Drill Bit Sharpener for Grinder: Jigs and Freehand Truth

A bench grinder can put a working edge back on a dull bit three different ways. You can grind freehand, use a tool rest jig, or add an attachment. Skill decides which drill bit sharpener for grinder use actually works for you, not price.

Freehand sharpening costs nothing beyond wheel time. It takes practice to get both lips even, though. A jig or attachment trades some of that skill for setup time and a fixed way of holding the bit.

The right call comes down to wheel dressing, heat control, and equal lip length. Get those right and any of the three paths puts a sharp point back on a bit. Skip them and even the fanciest fixture will not save you.

What Actually Matters When You Sharpen Drill Bits On A Grinder

A dressed wheel is the starting point every method assumes. If the face is worn or out of round, no jig can put a true angle on a bit. The reference surface itself is already off.

Most general purpose bits use a 118 degree point angle. That splits into two 59 degree halves, with 8 to 12 degrees of lip clearance behind the edge. A simple check helps too: the chisel edge should sit at about 45 degrees to the cutting lips.

Both lips have to match in angle and length. Grind them unevenly and only one lip cuts. That drills an oversized hole and wears the bit fast.

High speed steel loses its temper the moment it turns blue at the tip. Light passes and frequent cooling keep that from happening. Grind past any blue color to restore a hard edge.

Freehand, Jig, Or Attachment: How Each One Grinds A Bit

Freehand On The Wheel

Freehand grinding is just you, the wheel, and practice. You roll the bit against the face by hand. You match angle and clearance by feel, then flip and repeat on the other lip.

Owner discussions on this method are consistent. Once the motion clicks, freehand becomes the fast default and jigs mostly gather dust. The same discussions also show a real learning curve, with beginners chewing up a few bits first.

This site covers the wrist roll and angle checks in the longer breakdown of this technique, worth reading before your first attempt.

Tool Rest Jigs

A tool rest jig clamps to the existing rest and holds the bit at a fixed angle. You feed the bit into the wheel by hand, but the jig sets the angle for you.

Owner reports on branded jigs are mixed at best. Several owners call them fiddly outside the exact bit size they were tuned for. One seller of these jigs even admitted the mechanism does not hold up well in practice.

The Attachment Tier

A drill bit grinding attachment mounts to the tool rest and holds the bit through a guided fixture. The angle stays fixed while you move the bit through the cut. The General Tools 825 is the common example here, rated for bits from 1/8 inch up to 3/4 inch, plus number and letter sizes.

The manufacturer lists an automatic adjustment to clearance angle. It also includes a reference table for matching point angle to material. That removes the freehand guesswork, though it still adds a fixture to set up and keep clean of grit.

Vs The Drill Doctor Path

This whole approach is not the only path, though. The Drill Doctor 750X is a dedicated machine built only for sharpening bits. It needs no wheel dressing and no freehand skill at all.

It clamps the bit, and a guided fixture does the motion for you. The manufacturer lists a 3/32 to 3/4 inch range and a point angle adjustable from 115 to 140 degrees. A split point feature stops itself before removing too much material.

How the Drill Doctor compares across its models covers the full lineup. If you would rather skip wheels entirely, that is the page to read next.

Mistakes That Ruin A Freshly Sharpened Edge

Skipping the wheel dress is the most common mistake. A glazed or out of round wheel cannot cut a true angle. It does not matter how careful your hand is.

Grinding past the blue heat line is another. Once the tip discolors, the temper is gone at that spot. The edge will dull again almost immediately.

Rushing the second lip is the third. Match the first lip’s angle and length exactly, or the bit will drill oversized and wobble.

Not every shop already owns the right equipment for this. If yours does not, the full lineup of drill bit sharpeners we cover lays out every other option side by side. For fixtures and shop gear beyond bits, everything else we cover on shop tools is a good next stop.

Frequently Asked Questions

What angle should I grind on a bench grinder?

Most general purpose bits use a 118 degree point split into two 59 degree halves. Lip clearance runs 8 to 12 degrees. A drill point gauge makes this easy to check.

Do I need a jig to sharpen drill bits on a grinder?

No. Freehand is the most common method among experienced shop owners, and our companion piece on manual bit sharpening covers the wrist roll and angle checks in full. A jig can shorten the learning curve for a beginner.

How do I know I overheated the bit?

Watch the tip color. Blue means the temper is gone at that spot, and you need to grind past it.

Is a drill bit grinding attachment worth the money?

For shops that already sharpen bits often, yes, it saves real time once it is set up correctly. For occasional use, freehand costs nothing and does the same job with practice.

What is the difference between an attachment and the Drill Doctor?

An attachment still uses your existing wheel and tool rest. The Drill Doctor is a standalone machine that needs no wheel, no dressing, and no freehand skill at all.

How often should I dress the wheel?

Dress it whenever the face looks glazed, uneven, or stops cutting cleanly. A true wheel face is what every sharpening method here depends on.