excellent article from Newman Tools. It certainly makes a difference in bit use before a resharpen.
Drill_Point_Geometry_nt.pdf

[Floradawg]

Great job of explaining the proper technique. I usually roll the drill to attempt to replicate a factory shape but it is probably easier and a better result obtained your way. I will use your method next time I need to hand sharpen a twist drill.

[tooly]

I don't think I could lift that drill let alone grind it. Defiantly prefer core drills.